Merged revisions 638786-638802,638805-638811,638813-638814,638816-639230,639233-639241,639243-639253,639255-639486,639488-639601,639603-639835,639837-639917,639919-640056,640058-640710,640712-641156,641158-641184,641186-641795,641797-641798,641800-641933,641935-641963,641965-641966,641968-641995,641997-642230,642232-642562,642564-642565,642568-642570,642572-642573,642576-642736,642739-642877,642879,642881-642890,642892-642903,642905-642945,642947-643624,643626-643653,643655-643669,643671,643673-643830,643832-643833,643835-644342,644344-644472,644474-644508,644510-645347,645349-645351,645353-645559,645561-645565,645568-645951,645953-646193,646195-646311,646313-646404,646406-646665,646667-646853,646855-646869,646871-647151,647153-647185,647187-647277,647279-647566,647568-647573,647575,647578-647711,647714-647737,647739-647823,647825-648155,648157-648202,648204-648273,648275,648277-648302,648304-648333,648335-648588,648590-648622,648625-648673,648675-649141,649144,649146-649556,649558-649795,649799,649801-649910,649912-649913,649915-650128,650131-650132,650134-650137,650140-650914,650916-651991,651993-652284,652286-652287,652289,652291,652293-652297,652299-652328,652330-652425,652427-652445,652447-652560,652562-652933,652935,652937-652993,652995-653116,653118-653124,653126-653483,653487-653519,653522-653550,653552-653607,653609-653667,653669-653674,653676-653814,653817-653830,653832-653891,653893-653944,653946-654055,654057-654355,654357-654365,654367-654648,654651-655215,655217-655277,655279-655281,655283-655911,655913-656212,656214,656216-656251,656253-656698,656700-656756,656758-656892,656894-657135,657137-657165,657168-657179,657181-657354,657356-657357,657359-657701,657703-657874,657876-658032,658034-658284,658286,658288-658301,658303-658307,658309-658321,658323-658335,658337-658348,658351,658353-658832,658834-658983,658985,658987-659066,659068-659402,659404-659428,659430-659451,659453-659454,659456-659461,659463-659477,659479-659524,659526-659571,659574,659576-660255,660257-660262,660264-660279,660281-660343,660345-660473,660475-660827,660829-660833,660835-660888,660890-663321,663323-663435,663437-663764,663766-663854,663856-664219,664221-664489,664494-664514,664516-668013,668015-668142,668144-668152,668154,668156-668256,668258,668260-669139,669141-669455,669457-669657,669659-669808,669810-670189,670191-671321,671323-672229,672231-672549,672551-672552,672554-672561,672563-672566,672568,672571-673049,673051-673852,673854-673862,673864-673986,673988-673996,673998-674347,674349-674890,674892-674910,674912-674936,674938-674952,674954-675078,675080-675085,675087-675217,675219-675660,675662-675670,675672-675716,675718-675726,675728-675733,675735-675775,675777-675782,675784,675786-675791,675794-675852,675854-676200,676202,676204,676206-676220,676222-676309,676311-676456,676458-676994,676996-677027,677030-677040,677042-677056,677058-677375,677377-677968,677970-677971,677973,677975-677994,677996-678286,678288-678538,678540-680393,680395-680469,680471-680529,680531-680852,680854-681529,681531-681571,681573-682224,682226,682228,682231-682281,682283-682335,682337-682507,682509,682512-682517,682519-682532,682534-682619,682622-682777,682779-682998,683000-683019,683021-683022,683024-683080,683082-683092,683094-683095,683097-683127,683129-683131,683133-683166,683168-683698,683700-683705,683707-683757,683759-683787,683789-683870,683872-683879,683881-683900,683902-684066,684068-684074,684076-684222,684224-684254,684257-684281,684283-684286,684288-684292,684294-684298,684300-684301,684303-684308,684310-684317,684320,684323-684335,684337-684348,684350-684354,684356-684361,684363-684369,684371-684453,684455-684883,684885-684937,684940-684958,684960-684970,684972-684985,684987-685053,685055-685063,685065-685259,685261-685262,685264-685266,685268-685282,685285-686035,686037-686045,686047-686052,686054-686206,686208-686215,686217-686277,686279-686289,686291-686620,686622-686623,686626-686627,686629-686639,686641-686843,686845-686976,686978-687402,687404-687422,687424-687428,687430-687442,687444-688425,688427-688641,688643-688649,688651-688654,688656-688824,688826-688909,688911-689543,689545-689558,689560-689635,689637-689703,689705-689715,689717-689718,689720,689722-689972,689974-690090,690092-690093,690095-690111,690113-690258,690260-690261,690263-690403,690405-690410,690412-690460,690462-690516,690518-690533,690535,690537-690625,690627-690635,690637-690720,690722-690725,690727-690728,690730-691382 via svnmerge from

https://svn.apache.org/repos/asf/poi/trunk

........
  r690739 | nick | 2008-08-31 18:24:10 +0100 (Sun, 31 Aug 2008) | 1 line
  
  HPBF docs update
........
  r690761 | josh | 2008-08-31 20:08:36 +0100 (Sun, 31 Aug 2008) | 1 line
  
  removed AreaEval.getValues (initial work for bug 45358)
........
  r690772 | josh | 2008-08-31 20:44:11 +0100 (Sun, 31 Aug 2008) | 1 line
  
  Partial fix for bug 45358 - parsing area refs with rows above 32767
........
  r690825 | josh | 2008-09-01 00:59:26 +0100 (Mon, 01 Sep 2008) | 1 line
  
  Improving AreaI interface and AreaPtg hierarchy
........
  r690835 | josh | 2008-09-01 02:48:45 +0100 (Mon, 01 Sep 2008) | 1 line
  
  Converted AreEval and RefEval to be lazy (part of fix for bug 45358)
........
  r690836 | josh | 2008-09-01 03:26:33 +0100 (Mon, 01 Sep 2008) | 1 line
  
  Fixed IF() to handle different types for the first arg
........
  r690837 | josh | 2008-09-01 03:34:05 +0100 (Mon, 01 Sep 2008) | 1 line
  
  Update status for bug 45358 (fixed with r690772, r690835 and r690836)
........
  r691017 | nick | 2008-09-01 17:51:09 +0100 (Mon, 01 Sep 2008) | 1 line
  
  DV related fixes from Pierre Lavignotte
........
  r691180 | yegor | 2008-09-02 10:59:53 +0100 (Tue, 02 Sep 2008) | 1 line
  
  improved handling of StyleTextPropAtom bit masks, added more read-write roundtrip tests
........
  r691182 | yegor | 2008-09-02 11:03:11 +0100 (Tue, 02 Sep 2008) | 1 line
  
  continue making progress with hslf hyperlinks
........


git-svn-id: https://svn.apache.org/repos/asf/poi/branches/ooxml@692907 13f79535-47bb-0310-9956-ffa450edef68

37 files changed, 1210 insertions, 1611 deletions

diff --git a/src/java/org/apache/poi/hssf/record/NameRecord.java b/src/java/org/apache/poi/hssf/record/NameRecord.java
index 6c6c53a92b..71f3bf6fb7 100644
--- a/src/java/org/apache/poi/hssf/record/NameRecord.java
+++ b/src/java/org/apache/poi/hssf/record/NameRecord.java
@@ -27,8 +27,8 @@ import org.apache.poi.hssf.record.formula.Ptg;
 import org.apache.poi.hssf.record.formula.Ref3DPtg;
 import org.apache.poi.hssf.record.formula.UnionPtg;
 import org.apache.poi.hssf.usermodel.HSSFWorkbook;
-import org.apache.poi.hssf.util.AreaReference;
 import org.apache.poi.hssf.util.RangeAddress;
+import org.apache.poi.ss.util.AreaReference;
 import org.apache.poi.util.HexDump;
 import org.apache.poi.util.LittleEndian;
 import org.apache.poi.util.StringUtil;
@@ -626,7 +626,7 @@ public final class NameRecord extends Record {
 	}
 
 	private Ptg createNewPtg(){
-		Ptg ptg = new Area3DPtg();
+		Ptg ptg = new Area3DPtg("A1", 0); // TODO - change to not be partially initialised
 		field_13_name_definition.push(ptg);
 
 		return ptg;
@@ -673,9 +673,7 @@ public final class NameRecord extends Record {
 
 			// Add the area reference(s) 
 			for(int i=0; i<refs.length; i++) {
-				ptg = new Area3DPtg();
-				((Area3DPtg) ptg).setExternSheetIndex(externSheetIndex);
-				((Area3DPtg) ptg).setArea(refs[i].formatAsString());
+				ptg = new Area3DPtg(refs[i].formatAsString(), externSheetIndex);
 				field_13_name_definition.push(ptg);
 				this.setDefinitionTextLength( (short)(getDefinitionLength() + ptg.getSize()) );
 			}
diff --git a/src/java/org/apache/poi/hssf/record/formula/Area2DPtgBase.java b/src/java/org/apache/poi/hssf/record/formula/Area2DPtgBase.java
new file mode 100644
index 0000000000..2193854f47
--- /dev/null
+++ b/src/java/org/apache/poi/hssf/record/formula/Area2DPtgBase.java
@@ -0,0 +1,59 @@
+/* ====================================================================

+   Licensed to the Apache Software Foundation (ASF) under one or more

+   contributor license agreements.  See the NOTICE file distributed with

+   this work for additional information regarding copyright ownership.

+   The ASF licenses this file to You under the Apache License, Version 2.0

+   (the "License"); you may not use this file except in compliance with

+   the License.  You may obtain a copy of the License at

+

+       http://www.apache.org/licenses/LICENSE-2.0

+

+   Unless required by applicable law or agreed to in writing, software

+   distributed under the License is distributed on an "AS IS" BASIS,

+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

+   See the License for the specific language governing permissions and

+   limitations under the License.

+==================================================================== */

+

+package org.apache.poi.hssf.record.formula;

+

+import org.apache.poi.hssf.record.RecordInputStream;

+import org.apache.poi.hssf.usermodel.HSSFWorkbook;

+import org.apache.poi.util.LittleEndian;

+

+/**

+ * Common superclass of 2-D area refs 

+ */

+public abstract class Area2DPtgBase extends AreaPtgBase {

+	private final static int  SIZE = 9;

+

+	protected Area2DPtgBase(int firstRow, int lastRow, int firstColumn, int lastColumn, boolean firstRowRelative, boolean lastRowRelative, boolean firstColRelative, boolean lastColRelative) {

+		super(firstRow, lastRow, firstColumn, lastColumn, firstRowRelative, lastRowRelative, firstColRelative, lastColRelative);

+	}

+	protected Area2DPtgBase(RecordInputStream in) {

+		readCoordinates(in);

+	}

+	protected abstract byte getSid();

+

+	public final void writeBytes(byte [] array, int offset) {

+		LittleEndian.putByte(array, offset+0, getSid() + getPtgClass());

+		writeCoordinates(array, offset+1);       

+	}

+	public Area2DPtgBase(String arearef) {

+    	super(arearef);

+	}

+	public final int getSize() {

+		return SIZE;

+	}

+	public final String toFormulaString(HSSFWorkbook book) {

+    	return formatReferenceAsString();

+	}

+    public final String toString() {

+        StringBuffer sb = new StringBuffer();

+        sb.append(getClass().getName());

+        sb.append(" [");

+        sb.append(formatReferenceAsString());

+        sb.append("]");

+        return sb.toString();

+    }

+}

diff --git a/src/java/org/apache/poi/hssf/record/formula/Area3DPtg.java b/src/java/org/apache/poi/hssf/record/formula/Area3DPtg.java
index 3c9404ac39..ba207ab5c6 100644
--- a/src/java/org/apache/poi/hssf/record/formula/Area3DPtg.java
+++ b/src/java/org/apache/poi/hssf/record/formula/Area3DPtg.java
@@ -18,11 +18,9 @@
 package org.apache.poi.hssf.record.formula;
 
 import org.apache.poi.ss.usermodel.Workbook;
-import org.apache.poi.ss.util.CellReference;
-import org.apache.poi.hssf.util.AreaReference;
 import org.apache.poi.hssf.record.RecordInputStream;
-import org.apache.poi.util.BitField;
-import org.apache.poi.util.BitFieldFactory;
+import org.apache.poi.ss.util.AreaReference;
+import org.apache.poi.ss.util.CellReference;
 import org.apache.poi.util.LittleEndian;
 
 /**
@@ -34,238 +32,63 @@ import org.apache.poi.util.LittleEndian;
  * @author Jason Height (jheight at chariot dot net dot au)
  * @version 1.0-pre
  */
-public final class Area3DPtg extends OperandPtg implements AreaI {
+public final class Area3DPtg extends AreaPtgBase {
 	public final static byte sid = 0x3b;
 	private final static int SIZE = 11; // 10 + 1 for Ptg
 	
-	private static final BitField rowRelative = BitFieldFactory.getInstance(0x8000);
-	private static final BitField colRelative = BitFieldFactory.getInstance(0x4000);
-	
-	private short field_1_index_extern_sheet;
-	private int field_2_first_row;
-	private int field_3_last_row;
-	private int field_4_first_column;
-	private int field_5_last_column;
+	private int field_1_index_extern_sheet;
 
 
-	/** Creates new AreaPtg */
-	public Area3DPtg()
-	{
-	}
-
-	public Area3DPtg( String arearef, short externIdx )
-	{
-		setArea(arearef);
+	public Area3DPtg( String arearef, int externIdx ) {
+		super(arearef);
 		setExternSheetIndex( externIdx );
-
 	}
 
-	public Area3DPtg(RecordInputStream in)
-	{
+	public Area3DPtg(RecordInputStream in) {
 		field_1_index_extern_sheet = in.readShort();
-		field_2_first_row = in.readUShort();
-		field_3_last_row = in.readUShort();
-		field_4_first_column = in.readUShort();
-		field_5_last_column = in.readUShort();
+		readCoordinates(in);
 	}
 
-	public Area3DPtg(short firstRow, short lastRow, short firstColumn, short lastColumn,
+	public Area3DPtg(int firstRow, int lastRow, int firstColumn, int lastColumn,
 			boolean firstRowRelative, boolean lastRowRelative, boolean firstColRelative, boolean lastColRelative,
-			short externalSheetIndex) {
-		  setFirstRow(firstRow);
-		  setLastRow(lastRow);
-		  setFirstColumn(firstColumn);
-		  setLastColumn(lastColumn);
-		  setFirstRowRelative(firstRowRelative);
-		  setLastRowRelative(lastRowRelative);
-		  setFirstColRelative(firstColRelative);
-		  setLastColRelative(lastColRelative);
-		  setExternSheetIndex(externalSheetIndex);
+			int externalSheetIndex) {
+		super(firstRow, lastRow, firstColumn, lastColumn, firstRowRelative, lastRowRelative, firstColRelative, lastColRelative);
+		setExternSheetIndex(externalSheetIndex);
 	}
 
 	public String toString() {
 		StringBuffer sb = new StringBuffer();
 		sb.append(getClass().getName());
-		sb.append(" [");
 		sb.append("sheetIx=").append(getExternSheetIndex());
 		sb.append(" ! ");
-		sb.append(AreaReference.formatAsString(this));
+		sb.append(formatReferenceAsString());
 		sb.append("]");
 		return sb.toString();
 	}
 
-	public void writeBytes( byte[] array, int offset )
-	{
-		array[0 + offset] = (byte) ( sid + getPtgClass() );
-		LittleEndian.putShort( array, 1 + offset, getExternSheetIndex() );
-		LittleEndian.putShort( array, 3 + offset, (short)getFirstRow() );
-		LittleEndian.putShort( array, 5 + offset, (short)getLastRow() );
-		LittleEndian.putShort( array, 7 + offset, (short)getFirstColumnRaw() );
-		LittleEndian.putShort( array, 9 + offset, (short)getLastColumnRaw() );
+	public void writeBytes(byte[] array, int offset) {
+		LittleEndian.putByte(array, offset + 0, sid + getPtgClass());
+		LittleEndian.putUShort(array, 1 + offset, field_1_index_extern_sheet);
+		writeCoordinates(array, offset+3);
 	}
 
-	public int getSize()
-	{
+	public int getSize() {
 		return SIZE;
 	}
 
-	public short getExternSheetIndex()
-	{
-		return field_1_index_extern_sheet;
+	public short getExternSheetIndex() {
+		return (short)field_1_index_extern_sheet;
 	}
 
-	public void setExternSheetIndex( short index )
-	{
+	public void setExternSheetIndex(int index) {
 		field_1_index_extern_sheet = index;
 	}
 
-	public int getFirstRow()
-	{
-		return field_2_first_row;
-	}
-
-	public void setFirstRow( int row )
-	{
-		field_2_first_row = row;
-	}
-
-	public int getLastRow()
-	{
-		return field_3_last_row;
-	}
-
-	public void setLastRow( int row )
-	{
-		field_3_last_row = row;
-	}
-
-	public int getFirstColumn()
-	{
-		return field_4_first_column & 0xFF;
-	}
-
-	public int getFirstColumnRaw()
-	{
-		return field_4_first_column;
-	}
-
-	public boolean isFirstRowRelative()
-	{
-		return rowRelative.isSet( field_4_first_column );
-	}
-
-	public boolean isFirstColRelative()
-	{
-		return colRelative.isSet( field_4_first_column );
-	}
-
-	public void setFirstColumn( short column )
-	{
-		field_4_first_column &= 0xFF00;
-		field_4_first_column |= column & 0xFF;
-	}
-
-	public void setFirstColumnRaw( short column )
-	{
-		field_4_first_column = column;
-	}
-
-	public int getLastColumn()
-	{
-		return field_5_last_column & 0xFF;
-	}
-
-	public int getLastColumnRaw()
-	{
-		return field_5_last_column;
-	}
-
-	public boolean isLastRowRelative()
-	{
-		return rowRelative.isSet( field_5_last_column );
-	}
-
-	public boolean isLastColRelative()
-	{
-		return colRelative.isSet( field_5_last_column );
-	}
-
-	public void setLastColumn( short column )
-	{
-		field_5_last_column &= 0xFF00;
-		field_5_last_column |= column & 0xFF;
-	}
-
-	public void setLastColumnRaw( short column )
-	{
-		field_5_last_column = column;
-	}
-
-	/**
-	 * sets the first row to relative or not
-	 * @param rel FIXME: Document this!
-	 */
-	public void setFirstRowRelative( boolean rel )
-	{
-		field_4_first_column = rowRelative.setBoolean( field_4_first_column, rel );
-	}
-
-	/**
-	 * set whether the first column is relative
-	 */
-	public void setFirstColRelative( boolean rel )
-	{
-		field_4_first_column = colRelative.setBoolean( field_4_first_column, rel );
-	}
-
-	/**
-	 * set whether the last row is relative or not
-	 * @param rel FIXME: Document this!
-	 */
-	public void setLastRowRelative( boolean rel )
-	{
-		field_5_last_column = rowRelative.setBoolean( field_5_last_column, rel );
-	}
-
-	/**
-	 * set whether the last column should be relative or not
-	 */
-	public void setLastColRelative( boolean rel )
-	{
-		field_5_last_column = colRelative.setBoolean( field_5_last_column, rel );
-	}
-
-
-	/*public String getArea(){
-		RangeAddress ra = new RangeAddress( getFirstColumn(),getFirstRow() + 1, getLastColumn(), getLastRow() + 1);
-		String result = ra.getAddress();
-
-		return result;
-	}*/
-
-	public void setArea( String ref )
-	{
-		AreaReference ar = new AreaReference( ref );
-		
-		CellReference frstCell = ar.getFirstCell();
-		CellReference lastCell = ar.getLastCell();
-
-		setFirstRow(	(short) frstCell.getRow() );
-		setFirstColumn(	(short) frstCell.getCol() );
-		setLastRow(     (short) lastCell.getRow() );
-		setLastColumn(  (short) lastCell.getCol() );
-		setFirstColRelative( !frstCell.isColAbsolute() );
-		setLastColRelative(  !lastCell.isColAbsolute() );
-		setFirstRowRelative( !frstCell.isRowAbsolute() );
-		setLastRowRelative(  !lastCell.isRowAbsolute() );
-	}
-
 	/**
 	 * @return text representation of this area reference that can be used in text
 	 *  formulas. The sheet name will get properly delimited if required.
 	 */
-	public String toFormulaString(Workbook book)
-	{
+	public String toFormulaString(Workbook book) {
 		// First do the sheet name
 		StringBuffer retval = new StringBuffer();
 		String sheetName = Ref3DPtg.getSheetName(book, field_1_index_extern_sheet);
@@ -282,29 +105,8 @@ public final class Area3DPtg extends OperandPtg implements AreaI {
 		}
 		
 		// Now the normal area bit
-		retval.append(AreaReference.formatAsString(this));
+		retval.append(formatReferenceAsString());
 		
-		// All done
 		return retval.toString();
 	}
-
-	public byte getDefaultOperandClass() {
-		return Ptg.CLASS_REF;
-	}
-	// TODO - one junit relies on this. remove
-	public boolean equals( Object o )
-	{
-		if ( this == o ) return true;
-		if ( !( o instanceof Area3DPtg ) ) return false;
-
-		final Area3DPtg area3DPtg = (Area3DPtg) o;
-
-		if ( field_1_index_extern_sheet != area3DPtg.field_1_index_extern_sheet ) return false;
-		if ( field_2_first_row != area3DPtg.field_2_first_row ) return false;
-		if ( field_3_last_row != area3DPtg.field_3_last_row ) return false;
-		if ( field_4_first_column != area3DPtg.field_4_first_column ) return false;
-		if ( field_5_last_column != area3DPtg.field_5_last_column ) return false;
-
-		return true;
-	}
 }
diff --git a/src/java/org/apache/poi/hssf/record/formula/AreaI.java b/src/java/org/apache/poi/hssf/record/formula/AreaI.java
index 5a0a21e861..477d32f677 100644
--- a/src/java/org/apache/poi/hssf/record/formula/AreaI.java
+++ b/src/java/org/apache/poi/hssf/record/formula/AreaI.java
@@ -14,47 +14,63 @@
    See the License for the specific language governing permissions and
    limitations under the License.
 ==================================================================== */
+
 package org.apache.poi.hssf.record.formula;
 
 /**
- * Common interface for AreaPtg and Area3DPtg, and their
- *  child classes.
+ * Common interface for AreaPtg and Area3DPtg, and their child classes.
  */
 public interface AreaI {
-    /**
-     * @return the first row in the area
-     */
-    public int getFirstRow();
-
-    /**
-     * @return last row in the range (x2 in x1,y1-x2,y2)
-     */
-    public int getLastRow();
-    
-    /**
-     * @return the first column number in the area.
-     */
-    public int getFirstColumn();
-    
-    /**
-     * @return lastcolumn in the area
-     */
-    public int getLastColumn();
-    
-    /**
-     * @return isrelative first column to relative or not
-     */
-    public boolean isFirstColRelative();
-    /**
-     * @return lastcol relative or not
-     */
-    public boolean isLastColRelative();
-    /**
-     * @return whether or not the first row is a relative reference or not.
-     */
-    public boolean isFirstRowRelative();
-    /**
-     * @return last row relative or not
-     */
-    public boolean isLastRowRelative();
+	/**
+	 * @return the first row in the area
+	 */
+	public int getFirstRow();
+
+	/**
+	 * @return last row in the range (x2 in x1,y1-x2,y2)
+	 */
+	public int getLastRow();
+
+	/**
+	 * @return the first column number in the area.
+	 */
+	public int getFirstColumn();
+
+	/**
+	 * @return lastcolumn in the area
+	 */
+	public int getLastColumn();
+
+	class OffsetArea implements AreaI {
+
+		private final int _firstColumn;
+		private final int _firstRow;
+		private final int _lastColumn;
+		private final int _lastRow;
+
+		public OffsetArea(int baseRow, int baseColumn, int relFirstRowIx, int relLastRowIx,
+				int relFirstColIx, int relLastColIx) {
+			_firstRow = baseRow + relFirstRowIx;
+			_lastRow = baseRow + relLastRowIx;
+			_firstColumn = baseColumn + relFirstColIx;
+			_lastColumn = baseColumn + relLastColIx;
+		}
+
+		public int getFirstColumn() {
+			return _firstColumn;
+		}
+
+		public int getFirstRow() {
+			return _firstRow;
+		}
+
+		public int getLastColumn() {
+			return _lastColumn;
+		}
+
+		public int getLastRow() {
+			return _lastRow;
+		}
+	}
+
 }
\ No newline at end of file
diff --git a/src/java/org/apache/poi/hssf/record/formula/AreaNPtg.java b/src/java/org/apache/poi/hssf/record/formula/AreaNPtg.java
index bf013838b2..fc391b801d 100644
--- a/src/java/org/apache/poi/hssf/record/formula/AreaNPtg.java
+++ b/src/java/org/apache/poi/hssf/record/formula/AreaNPtg.java
@@ -23,7 +23,7 @@ import org.apache.poi.hssf.record.RecordInputStream;
  * Specifies a rectangular area of cells A1:A4 for instance.
  * @author Jason Height (jheight at chariot dot net dot au)
  */
-public final class AreaNPtg extends AreaPtgBase {
+public final class AreaNPtg extends Area2DPtgBase {
 	public final static short sid = 0x2D;
 
 	public AreaNPtg(RecordInputStream in) {
diff --git a/src/java/org/apache/poi/hssf/record/formula/AreaPtg.java b/src/java/org/apache/poi/hssf/record/formula/AreaPtg.java
index 0839e5570a..77e9fa0b5e 100755
--- a/src/java/org/apache/poi/hssf/record/formula/AreaPtg.java
+++ b/src/java/org/apache/poi/hssf/record/formula/AreaPtg.java
@@ -23,16 +23,16 @@ import org.apache.poi.hssf.record.RecordInputStream;
  * Specifies a rectangular area of cells A1:A4 for instance.
  * @author Jason Height (jheight at chariot dot net dot au)
  */
-public final class AreaPtg extends AreaPtgBase {
-    public final static short sid  = 0x25;
+public final class AreaPtg extends Area2DPtgBase {
+	public final static short sid  = 0x25;
 
-    public AreaPtg(int firstRow, int lastRow, int firstColumn, int lastColumn, boolean firstRowRelative, boolean lastRowRelative, boolean firstColRelative, boolean lastColRelative) {
-      super(firstRow, lastRow, firstColumn, lastColumn, firstRowRelative, lastRowRelative, firstColRelative, lastColRelative);
-    }
-    public AreaPtg(RecordInputStream in) {
-      super(in);
-    }
-    public AreaPtg(String arearef) {
+	public AreaPtg(int firstRow, int lastRow, int firstColumn, int lastColumn, boolean firstRowRelative, boolean lastRowRelative, boolean firstColRelative, boolean lastColRelative) {
+		super(firstRow, lastRow, firstColumn, lastColumn, firstRowRelative, lastRowRelative, firstColRelative, lastColRelative);
+	}
+	public AreaPtg(RecordInputStream in) {
+		super(in);
+	}
+	public AreaPtg(String arearef) {
 		super(arearef);
 	}
 	protected byte getSid() {
diff --git a/src/java/org/apache/poi/hssf/record/formula/AreaPtgBase.java b/src/java/org/apache/poi/hssf/record/formula/AreaPtgBase.java
index 9ac406b319..cf3d82cacf 100644
--- a/src/java/org/apache/poi/hssf/record/formula/AreaPtgBase.java
+++ b/src/java/org/apache/poi/hssf/record/formula/AreaPtgBase.java
@@ -23,7 +23,7 @@ import org.apache.poi.util.BitFieldFactory;
 
 import org.apache.poi.ss.util.CellReference;
 import org.apache.poi.ss.usermodel.Workbook;
-import org.apache.poi.hssf.util.AreaReference;
+import org.apache.poi.ss.util.AreaReference;
 import org.apache.poi.hssf.record.RecordInputStream;
 
 /**
@@ -37,11 +37,9 @@ public abstract class AreaPtgBase extends OperandPtg implements AreaI {
      * see similar comment in ReferencePtg
      */
     protected final RuntimeException notImplemented() {
-          return new RuntimeException("Coding Error: This method should never be called. This ptg should be converted");
+        return new RuntimeException("Coding Error: This method should never be called. This ptg should be converted");
     }
 
-    public final static short sid  = 0x25;
-    private final static int  SIZE = 9;
     /** zero based, unsigned 16 bit */
     private int             field_1_first_row;
     /** zero based, unsigned 16 bit */
@@ -55,6 +53,10 @@ public abstract class AreaPtgBase extends OperandPtg implements AreaI {
     private final static BitField   colRelative = BitFieldFactory.getInstance(0x4000);
     private final static BitField   columnMask      = BitFieldFactory.getInstance(0x3FFF);
 
+    protected AreaPtgBase() {
+        // do nothing
+    }
+    
     protected AreaPtgBase(String arearef) {
         AreaReference ar = new AreaReference(arearef);
         CellReference firstCell = ar.getFirstCell();
@@ -97,35 +99,17 @@ public abstract class AreaPtgBase extends OperandPtg implements AreaI {
         }
     }
 
-    protected AreaPtgBase(RecordInputStream in)
-    {
-        field_1_first_row    = in.readUShort();
-        field_2_last_row     = in.readUShort();
+    protected final void readCoordinates(RecordInputStream in) {
+        field_1_first_row = in.readUShort();
+        field_2_last_row = in.readUShort();
         field_3_first_column = in.readUShort();
-        field_4_last_column  = in.readUShort();
-    }
-
-    public final String toString() {
-        StringBuffer sb = new StringBuffer();
-        sb.append(getClass().getName());
-        sb.append(" [");
-        sb.append(AreaReference.formatAsString(this));
-        sb.append("]");
-        return sb.toString();
+        field_4_last_column = in.readUShort();
     }
-    protected abstract byte getSid();
-
-    public final void writeBytes(byte [] array, int offset) {
-        array[offset] = (byte) (getSid() + getPtgClass());
-        LittleEndian.putShort(array,offset+1,(short)field_1_first_row);
-        LittleEndian.putShort(array,offset+3,(short)field_2_last_row);
-        LittleEndian.putShort(array,offset+5,(short)field_3_first_column);
-        LittleEndian.putShort(array,offset+7,(short)field_4_last_column);        
-    }
-
-    
-    public final int getSize() {
-        return SIZE;
+    protected final void writeCoordinates(byte[] array, int offset) {
+        LittleEndian.putUShort(array, offset + 0, field_1_first_row);
+        LittleEndian.putUShort(array, offset + 2, field_2_last_row);
+        LittleEndian.putUShort(array, offset + 4, field_3_first_column);
+        LittleEndian.putUShort(array, offset + 6, field_4_last_column);        
     }
 
     /**
@@ -207,7 +191,7 @@ public abstract class AreaPtgBase extends OperandPtg implements AreaI {
      */
     public final void setFirstColumn(int colIx) {
         checkColumnBounds(colIx);
-    	field_3_first_column=columnMask.setValue(field_3_first_column, colIx);
+        field_3_first_column=columnMask.setValue(field_3_first_column, colIx);
     }
 
     /**
@@ -266,7 +250,7 @@ public abstract class AreaPtgBase extends OperandPtg implements AreaI {
      */
     public final void setLastColumn(int colIx) {
         checkColumnBounds(colIx);
-    	field_4_last_column=columnMask.setValue(field_4_last_column, colIx);
+        field_4_last_column=columnMask.setValue(field_4_last_column, colIx);
     }
 
     /**
@@ -275,9 +259,18 @@ public abstract class AreaPtgBase extends OperandPtg implements AreaI {
     public final void setLastColumnRaw(short column) {
         field_4_last_column = column;
     }
+    protected final String formatReferenceAsString() {
+        CellReference topLeft = new CellReference(getFirstRow(),getFirstColumn(),!isFirstRowRelative(),!isFirstColRelative());
+        CellReference botRight = new CellReference(getLastRow(),getLastColumn(),!isLastRowRelative(),!isLastColRelative());
+        
+        if(AreaReference.isWholeColumnReference(topLeft, botRight)) {
+            return (new AreaReference(topLeft, botRight)).formatAsString();
+        }
+        return topLeft.formatAsString() + ":" + botRight.formatAsString(); 
+    }
     
     public String toFormulaString(Workbook book) {
-        return AreaReference.formatAsString(this);
+        return formatReferenceAsString();
     }
 
     public byte getDefaultOperandClass() {
diff --git a/src/java/org/apache/poi/hssf/record/formula/RefPtgBase.java b/src/java/org/apache/poi/hssf/record/formula/RefPtgBase.java
index 87207f6a07..33dff9ec04 100644
--- a/src/java/org/apache/poi/hssf/record/formula/RefPtgBase.java
+++ b/src/java/org/apache/poi/hssf/record/formula/RefPtgBase.java
@@ -131,14 +131,6 @@ public abstract class RefPtgBase extends OperandPtg {
         field_2_col=colRelative.setBoolean(field_2_col,rel);
     }
 
-    public final void setColumnRawX(int col) { // TODO
-        field_2_col = col;
-    }
-
-    public int getColumnRawX() { // TODO
-        return field_2_col;
-    }
-
     public final void setColumn(int col) {
         if(col < 0 || col >= 0x100) {
             throw new IllegalArgumentException("Specified colIx (" + col + ") is out of range");
diff --git a/src/java/org/apache/poi/hssf/record/formula/eval/Area2DEval.java b/src/java/org/apache/poi/hssf/record/formula/eval/Area2DEval.java
deleted file mode 100644
index 5ae98b39fe..0000000000
--- a/src/java/org/apache/poi/hssf/record/formula/eval/Area2DEval.java
+++ /dev/null
@@ -1,32 +0,0 @@
-/*
-* Licensed to the Apache Software Foundation (ASF) under one or more
-* contributor license agreements.  See the NOTICE file distributed with
-* this work for additional information regarding copyright ownership.
-* The ASF licenses this file to You under the Apache License, Version 2.0
-* (the "License"); you may not use this file except in compliance with
-* the License.  You may obtain a copy of the License at
-*
-*     http://www.apache.org/licenses/LICENSE-2.0
-*
-* Unless required by applicable law or agreed to in writing, software
-* distributed under the License is distributed on an "AS IS" BASIS,
-* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-* See the License for the specific language governing permissions and
-* limitations under the License.
-*/
-
-package org.apache.poi.hssf.record.formula.eval;
-
-import org.apache.poi.hssf.record.formula.AreaPtg;
-import org.apache.poi.hssf.record.formula.Ptg;
-
-/**
- * @author Amol S. Deshmukh &lt; amolweb at ya hoo dot com &gt;
- * 
- */
-public final class Area2DEval extends AreaEvalBase {
-
-	public Area2DEval(Ptg ptg, ValueEval[] values) {
-		super((AreaPtg) ptg, values);
-	}
-}
\ No newline at end of file
diff --git a/src/java/org/apache/poi/hssf/record/formula/eval/Area3DEval.java b/src/java/org/apache/poi/hssf/record/formula/eval/Area3DEval.java
deleted file mode 100644
index 89209e21b6..0000000000
--- a/src/java/org/apache/poi/hssf/record/formula/eval/Area3DEval.java
+++ /dev/null
@@ -1,39 +0,0 @@
-/*
-* Licensed to the Apache Software Foundation (ASF) under one or more
-* contributor license agreements.  See the NOTICE file distributed with
-* this work for additional information regarding copyright ownership.
-* The ASF licenses this file to You under the Apache License, Version 2.0
-* (the "License"); you may not use this file except in compliance with
-* the License.  You may obtain a copy of the License at
-*
-*     http://www.apache.org/licenses/LICENSE-2.0
-*
-* Unless required by applicable law or agreed to in writing, software
-* distributed under the License is distributed on an "AS IS" BASIS,
-* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-* See the License for the specific language governing permissions and
-* limitations under the License.
-*/
-
-package org.apache.poi.hssf.record.formula.eval;
-
-import org.apache.poi.hssf.record.formula.Area3DPtg;
-import org.apache.poi.hssf.record.formula.Ptg;
-
-/**
- * @author Amol S. Deshmukh &lt; amolweb at ya hoo dot com &gt;
- * 
- */
-public final class Area3DEval extends AreaEvalBase {
-
-	private final int _externSheetIndex;
-
-	public Area3DEval(Ptg ptg, ValueEval[] values) {
-		super((Area3DPtg) ptg, values);
-		_externSheetIndex = ((Area3DPtg) ptg).getExternSheetIndex();
-	}
-
-	public int getExternSheetIndex() {
-		return _externSheetIndex;
-	}
-}
diff --git a/src/java/org/apache/poi/hssf/record/formula/eval/AreaEval.java b/src/java/org/apache/poi/hssf/record/formula/eval/AreaEval.java
index 182b9b618b..b528eb784e 100644
--- a/src/java/org/apache/poi/hssf/record/formula/eval/AreaEval.java
+++ b/src/java/org/apache/poi/hssf/record/formula/eval/AreaEval.java
@@ -62,13 +62,6 @@ public interface AreaEval extends ValueEval {
     boolean isColumn();
 
     /**
-     * The array of values  in this area. Although the area
-     * maybe 1D (ie. isRow() or isColumn() returns true) or 2D
-     * the returned array is 1D.
-     */
-    ValueEval[] getValues();
-
-    /**
      * @return the ValueEval from within this area at the specified row and col index. Never 
      * <code>null</code> (possibly {@link BlankEval}).  The specified indexes should be absolute 
      * indexes in the sheet and not relative indexes within the area.  
@@ -104,4 +97,10 @@ public interface AreaEval extends ValueEval {
      * specified indexes should relative to the top left corner of this area.  
      */
     ValueEval getRelativeValue(int relativeRowIndex, int relativeColumnIndex);
+
+    /**
+     * Creates an {@link AreaEval} offset by a relative amount from from the upper left cell
+     * of this area
+     */
+    AreaEval offset(int relFirstRowIx, int relLastRowIx, int relFirstColIx, int relLastColIx);
 }
diff --git a/src/java/org/apache/poi/hssf/record/formula/eval/AreaEvalBase.java b/src/java/org/apache/poi/hssf/record/formula/eval/AreaEvalBase.java
index 1686e75f33..94f6c9fe4a 100644
--- a/src/java/org/apache/poi/hssf/record/formula/eval/AreaEvalBase.java
+++ b/src/java/org/apache/poi/hssf/record/formula/eval/AreaEvalBase.java
@@ -22,20 +22,16 @@ import org.apache.poi.hssf.record.formula.AreaI;
 /**
  * @author Josh Micich
  */
-abstract class AreaEvalBase implements AreaEval {
+public abstract class AreaEvalBase implements AreaEval {
 
 	private final int _firstColumn;
 	private final int _firstRow;
 	private final int _lastColumn;
 	private final int _lastRow;
-	private final ValueEval[] _values;
 	private final int _nColumns;
 	private final int _nRows;
 
-	protected AreaEvalBase(AreaI ptg, ValueEval[] values) {
-		if (values == null) {
-			throw new IllegalArgumentException("values must not be null");
-		}
+	protected AreaEvalBase(AreaI ptg) {
 		_firstRow = ptg.getFirstRow();
 		_firstColumn = ptg.getFirstColumn();
 		_lastRow = ptg.getLastRow();
@@ -43,22 +39,6 @@ abstract class AreaEvalBase implements AreaEval {
 		
 		_nColumns = _lastColumn - _firstColumn + 1;
 		_nRows = _lastRow - _firstRow + 1;
-		
-		int expectedItemCount = _nRows * _nColumns;
-		if ((values.length != expectedItemCount)) {
-			// Note - this math may need alteration when POI starts to support full column or full row refs
-			throw new IllegalArgumentException("Array size should be (" + expectedItemCount
-					+ ") but was (" + values.length + ")");
-		}
-		
-
-
-		for (int i = values.length - 1; i >= 0; i--) {
-			if (values[i] == null) {
-				throw new IllegalArgumentException("value array elements must not be null");
-			}
-		}
-		_values = values;
 	}
 
 	public final int getFirstColumn() {
@@ -77,11 +57,6 @@ abstract class AreaEvalBase implements AreaEval {
 		return _lastRow;
 	}
 
-	public final ValueEval[] getValues() {
-		// TODO - clone() - but some junits rely on not cloning at the moment
-		return _values;
-	}
-
 	public final ValueEval getValueAt(int row, int col) {
 		int rowOffsetIx = row - _firstRow;
 		int colOffsetIx = col - _firstColumn;
@@ -121,14 +96,7 @@ abstract class AreaEvalBase implements AreaEval {
 		return _lastRow-_firstRow+1;
 	}
 
-	public ValueEval getRelativeValue(int relativeRowIndex, int relativeColumnIndex) {
-		int index = relativeRowIndex * _nColumns + relativeColumnIndex;
-		ValueEval result = _values[index];
-		if (result == null) {
-			return BlankEval.INSTANCE;
-		}
-		return result;
-	}
+	public abstract ValueEval getRelativeValue(int relativeRowIndex, int relativeColumnIndex);
 
 	public int getWidth() {
 		return _lastColumn-_firstColumn+1;
diff --git a/src/java/org/apache/poi/hssf/record/formula/eval/FunctionEval.java b/src/java/org/apache/poi/hssf/record/formula/eval/FunctionEval.java
index 533c604a0c..fe58c69c09 100644
--- a/src/java/org/apache/poi/hssf/record/formula/eval/FunctionEval.java
+++ b/src/java/org/apache/poi/hssf/record/formula/eval/FunctionEval.java
@@ -50,7 +50,6 @@ public abstract class FunctionEval implements OperationEval {
      
     static {
         Map m = new HashMap();
-        addMapping(m, ID.OFFSET, new Offset());
         addMapping(m, ID.INDIRECT, new Indirect());
         addMapping(m, ID.EXTERNAL_FUNC, new ExternalFunction());
         freeRefFunctionsByIdMap = m;
@@ -155,7 +154,7 @@ public abstract class FunctionEval implements OperationEval {
         retval[75] = new Areas(); // AREAS
         retval[76] = new Rows(); // ROWS
         retval[77] = new Columns(); // COLUMNS
-        retval[ID.OFFSET] = null; // Offset.evaluate has a different signature
+        retval[ID.OFFSET] = new Offset(); // OFFSET
         retval[79] = new Absref(); // ABSREF
         retval[80] = new Relref(); // RELREF
         retval[81] = new Argument(); // ARGUMENT
diff --git a/src/java/org/apache/poi/hssf/record/formula/eval/LazyAreaEval.java b/src/java/org/apache/poi/hssf/record/formula/eval/LazyAreaEval.java
new file mode 100644
index 0000000000..b5c6336170
--- /dev/null
+++ b/src/java/org/apache/poi/hssf/record/formula/eval/LazyAreaEval.java
@@ -0,0 +1,65 @@
+/*
+* Licensed to the Apache Software Foundation (ASF) under one or more
+* contributor license agreements.  See the NOTICE file distributed with
+* this work for additional information regarding copyright ownership.
+* The ASF licenses this file to You under the Apache License, Version 2.0
+* (the "License"); you may not use this file except in compliance with
+* the License.  You may obtain a copy of the License at
+*
+*     http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+package org.apache.poi.hssf.record.formula.eval;
+
+import org.apache.poi.hssf.record.formula.AreaI;
+import org.apache.poi.hssf.record.formula.AreaI.OffsetArea;
+import org.apache.poi.ss.usermodel.Cell;
+import org.apache.poi.ss.usermodel.FormulaEvaluator;
+import org.apache.poi.ss.usermodel.Row;
+import org.apache.poi.ss.usermodel.Sheet;
+import org.apache.poi.ss.usermodel.Workbook;
+
+/**
+ * @author Amol S. Deshmukh &lt; amolweb at ya hoo dot com &gt;
+ * 
+ */
+public final class LazyAreaEval extends AreaEvalBase {
+
+	private final Sheet _sheet;
+	private Workbook _workbook;
+
+	public LazyAreaEval(AreaI ptg, Sheet sheet, Workbook workbook) {
+		super(ptg);
+		_sheet = sheet;
+		_workbook = workbook;
+	}
+
+	public ValueEval getRelativeValue(int relativeRowIndex, int relativeColumnIndex) { 
+		
+		int rowIx = (relativeRowIndex + getFirstRow() ) & 0xFFFF;
+		int colIx = (relativeColumnIndex + getFirstColumn() ) & 0x00FF;
+		
+		Row row = _sheet.getRow(rowIx);
+		if (row == null) {
+			return BlankEval.INSTANCE;
+		}
+		Cell cell = row.getCell(colIx);
+		if (cell == null) {
+			return BlankEval.INSTANCE;
+		}
+		return FormulaEvaluator.getEvalForCell(cell, _sheet, _workbook);
+	}
+
+	public AreaEval offset(int relFirstRowIx, int relLastRowIx, int relFirstColIx, int relLastColIx) {
+		AreaI area = new OffsetArea(getFirstRow(), getFirstColumn(),
+				relFirstRowIx, relLastRowIx, relFirstColIx, relLastColIx);
+
+		return new LazyAreaEval(area, _sheet, _workbook);
+	}
+}
diff --git a/src/java/org/apache/poi/hssf/record/formula/eval/LazyRefEval.java b/src/java/org/apache/poi/hssf/record/formula/eval/LazyRefEval.java
new file mode 100644
index 0000000000..7daf964240
--- /dev/null
+++ b/src/java/org/apache/poi/hssf/record/formula/eval/LazyRefEval.java
@@ -0,0 +1,52 @@
+package org.apache.poi.hssf.record.formula.eval;

+

+import org.apache.poi.hssf.record.formula.AreaI;

+import org.apache.poi.hssf.record.formula.AreaI.OffsetArea;

+import org.apache.poi.hssf.record.formula.Ref3DPtg;

+import org.apache.poi.hssf.record.formula.RefPtg;

+import org.apache.poi.ss.usermodel.Cell;

+import org.apache.poi.ss.usermodel.FormulaEvaluator;

+import org.apache.poi.ss.usermodel.Row;

+import org.apache.poi.ss.usermodel.Sheet;

+import org.apache.poi.ss.usermodel.Workbook;

+

+public final class LazyRefEval extends RefEvalBase {

+

+	private final Sheet _sheet;

+	private final Workbook _workbook;

+

+

+	public LazyRefEval(RefPtg ptg, Sheet sheet, Workbook workbook) {

+		super(ptg.getRow(), ptg.getColumn());

+		_sheet = sheet;

+		_workbook = workbook;

+	}

+	public LazyRefEval(Ref3DPtg ptg, Sheet sheet, Workbook workbook) {

+		super(ptg.getRow(), ptg.getColumn());

+		_sheet = sheet;

+		_workbook = workbook;

+	}

+

+	public ValueEval getInnerValueEval() {

+		int rowIx = getRow();

+		int colIx = getColumn();

+		

+		Row row = _sheet.getRow(rowIx);

+		if (row == null) {

+			return BlankEval.INSTANCE;

+		}

+		Cell cell = row.getCell(colIx);

+		if (cell == null) {

+			return BlankEval.INSTANCE;

+		}

+		return FormulaEvaluator.getEvalForCell(cell, _sheet, _workbook);

+	}

+	

+	public AreaEval offset(int relFirstRowIx, int relLastRowIx, int relFirstColIx, int relLastColIx) {

+		

+		AreaI area = new OffsetArea(getRow(), getColumn(),

+				relFirstRowIx, relLastRowIx, relFirstColIx, relLastColIx);

+

+		return new LazyAreaEval(area, _sheet, _workbook);

+	}

+}

diff --git a/src/java/org/apache/poi/hssf/record/formula/eval/NumberEval.java b/src/java/org/apache/poi/hssf/record/formula/eval/NumberEval.java
index 44a017f631..e22957bd4a 100644
--- a/src/java/org/apache/poi/hssf/record/formula/eval/NumberEval.java
+++ b/src/java/org/apache/poi/hssf/record/formula/eval/NumberEval.java
@@ -69,5 +69,11 @@ public class NumberEval implements NumericValueEval, StringValueEval {
             }
         }
     }
-    
+    public final String toString() {
+        StringBuffer sb = new StringBuffer(64);
+        sb.append(getClass().getName()).append(" [");
+        sb.append(getStringValue());
+        sb.append("]");
+        return sb.toString();
+    }
 }
diff --git a/src/java/org/apache/poi/hssf/record/formula/eval/Ref2DEval.java b/src/java/org/apache/poi/hssf/record/formula/eval/Ref2DEval.java
index 033ecc1f86..e4bb47a43d 100644
--- a/src/java/org/apache/poi/hssf/record/formula/eval/Ref2DEval.java
+++ b/src/java/org/apache/poi/hssf/record/formula/eval/Ref2DEval.java
@@ -47,4 +47,7 @@ public final class Ref2DEval implements RefEval {
     public int getColumn() {
         return delegate.getColumn();
     }
+    public AreaEval offset(int relFirstRowIx, int relLastRowIx, int relFirstColIx, int relLastColIx) {
+        throw new RuntimeException("should not be called"); // TODO - delete this whole class
+    }
 }
diff --git a/src/java/org/apache/poi/hssf/record/formula/eval/Ref3DEval.java b/src/java/org/apache/poi/hssf/record/formula/eval/Ref3DEval.java
deleted file mode 100644
index 622d686329..0000000000
--- a/src/java/org/apache/poi/hssf/record/formula/eval/Ref3DEval.java
+++ /dev/null
@@ -1,53 +0,0 @@
-/*
-* Licensed to the Apache Software Foundation (ASF) under one or more
-* contributor license agreements.  See the NOTICE file distributed with
-* this work for additional information regarding copyright ownership.
-* The ASF licenses this file to You under the Apache License, Version 2.0
-* (the "License"); you may not use this file except in compliance with
-* the License.  You may obtain a copy of the License at
-*
-*     http://www.apache.org/licenses/LICENSE-2.0
-*
-* Unless required by applicable law or agreed to in writing, software
-* distributed under the License is distributed on an "AS IS" BASIS,
-* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-* See the License for the specific language governing permissions and
-* limitations under the License.
-*/
-
-package org.apache.poi.hssf.record.formula.eval;
-
-import org.apache.poi.hssf.record.formula.Ref3DPtg;
-
-/**
- * @author Amol S. Deshmukh
- *  
- */
-public final class Ref3DEval implements RefEval {
-
-    private final ValueEval value;
-    private final Ref3DPtg delegate;
-
-    public Ref3DEval(Ref3DPtg ptg, ValueEval ve) {
-        if(ve == null) {
-            throw new IllegalArgumentException("ve must not be null");
-        }
-        if(ptg == null) {
-            throw new IllegalArgumentException("ptg must not be null");
-        }
-        value = ve;
-        delegate = ptg;
-    }
-    public ValueEval getInnerValueEval() {
-        return value;
-    }
-    public int getRow() {
-        return delegate.getRow();
-    }
-    public int getColumn() {
-        return delegate.getColumn();
-    }
-    public int getExternSheetIndex() {
-        return delegate.getExternSheetIndex();
-    }
-}
diff --git a/src/java/org/apache/poi/hssf/record/formula/eval/RefEval.java b/src/java/org/apache/poi/hssf/record/formula/eval/RefEval.java
index e462586d72..397d1f1c94 100644
--- a/src/java/org/apache/poi/hssf/record/formula/eval/RefEval.java
+++ b/src/java/org/apache/poi/hssf/record/formula/eval/RefEval.java
@@ -1,19 +1,19 @@
-/*
-* Licensed to the Apache Software Foundation (ASF) under one or more
-* contributor license agreements.  See the NOTICE file distributed with
-* this work for additional information regarding copyright ownership.
-* The ASF licenses this file to You under the Apache License, Version 2.0
-* (the "License"); you may not use this file except in compliance with
-* the License.  You may obtain a copy of the License at
-*
-*     http://www.apache.org/licenses/LICENSE-2.0
-*
-* Unless required by applicable law or agreed to in writing, software
-* distributed under the License is distributed on an "AS IS" BASIS,
-* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-* See the License for the specific language governing permissions and
-* limitations under the License.
-*/
+/* ====================================================================
+   Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF licenses this file to You under the Apache License, Version 2.0
+   (the "License"); you may not use this file except in compliance with
+   the License.  You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+==================================================================== */
 
 package org.apache.poi.hssf.record.formula.eval;
 
@@ -30,22 +30,22 @@ package org.apache.poi.hssf.record.formula.eval;
 public interface RefEval extends ValueEval {
 
     /**
-     * The (possibly evaluated) ValueEval contained
-     * in this RefEval. eg. if cell A1 contains "test"
-     * then in a formula referring to cell A1 
-     * the RefEval representing
-     * A1 will return as the getInnerValueEval() the
-     * object of concrete type StringEval
+     * @return the evaluated value of the cell referred to by this RefEval.
      */
-    public ValueEval getInnerValueEval();
+    ValueEval getInnerValueEval();
 
     /**
      * returns the zero based column index.
      */
-    public int getColumn();
+    int getColumn();
 
     /**
      * returns the zero based row index.
      */
-    public int getRow();
+    int getRow();
+
+    /**
+     * Creates an {@link AreaEval} offset by a relative amount from this RefEval
+     */
+    AreaEval offset(int relFirstRowIx, int relLastRowIx, int relFirstColIx, int relLastColIx);
 }
diff --git a/src/java/org/apache/poi/hssf/record/formula/eval/RefEvalBase.java b/src/java/org/apache/poi/hssf/record/formula/eval/RefEvalBase.java
new file mode 100644
index 0000000000..37d20f8082
--- /dev/null
+++ b/src/java/org/apache/poi/hssf/record/formula/eval/RefEvalBase.java
@@ -0,0 +1,18 @@
+package org.apache.poi.hssf.record.formula.eval;

+

+public abstract class RefEvalBase implements RefEval {

+

+	private final int _rowIndex;

+	private final int _columnIndex;

+

+	protected RefEvalBase(int rowIndex, int columnIndex) {

+		_rowIndex = rowIndex;

+		_columnIndex = columnIndex;

+	}

+	public final int getRow() {

+		return _rowIndex;

+	}

+	public final int getColumn() {

+		return _columnIndex;

+	}

+}

diff --git a/src/java/org/apache/poi/hssf/record/formula/functions/CountUtils.java b/src/java/org/apache/poi/hssf/record/formula/functions/CountUtils.java
index f8d8883825..27dfcc1b64 100644
--- a/src/java/org/apache/poi/hssf/record/formula/functions/CountUtils.java
+++ b/src/java/org/apache/poi/hssf/record/formula/functions/CountUtils.java
@@ -50,9 +50,9 @@ final class CountUtils {
 		for (int rrIx=0; rrIx<height; rrIx++) {
 			for (int rcIx=0; rcIx<width; rcIx++) {
 				ValueEval ve = areaEval.getRelativeValue(rrIx, rcIx);
-    			if(criteriaPredicate.matches(ve)) {
-    				result++;
-    			}
+				if(criteriaPredicate.matches(ve)) {
+					result++;
+				}
 			}
 		}
 		return result;
@@ -67,6 +67,9 @@ final class CountUtils {
 		return 0;
 	}
 	public static int countArg(Eval eval, I_MatchPredicate criteriaPredicate) {
+		if (eval == null) {
+			throw new IllegalArgumentException("eval must not be null");
+		}
 		if (eval instanceof AreaEval) {
 			return CountUtils.countMatchingCellsInArea((AreaEval) eval, criteriaPredicate);
 		}
diff --git a/src/java/org/apache/poi/hssf/record/formula/functions/If.java b/src/java/org/apache/poi/hssf/record/formula/functions/If.java
index 7aba5db72a..4b066b8226 100644
--- a/src/java/org/apache/poi/hssf/record/formula/functions/If.java
+++ b/src/java/org/apache/poi/hssf/record/formula/functions/If.java
@@ -1,28 +1,28 @@
-/*
-* Licensed to the Apache Software Foundation (ASF) under one or more
-* contributor license agreements.  See the NOTICE file distributed with
-* this work for additional information regarding copyright ownership.
-* The ASF licenses this file to You under the Apache License, Version 2.0
-* (the "License"); you may not use this file except in compliance with
-* the License.  You may obtain a copy of the License at
-*
-*     http://www.apache.org/licenses/LICENSE-2.0
-*
-* Unless required by applicable law or agreed to in writing, software
-* distributed under the License is distributed on an "AS IS" BASIS,
-* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-* See the License for the specific language governing permissions and
-* limitations under the License.
-*/
-/*
- * Created on Nov 25, 2006
- *
- */
+/* ====================================================================
+   Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF licenses this file to You under the Apache License, Version 2.0
+   (the "License"); you may not use this file except in compliance with
+   the License.  You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+==================================================================== */
+
 package org.apache.poi.hssf.record.formula.functions;
 
 import org.apache.poi.hssf.record.formula.eval.BoolEval;
 import org.apache.poi.hssf.record.formula.eval.ErrorEval;
 import org.apache.poi.hssf.record.formula.eval.Eval;
+import org.apache.poi.hssf.record.formula.eval.EvaluationException;
+import org.apache.poi.hssf.record.formula.eval.OperandResolver;
+import org.apache.poi.hssf.record.formula.eval.ValueEval;
 
 /**
  * @author Amol S. Deshmukh &lt; amolweb at ya hoo dot com &gt;
@@ -30,20 +30,37 @@ import org.apache.poi.hssf.record.formula.eval.Eval;
  */
 public final class If implements Function {
 
-    public Eval evaluate(Eval[] args, int srcCellRow, short srcCellCol) {
+	public Eval evaluate(Eval[] args, int srcCellRow, short srcCellCol) {
+		Eval falseResult;
+		switch (args.length) {
+			case 3:
+				falseResult = args[2];
+				break;
+			case 2:
+				falseResult = BoolEval.FALSE;
+				break;
+			default:
+				return ErrorEval.VALUE_INVALID;
+		}
+		boolean b;
+		try {
+			b = evaluateFirstArg(args[0], srcCellRow, srcCellCol);
+		} catch (EvaluationException e) {
+			return e.getErrorEval();
+		}
+		if (b) {
+			return args[1];
+		}
+		return falseResult;
+	}
 
-        Eval evalWhenFalse = BoolEval.FALSE;
-        switch (args.length) {
-        case 3:
-            evalWhenFalse = args[2];
-        case 2:
-            BoolEval beval = (BoolEval) args[0]; // TODO - class cast exception
-            if (beval.getBooleanValue()) {
-                return args[1];
-            }
-            return evalWhenFalse;
-        default:
-            return ErrorEval.VALUE_INVALID;
-        }
-    }
+	private static boolean evaluateFirstArg(Eval arg, int srcCellRow, short srcCellCol)
+			throws EvaluationException {
+		ValueEval ve = OperandResolver.getSingleValue(arg, srcCellRow, srcCellCol);
+		Boolean b = OperandResolver.coerceValueToBoolean(ve, false);
+		if (b == null) {
+			return false;
+		}
+		return b.booleanValue();
+	}
 }
diff --git a/src/java/org/apache/poi/hssf/record/formula/functions/Index.java b/src/java/org/apache/poi/hssf/record/formula/functions/Index.java
index aebf6aab0d..3c93c0846b 100644
--- a/src/java/org/apache/poi/hssf/record/formula/functions/Index.java
+++ b/src/java/org/apache/poi/hssf/record/formula/functions/Index.java
@@ -1,28 +1,28 @@
-/*
-* Licensed to the Apache Software Foundation (ASF) under one or more
-* contributor license agreements.  See the NOTICE file distributed with
-* this work for additional information regarding copyright ownership.
-* The ASF licenses this file to You under the Apache License, Version 2.0
-* (the "License"); you may not use this file except in compliance with
-* the License.  You may obtain a copy of the License at
-*
-*     http://www.apache.org/licenses/LICENSE-2.0
-*
-* Unless required by applicable law or agreed to in writing, software
-* distributed under the License is distributed on an "AS IS" BASIS,
-* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-* See the License for the specific language governing permissions and
-* limitations under the License.
-*/
+/* ====================================================================
+   Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF licenses this file to You under the Apache License, Version 2.0
+   (the "License"); you may not use this file except in compliance with
+   the License.  You may obtain a copy of the License at
 
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+==================================================================== */
 
 package org.apache.poi.hssf.record.formula.functions;
 
 import org.apache.poi.hssf.record.formula.eval.AreaEval;
 import org.apache.poi.hssf.record.formula.eval.ErrorEval;
 import org.apache.poi.hssf.record.formula.eval.Eval;
-import org.apache.poi.hssf.record.formula.eval.NumberEval;
-import org.apache.poi.hssf.record.formula.eval.RefEval;
+import org.apache.poi.hssf.record.formula.eval.EvaluationException;
+import org.apache.poi.hssf.record.formula.eval.OperandResolver;
+import org.apache.poi.hssf.record.formula.eval.ValueEval;
 
 /**
  * Implementation for the Excel function INDEX<p/>
@@ -51,15 +51,23 @@ public final class Index implements Function {
 			return ErrorEval.VALUE_INVALID;
 		}
 		Eval firstArg = args[0];
-		if(firstArg instanceof AreaEval) {
-			AreaEval reference = (AreaEval) firstArg;
+		if(!(firstArg instanceof AreaEval)) {
+			
+			// else the other variation of this function takes an array as the first argument
+			// it seems like interface 'ArrayEval' does not even exist yet
 			
-			int rowIx = 0;
-			int columnIx = 0;
-			int areaIx = 0;
+			throw new RuntimeException("Incomplete code - cannot handle first arg of type ("
+					+ firstArg.getClass().getName() + ")");
+		}
+		AreaEval reference = (AreaEval) firstArg;
+		
+		int rowIx = 0;
+		int columnIx = 0;
+		int areaIx = 0;
+		try {	
 			switch(nArgs) {
 				case 4:
-					areaIx = convertIndexArgToZeroBase(args[3]);
+					areaIx = convertIndexArgToZeroBase(args[3], srcCellRow, srcCellCol);
 					throw new RuntimeException("Incomplete code" +
 							" - don't know how to support the 'area_num' parameter yet)");
 					// Excel expression might look like this "INDEX( (A1:B4, C3:D6, D2:E5 ), 1, 2, 3)
@@ -68,41 +76,41 @@ public final class Index implements Function {
 					// The formula parser doesn't seem to support this yet. Not sure if the evaluator does either
 					
 				case 3:
-					columnIx = convertIndexArgToZeroBase(args[2]);
+					columnIx = convertIndexArgToZeroBase(args[2], srcCellRow, srcCellCol);
 				case 2:
-					rowIx = convertIndexArgToZeroBase(args[1]);
+					rowIx = convertIndexArgToZeroBase(args[1], srcCellRow, srcCellCol);
 					break;
 				default:
 					// too many arguments
 					return ErrorEval.VALUE_INVALID;
 			}
-			
-	        int nColumns = reference.getLastColumn()-reference.getFirstColumn()+1;
-			int index = rowIx * nColumns + columnIx;
-			
-			return reference.getValues()[index];
+			return getValueFromArea(reference, rowIx, columnIx);
+		} catch (EvaluationException e) {
+			return e.getErrorEval();
 		}
-		
-		// else the other variation of this function takes an array as the first argument
-		// it seems like interface 'ArrayEval' does not even exist yet
-		
-		throw new RuntimeException("Incomplete code - cannot handle first arg of type ("
-				+ firstArg.getClass().getName() + ")");
 	}
 	
+	private static ValueEval getValueFromArea(AreaEval ae, int rowIx, int columnIx) throws EvaluationException {
+		int width = ae.getWidth();
+		int height = ae.getHeight();
+		
+		// Slightly irregular logic for bounds checking errors
+		if (rowIx >= height || columnIx >= width) {
+			throw new EvaluationException(ErrorEval.REF_INVALID);
+		}
+		if (rowIx < 0 || columnIx < 0) {
+			throw new EvaluationException(ErrorEval.VALUE_INVALID);
+		}
+		return ae.getRelativeValue(rowIx, columnIx);
+	}
+
 	/**
 	 * takes a NumberEval representing a 1-based index and returns the zero-based int value
 	 */
-	private static int convertIndexArgToZeroBase(Eval ev) {
-		NumberEval ne;
-		if(ev instanceof RefEval) {
-			// TODO - write junit to justify this
-			RefEval re = (RefEval) ev;
-			ne = (NumberEval) re.getInnerValueEval();
-		} else {
-			ne = (NumberEval)ev;
-		}
+	private static int convertIndexArgToZeroBase(Eval arg, int srcCellRow, short srcCellCol) throws EvaluationException {
 		
-		return (int)ne.getNumberValue() - 1;
+		ValueEval ev = OperandResolver.getSingleValue(arg, srcCellRow, srcCellCol);
+		int oneBasedVal = OperandResolver.coerceValueToInt(ev);
+		return oneBasedVal - 1;
 	}
 }
diff --git a/src/java/org/apache/poi/hssf/record/formula/functions/LookupUtils.java b/src/java/org/apache/poi/hssf/record/formula/functions/LookupUtils.java
index e8c083dc5a..e6a3ec81c2 100644
--- a/src/java/org/apache/poi/hssf/record/formula/functions/LookupUtils.java
+++ b/src/java/org/apache/poi/hssf/record/formula/functions/LookupUtils.java
@@ -17,8 +17,6 @@
 
 package org.apache.poi.hssf.record.formula.functions;
 
-import org.apache.poi.hssf.record.formula.AreaPtg;
-import org.apache.poi.hssf.record.formula.eval.Area2DEval;
 import org.apache.poi.hssf.record.formula.eval.AreaEval;
 import org.apache.poi.hssf.record.formula.eval.BlankEval;
 import org.apache.poi.hssf.record.formula.eval.BoolEval;
@@ -366,13 +364,7 @@ final class LookupUtils {
 			// Make this cell ref look like a 1x1 area ref.
 
 			// It doesn't matter if eval is a 2D or 3D ref, because that detail is never asked of AreaEval.
-			// This code only requires the value array item.
-			// anything would be ok for rowIx and colIx, but may as well get it right.
-			int rowIx = refEval.getRow();
-			int colIx = refEval.getColumn();
-			AreaPtg ap = new AreaPtg(rowIx, rowIx, colIx, colIx, false, false, false, false);
-			ValueEval value = refEval.getInnerValueEval();
-			return new Area2DEval(ap, new ValueEval[] { value, });
+			return refEval.offset(0, 0, 0, 0);
 		}
 		throw EvaluationException.invalidValue();
 	}
diff --git a/src/java/org/apache/poi/hssf/record/formula/functions/MathX.java b/src/java/org/apache/poi/hssf/record/formula/functions/MathX.java
index 593998f1e9..311707665e 100644
--- a/src/java/org/apache/poi/hssf/record/formula/functions/MathX.java
+++ b/src/java/org/apache/poi/hssf/record/formula/functions/MathX.java
@@ -455,85 +455,6 @@ public final class MathX {
         return d;
     }
     
-    /**
-     * returns the sum of difference of squares of corresponding double 
-     * value in each subarray: ie. sigma (xarr[i]^2-yarr[i]^2) 
-     * <br/>
-     * It is the responsibility of the caller 
-     * to ensure that the two subarrays are of equal length. If the 
-     * subarrays are not of equal length, the return value can be 
-     * unpredictable.
-     * @param xarr
-     * @param yarr
-     */
-    public static double sumx2my2(double[] xarr, double[] yarr) {
-        double d = 0;
-        
-        try {
-            for (int i=0, iSize=xarr.length; i<iSize; i++) {
-                d += (xarr[i] + yarr[i]) * (xarr[i] - yarr[i]);
-            }            
-        }
-        catch (ArrayIndexOutOfBoundsException ae) {
-            d = Double.NaN;
-        }
-        
-        return d;
-    }
-    
-    /**
-     * returns the sum of sum of squares of corresponding double 
-     * value in each subarray: ie. sigma (xarr[i]^2 + yarr[i]^2) 
-     * <br/>
-     * It is the responsibility of the caller 
-     * to ensure that the two subarrays are of equal length. If the 
-     * subarrays are not of equal length, the return value can be 
-     * unpredictable.
-     * @param xarr
-     * @param yarr
-     */
-    public static double sumx2py2(double[] xarr, double[] yarr) {
-        double d = 0;
-        
-        try {
-            for (int i=0, iSize=xarr.length; i<iSize; i++) {
-                d += (xarr[i] * xarr[i]) + (yarr[i] * yarr[i]);
-            }            
-        }
-        catch (ArrayIndexOutOfBoundsException ae) {
-            d = Double.NaN;
-        }
-        
-        return d;
-    }
-    
-
-    /**
-     * returns the sum of squares of difference of corresponding double 
-     * value in each subarray: ie. sigma ( (xarr[i]-yarr[i])^2 ) 
-     * <br/>
-     * It is the responsibility of the caller 
-     * to ensure that the two subarrays are of equal length. If the 
-     * subarrays are not of equal length, the return value can be 
-     * unpredictable.
-     * @param xarr
-     * @param yarr
-     */
-    public static double sumxmy2(double[] xarr, double[] yarr) {
-        double d = 0;
-        
-        try {
-            for (int i=0, iSize=xarr.length; i<iSize; i++) {
-                double t = (xarr[i] - yarr[i]);
-                d += t * t;
-            }            
-        }
-        catch (ArrayIndexOutOfBoundsException ae) {
-            d = Double.NaN;
-        }
-        
-        return d;
-    }
     
     /**
      * returns the total number of combinations possible when
diff --git a/src/java/org/apache/poi/hssf/record/formula/functions/MultiOperandNumericFunction.java b/src/java/org/apache/poi/hssf/record/formula/functions/MultiOperandNumericFunction.java
index 0e7cce217e..a9e98ae313 100644
--- a/src/java/org/apache/poi/hssf/record/formula/functions/MultiOperandNumericFunction.java
+++ b/src/java/org/apache/poi/hssf/record/formula/functions/MultiOperandNumericFunction.java
@@ -126,30 +126,34 @@ public abstract class MultiOperandNumericFunction extends NumericFunction {
         
         if (operand instanceof AreaEval) {
             AreaEval ae = (AreaEval) operand;
-            ValueEval[] values = ae.getValues();
             DoubleList retval = new DoubleList();
-            for (int j=0, jSize=values.length; j<jSize; j++) {
-                /*
-                 * TODO: For an AreaEval, we are constructing a RefEval
-                 * per element.
-                 * For now this is a tempfix solution since this may
-                 * require a more generic fix at the level of
-                 * HSSFFormulaEvaluator where we store an array
-                 * of RefEvals as the "values" array. 
-                 */
-                RefEval re = new Ref2DEval(null, values[j]);
-                ValueEval ve = singleOperandEvaluate(re, srcRow, srcCol);
-                
-                if (ve instanceof NumericValueEval) {
-                    NumericValueEval nve = (NumericValueEval) ve;
-                    retval.add(nve.getNumberValue());
-                }
-                else if (ve instanceof BlankEval) {
-                    // note - blanks are ignored, so returned array will be smaller.
-                } 
-                else {
-                    return null; // indicate to calling subclass that error occurred
-                }
+            int width = ae.getWidth();
+    		int height = ae.getHeight();
+    		for (int rrIx=0; rrIx<height; rrIx++) {
+    			for (int rcIx=0; rcIx<width; rcIx++) {
+    				ValueEval ve1 = ae.getRelativeValue(rrIx, rcIx);
+                     /*
+                     * TODO: For an AreaEval, we are constructing a RefEval
+                     * per element.
+                     * For now this is a tempfix solution since this may
+                     * require a more generic fix at the level of
+                     * HSSFFormulaEvaluator where we store an array
+                     * of RefEvals as the "values" array. 
+                     */
+                    RefEval re = new Ref2DEval(null, ve1);
+                    ValueEval ve = singleOperandEvaluate(re, srcRow, srcCol);
+                    
+                    if (ve instanceof NumericValueEval) {
+                        NumericValueEval nve = (NumericValueEval) ve;
+                        retval.add(nve.getNumberValue());
+                    }
+                    else if (ve instanceof BlankEval) {
+                        // note - blanks are ignored, so returned array will be smaller.
+                    } 
+                    else {
+                        return null; // indicate to calling subclass that error occurred
+                    }
+    			}
             }
             return retval.toArray();
         }
diff --git a/src/java/org/apache/poi/hssf/record/formula/functions/Offset.java b/src/java/org/apache/poi/hssf/record/formula/functions/Offset.java
index 08bdf3d64c..086596ae21 100644
--- a/src/java/org/apache/poi/hssf/record/formula/functions/Offset.java
+++ b/src/java/org/apache/poi/hssf/record/formula/functions/Offset.java
@@ -1,26 +1,22 @@
-/*
-* Licensed to the Apache Software Foundation (ASF) under one or more
-* contributor license agreements.  See the NOTICE file distributed with
-* this work for additional information regarding copyright ownership.
-* The ASF licenses this file to You under the Apache License, Version 2.0
-* (the "License"); you may not use this file except in compliance with
-* the License.  You may obtain a copy of the License at
-*
-*     http://www.apache.org/licenses/LICENSE-2.0
-*
-* Unless required by applicable law or agreed to in writing, software
-* distributed under the License is distributed on an "AS IS" BASIS,
-* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-* See the License for the specific language governing permissions and
-* limitations under the License.
-*/
+/* ====================================================================
+   Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF licenses this file to You under the Apache License, Version 2.0
+   (the "License"); you may not use this file except in compliance with
+   the License.  You may obtain a copy of the License at
 
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+==================================================================== */
 
 package org.apache.poi.hssf.record.formula.functions;
 
-import org.apache.poi.hssf.record.formula.Area3DPtg;
-import org.apache.poi.hssf.record.formula.AreaPtg;
-import org.apache.poi.hssf.record.formula.eval.Area3DEval;
 import org.apache.poi.hssf.record.formula.eval.AreaEval;
 import org.apache.poi.hssf.record.formula.eval.BoolEval;
 import org.apache.poi.hssf.record.formula.eval.ErrorEval;
@@ -28,13 +24,9 @@ import org.apache.poi.hssf.record.formula.eval.Eval;
 import org.apache.poi.hssf.record.formula.eval.EvaluationException;
 import org.apache.poi.hssf.record.formula.eval.NumericValueEval;
 import org.apache.poi.hssf.record.formula.eval.OperandResolver;
-import org.apache.poi.hssf.record.formula.eval.Ref3DEval;
 import org.apache.poi.hssf.record.formula.eval.RefEval;
 import org.apache.poi.hssf.record.formula.eval.StringEval;
 import org.apache.poi.hssf.record.formula.eval.ValueEval;
-import org.apache.poi.hssf.usermodel.HSSFFormulaEvaluator;
-import org.apache.poi.ss.usermodel.Sheet;
-import org.apache.poi.ss.usermodel.Workbook;
 /**
  * Implementation for Excel function OFFSET()<p/>
  * 
@@ -51,7 +43,7 @@ import org.apache.poi.ss.usermodel.Workbook;
  * 
  * @author Josh Micich
  */
-public final class Offset implements FreeRefFunction {
+public final class Offset implements Function {
 	// These values are specific to BIFF8
 	private static final int LAST_VALID_ROW_INDEX = 0xFFFF;
 	private static final int LAST_VALID_COLUMN_INDEX = 0xFF;
@@ -125,37 +117,29 @@ public final class Offset implements FreeRefFunction {
 	 * Encapsulates either an area or cell reference which may be 2d or 3d.
 	 */
 	private static final class BaseRef {
-		private static final int INVALID_SHEET_INDEX = -1;
 		private final int _firstRowIndex;
 		private final int _firstColumnIndex;
 		private final int _width;
 		private final int _height;
-		private final int _externalSheetIndex;
+		private final RefEval _refEval;
+		private final AreaEval _areaEval;
 		
 		public BaseRef(RefEval re) {
+			_refEval = re;
+			_areaEval = null;
 			_firstRowIndex = re.getRow();
 			_firstColumnIndex = re.getColumn();
 			_height = 1;
 			_width = 1;
-			if (re instanceof Ref3DEval) {
-				Ref3DEval r3e = (Ref3DEval) re;
-				_externalSheetIndex = r3e.getExternSheetIndex();
-			} else {
-				_externalSheetIndex = INVALID_SHEET_INDEX;
-			}
 		}
 
 		public BaseRef(AreaEval ae) {
+			_refEval = null;
+			_areaEval = ae;
 			_firstRowIndex = ae.getFirstRow();
 			_firstColumnIndex = ae.getFirstColumn();
 			_height = ae.getLastRow() - ae.getFirstRow() + 1;
 			_width = ae.getLastColumn() - ae.getFirstColumn() + 1;
-			if (ae instanceof Area3DEval) {
-				Area3DEval a3e = (Area3DEval) ae;
-				_externalSheetIndex = a3e.getExternSheetIndex();
-			} else {
-				_externalSheetIndex = INVALID_SHEET_INDEX;
-			}
 		}
 
 		public int getWidth() {
@@ -170,20 +154,17 @@ public final class Offset implements FreeRefFunction {
 		public int getFirstColumnIndex() {
 			return _firstColumnIndex;
 		}
-		public boolean isIs3d() {
-			return _externalSheetIndex > 0;
-		}
 
-		public short getExternalSheetIndex() {
-			if(_externalSheetIndex < 0) {
-				throw new IllegalStateException("external sheet index only available for 3d refs");
+		public AreaEval offset(int relFirstRowIx, int relLastRowIx, 
+				int relFirstColIx, int relLastColIx) {
+			if (_refEval == null) {
+				return _areaEval.offset(relFirstRowIx, relLastRowIx, relFirstColIx, relLastColIx);
 			}
-			return (short) _externalSheetIndex;
+			return _refEval.offset(relFirstRowIx, relLastRowIx, relFirstColIx, relLastColIx);
 		}
 	}
 	
-	public ValueEval evaluate(Eval[] args, int srcCellRow, short srcCellCol, Workbook workbook, Sheet sheet) {
-		
+	public Eval evaluate(Eval[] args, int srcCellRow, short srcCellCol) {
 		if(args.length < 3 || args.length > 5) {
 			return ErrorEval.VALUE_INVALID;
 		}
@@ -206,37 +187,24 @@ public final class Offset implements FreeRefFunction {
 			}
 			LinearOffsetRange rowOffsetRange = new LinearOffsetRange(rowOffset, height);
 			LinearOffsetRange colOffsetRange = new LinearOffsetRange(columnOffset, width);
-			return createOffset(baseRef, rowOffsetRange, colOffsetRange, workbook, sheet);
+			return createOffset(baseRef, rowOffsetRange, colOffsetRange);
 		} catch (EvaluationException e) {
 			return e.getErrorEval();
 		}
 	}
 
 	private static AreaEval createOffset(BaseRef baseRef, 
-			LinearOffsetRange rowOffsetRange, LinearOffsetRange colOffsetRange, 
-			Workbook workbook, Sheet sheet) throws EvaluationException {
-
-		LinearOffsetRange rows = rowOffsetRange.normaliseAndTranslate(baseRef.getFirstRowIndex());
-		LinearOffsetRange cols = colOffsetRange.normaliseAndTranslate(baseRef.getFirstColumnIndex());
+			LinearOffsetRange orRow, LinearOffsetRange orCol) throws EvaluationException {
+		LinearOffsetRange absRows = orRow.normaliseAndTranslate(baseRef.getFirstRowIndex());
+		LinearOffsetRange absCols = orCol.normaliseAndTranslate(baseRef.getFirstColumnIndex());
 		
-		if(rows.isOutOfBounds(0, LAST_VALID_ROW_INDEX)) {
+		if(absRows.isOutOfBounds(0, LAST_VALID_ROW_INDEX)) {
 			throw new EvaluationException(ErrorEval.REF_INVALID);
 		}
-		if(cols.isOutOfBounds(0, LAST_VALID_COLUMN_INDEX)) {
+		if(absCols.isOutOfBounds(0, LAST_VALID_COLUMN_INDEX)) {
 			throw new EvaluationException(ErrorEval.REF_INVALID);
 		}
-		if(baseRef.isIs3d()) {
-			Area3DPtg a3dp = new Area3DPtg(rows.getFirstIndex(), rows.getLastIndex(), 
-					cols.getFirstIndex(), cols.getLastIndex(),
-					false, false, false, false,
-					baseRef.getExternalSheetIndex());
-			return HSSFFormulaEvaluator.evaluateArea3dPtg(workbook, a3dp);
-		}
-		
-		AreaPtg ap = new AreaPtg(rows.getFirstIndex(), rows.getLastIndex(), 
-				cols.getFirstIndex(), cols.getLastIndex(),
-				false, false, false, false);
-		return HSSFFormulaEvaluator.evaluateAreaPtg(sheet, workbook, ap);
+		return baseRef.offset(orRow.getFirstIndex(), orRow.getLastIndex(), orCol.getFirstIndex(), orCol.getLastIndex());
 	}
 
 	private static BaseRef evaluateBaseRef(Eval eval) throws EvaluationException {
diff --git a/src/java/org/apache/poi/hssf/record/formula/functions/Sumx2my2.java b/src/java/org/apache/poi/hssf/record/formula/functions/Sumx2my2.java
index 30ad5ec230..4dedf26574 100644
--- a/src/java/org/apache/poi/hssf/record/formula/functions/Sumx2my2.java
+++ b/src/java/org/apache/poi/hssf/record/formula/functions/Sumx2my2.java
@@ -1,22 +1,23 @@
-/*
-* Licensed to the Apache Software Foundation (ASF) under one or more
-* contributor license agreements.  See the NOTICE file distributed with
-* this work for additional information regarding copyright ownership.
-* The ASF licenses this file to You under the Apache License, Version 2.0
-* (the "License"); you may not use this file except in compliance with
-* the License.  You may obtain a copy of the License at
-*
-*     http://www.apache.org/licenses/LICENSE-2.0
-*
-* Unless required by applicable law or agreed to in writing, software
-* distributed under the License is distributed on an "AS IS" BASIS,
-* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-* See the License for the specific language governing permissions and
-* limitations under the License.
-*/
+/* ====================================================================
+   Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF licenses this file to You under the Apache License, Version 2.0
+   (the "License"); you may not use this file except in compliance with
+   the License.  You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+==================================================================== */
 
 package org.apache.poi.hssf.record.formula.functions;
 
+
 /**
  * Implementation of Excel function SUMX2MY2()<p/>
  * 
@@ -30,7 +31,13 @@ package org.apache.poi.hssf.record.formula.functions;
  */
 public final class Sumx2my2 extends XYNumericFunction {
 
-    protected double evaluate(double[] xArray, double[] yArray) {
-    	return MathX.sumx2my2(xArray, yArray);
-    }
+	private static final Accumulator XSquaredMinusYSquaredAccumulator = new Accumulator() {
+		public double accumulate(double x, double y) {
+			return x * x - y * y;
+		}
+	};
+
+	protected Accumulator createAccumulator() {
+		return XSquaredMinusYSquaredAccumulator;
+	}
 }
diff --git a/src/java/org/apache/poi/hssf/record/formula/functions/Sumx2py2.java b/src/java/org/apache/poi/hssf/record/formula/functions/Sumx2py2.java
index dfd730d12c..c3af0bd380 100644
--- a/src/java/org/apache/poi/hssf/record/formula/functions/Sumx2py2.java
+++ b/src/java/org/apache/poi/hssf/record/formula/functions/Sumx2py2.java
@@ -1,22 +1,23 @@
-/*
-* Licensed to the Apache Software Foundation (ASF) under one or more
-* contributor license agreements.  See the NOTICE file distributed with
-* this work for additional information regarding copyright ownership.
-* The ASF licenses this file to You under the Apache License, Version 2.0
-* (the "License"); you may not use this file except in compliance with
-* the License.  You may obtain a copy of the License at
-*
-*     http://www.apache.org/licenses/LICENSE-2.0
-*
-* Unless required by applicable law or agreed to in writing, software
-* distributed under the License is distributed on an "AS IS" BASIS,
-* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-* See the License for the specific language governing permissions and
-* limitations under the License.
-*/
+/* ====================================================================
+   Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF licenses this file to You under the Apache License, Version 2.0
+   (the "License"); you may not use this file except in compliance with
+   the License.  You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+==================================================================== */
 
 package org.apache.poi.hssf.record.formula.functions;
 
+
 /**
  * Implementation of Excel function SUMX2PY2()<p/>
  * 
@@ -30,7 +31,13 @@ package org.apache.poi.hssf.record.formula.functions;
  */
 public final class Sumx2py2 extends XYNumericFunction {
 
-    protected double evaluate(double[] xArray, double[] yArray) {
-    	return MathX.sumx2py2(xArray, yArray);
-    }
+	private static final Accumulator XSquaredPlusYSquaredAccumulator = new Accumulator() {
+		public double accumulate(double x, double y) {
+			return x * x + y * y;
+		}
+	};
+
+	protected Accumulator createAccumulator() {
+		return XSquaredPlusYSquaredAccumulator;
+	}
 }
diff --git a/src/java/org/apache/poi/hssf/record/formula/functions/Sumxmy2.java b/src/java/org/apache/poi/hssf/record/formula/functions/Sumxmy2.java
index a1b2fec9b2..4fa11e36ba 100644
--- a/src/java/org/apache/poi/hssf/record/formula/functions/Sumxmy2.java
+++ b/src/java/org/apache/poi/hssf/record/formula/functions/Sumxmy2.java
@@ -1,19 +1,19 @@
-/*
-* Licensed to the Apache Software Foundation (ASF) under one or more
-* contributor license agreements.  See the NOTICE file distributed with
-* this work for additional information regarding copyright ownership.
-* The ASF licenses this file to You under the Apache License, Version 2.0
-* (the "License"); you may not use this file except in compliance with
-* the License.  You may obtain a copy of the License at
-*
-*     http://www.apache.org/licenses/LICENSE-2.0
-*
-* Unless required by applicable law or agreed to in writing, software
-* distributed under the License is distributed on an "AS IS" BASIS,
-* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-* See the License for the specific language governing permissions and
-* limitations under the License.
-*/
+/* ====================================================================
+   Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF licenses this file to You under the Apache License, Version 2.0
+   (the "License"); you may not use this file except in compliance with
+   the License.  You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+==================================================================== */
 
 package org.apache.poi.hssf.record.formula.functions;
 
@@ -30,7 +30,14 @@ package org.apache.poi.hssf.record.formula.functions;
  */
 public final class Sumxmy2 extends XYNumericFunction {
 
-    protected double evaluate(double[] xArray, double[] yArray) {
-    	return MathX.sumxmy2(xArray, yArray);
-    }
+	private static final Accumulator XMinusYSquaredAccumulator = new Accumulator() {
+		public double accumulate(double x, double y) {
+			double xmy = x - y;
+			return xmy * xmy;
+		}
+	};
+
+	protected Accumulator createAccumulator() {
+		return XMinusYSquaredAccumulator;
+	}
 }
diff --git a/src/java/org/apache/poi/hssf/record/formula/functions/XYNumericFunction.java b/src/java/org/apache/poi/hssf/record/formula/functions/XYNumericFunction.java
index b989c33a26..1d83b363fd 100644
--- a/src/java/org/apache/poi/hssf/record/formula/functions/XYNumericFunction.java
+++ b/src/java/org/apache/poi/hssf/record/formula/functions/XYNumericFunction.java
@@ -1,19 +1,19 @@
-/*
-* Licensed to the Apache Software Foundation (ASF) under one or more
-* contributor license agreements.  See the NOTICE file distributed with
-* this work for additional information regarding copyright ownership.
-* The ASF licenses this file to You under the Apache License, Version 2.0
-* (the "License"); you may not use this file except in compliance with
-* the License.  You may obtain a copy of the License at
-*
-*     http://www.apache.org/licenses/LICENSE-2.0
-*
-* Unless required by applicable law or agreed to in writing, software
-* distributed under the License is distributed on an "AS IS" BASIS,
-* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-* See the License for the specific language governing permissions and
-* limitations under the License.
-*/
+/* ====================================================================
+   Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF licenses this file to You under the Apache License, Version 2.0
+   (the "License"); you may not use this file except in compliance with
+   the License.  You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+==================================================================== */
 
 package org.apache.poi.hssf.record.formula.functions;
 
@@ -24,180 +24,162 @@ import org.apache.poi.hssf.record.formula.eval.EvaluationException;
 import org.apache.poi.hssf.record.formula.eval.NumberEval;
 import org.apache.poi.hssf.record.formula.eval.RefEval;
 import org.apache.poi.hssf.record.formula.eval.ValueEval;
+import org.apache.poi.hssf.record.formula.functions.LookupUtils.ValueVector;
 
 /**
  * @author Amol S. Deshmukh &lt; amolweb at ya hoo dot com &gt;
- *
+ * 
  */
 public abstract class XYNumericFunction implements Function {
-    protected static final int X = 0;
-    protected static final int Y = 1;
-    
-    protected static final class DoubleArrayPair {
 
-		private final double[] _xArray;
-		private final double[] _yArray;
+	private static abstract class ValueArray implements ValueVector {
+		private final int _size;
+		protected ValueArray(int size) {
+			_size = size;
+		}
+		public ValueEval getItem(int index) {
+			if (index < 0 || index > _size) {
+				throw new IllegalArgumentException("Specified index " + index
+						+ " is outside range (0.." + (_size - 1) + ")");
+			}
+			return getItemInternal(index);
+		}
+		protected abstract ValueEval getItemInternal(int index);
+		public final int getSize() {
+			return _size;
+		}
+	}
 
-		public DoubleArrayPair(double[] xArray, double[] yArray) {
-			_xArray = xArray;
-			_yArray = yArray;
+	private static final class SingleCellValueArray extends ValueArray {
+		private final ValueEval _value;
+		public SingleCellValueArray(ValueEval value) {
+			super(1);
+			_value = value;
 		}
-		public double[] getXArray() {
-			return _xArray;
+		protected ValueEval getItemInternal(int index) {
+			return _value;
+		}
+	}
+
+	private static final class RefValueArray extends ValueArray {
+		private final RefEval _ref;
+		public RefValueArray(RefEval ref) {
+			super(1);
+			_ref = ref;
 		}
-		public double[] getYArray() {
-			return _yArray;
+		protected ValueEval getItemInternal(int index) {
+			return _ref.getInnerValueEval();
 		}
-    }
+	}
 
+	private static final class AreaValueArray extends ValueArray {
+		private final AreaEval _ae;
+		private final int _width;
+
+		public AreaValueArray(AreaEval ae) {
+			super(ae.getWidth() * ae.getHeight());
+			_ae = ae;
+			_width = ae.getWidth();
+		}
+		protected ValueEval getItemInternal(int index) {
+			int rowIx = index / _width;
+			int colIx = index % _width;
+			return _ae.getRelativeValue(rowIx, colIx);
+		}
+	}
+
+	protected static interface Accumulator {
+		double accumulate(double x, double y);
+	}
+
+	/**
+	 * Constructs a new instance of the Accumulator used to calculated this function
+	 */
+	protected abstract Accumulator createAccumulator();
+
+	public final Eval evaluate(Eval[] args, int srcCellRow, short srcCellCol) {
+		if (args.length != 2) {
+			return ErrorEval.VALUE_INVALID;
+		}
 
-    public final Eval evaluate(Eval[] args, int srcCellRow, short srcCellCol) {
-    	if(args.length != 2) {
-    		return ErrorEval.VALUE_INVALID;
-    	}
-    	
-        double[][] values;
+		double result;
 		try {
-			values = getValues(args[0], args[1]);
+			ValueVector vvX = createValueVector(args[0]);
+			ValueVector vvY = createValueVector(args[1]);
+			int size = vvX.getSize();
+			if (size == 0 || vvY.getSize() != size) {
+				return ErrorEval.NA;
+			}
+			result = evaluateInternal(vvX, vvY, size);
 		} catch (EvaluationException e) {
 			return e.getErrorEval();
 		}
-        if (values==null 
-                || values[X] == null || values[Y] == null
-                || values[X].length == 0 || values[Y].length == 0
-                || values[X].length != values[Y].length) {
-            return ErrorEval.VALUE_INVALID;
-        }
-        
-        double d = evaluate(values[X], values[Y]);
-        if (Double.isNaN(d) || Double.isInfinite(d)) {
+		if (Double.isNaN(result) || Double.isInfinite(result)) {
 			return ErrorEval.NUM_ERROR;
 		}
-		return new NumberEval(d);
-    }    
-    protected abstract double evaluate(double[] xArray, double[] yArray);
-
-    /**
-     * Returns a double array that contains values for the numeric cells
-     * from among the list of operands. Blanks and Blank equivalent cells
-     * are ignored. Error operands or cells containing operands of type
-     * that are considered invalid and would result in #VALUE! error in 
-     * excel cause this function to return null.
-     */
-    private static double[][] getNumberArray(Eval[] xops, Eval[] yops) throws EvaluationException {
-    	
-    	// check for errors first: size mismatch, value errors in x, value errors in y
-    	
-    	int nArrayItems = xops.length;
-		if(nArrayItems != yops.length) {
-    		throw new EvaluationException(ErrorEval.NA);
-    	}
-		for (int i = 0; i < xops.length; i++) {
-			Eval eval = xops[i];
-			if (eval instanceof ErrorEval) {
-				throw new EvaluationException((ErrorEval) eval);
+		return new NumberEval(result);
+	}
+
+	private double evaluateInternal(ValueVector x, ValueVector y, int size)
+			throws EvaluationException {
+		Accumulator acc = createAccumulator();
+
+		// error handling is as if the x is fully evaluated before y
+		ErrorEval firstXerr = null;
+		ErrorEval firstYerr = null;
+		boolean accumlatedSome = false;
+		double result = 0.0;
+
+		for (int i = 0; i < size; i++) {
+			ValueEval vx = x.getItem(i);
+			ValueEval vy = y.getItem(i);
+			if (vx instanceof ErrorEval) {
+				if (firstXerr == null) {
+					firstXerr = (ErrorEval) vx;
+					continue;
+				}
 			}
-		}
-		for (int i = 0; i < yops.length; i++) {
-			Eval eval = yops[i];
-			if (eval instanceof ErrorEval) {
-				throw new EvaluationException((ErrorEval) eval);
+			if (vy instanceof ErrorEval) {
+				if (firstYerr == null) {
+					firstYerr = (ErrorEval) vy;
+					continue;
+				}
+			}
+			// only count pairs if both elements are numbers
+			if (vx instanceof NumberEval && vy instanceof NumberEval) {
+				accumlatedSome = true;
+				NumberEval nx = (NumberEval) vx;
+				NumberEval ny = (NumberEval) vy;
+				result += acc.accumulate(nx.getNumberValue(), ny.getNumberValue());
+			} else {
+				// all other combinations of value types are silently ignored
 			}
 		}
-		
-        double[] xResult = new double[nArrayItems];
-        double[] yResult = new double[nArrayItems];
-    	
-        int count = 0;
-        
-		for (int i=0, iSize=nArrayItems; i<iSize; i++) {
-		    Eval xEval = xops[i];
-		    Eval yEval = yops[i];
-		    
-		    if (isNumberEval(xEval) && isNumberEval(yEval)) {
-		    	xResult[count] = getDoubleValue(xEval);
-		    	yResult[count] = getDoubleValue(yEval);
-		        if (Double.isNaN(xResult[count]) || Double.isNaN(xResult[count])) {
-		            throw new EvaluationException(ErrorEval.NUM_ERROR);
-		        }
-		        count++;
-		    }
-		}
-        
-		return new double[][] {
-        	trimToSize(xResult, count),
-            trimToSize(yResult, count),
-		};
-    }
-    
-    private static double[][] getValues(Eval argX, Eval argY) throws EvaluationException {
-    	
-    	if (argX instanceof ErrorEval) {
-			throw new EvaluationException((ErrorEval) argX);
-		}
-    	if (argY instanceof ErrorEval) {
-			throw new EvaluationException((ErrorEval) argY);
-		}
-    	
-        Eval[] xEvals;
-		Eval[] yEvals;
-		if (argX instanceof AreaEval) {
-		    AreaEval ae = (AreaEval) argX;
-		    xEvals = ae.getValues();
-		} else {
-		    xEvals = new Eval[] { argX, };
-		}
-		
-		if (argY instanceof AreaEval) {
-		    AreaEval ae = (AreaEval) argY;
-		    yEvals = ae.getValues();
-		} else {
-		    yEvals = new Eval[] { argY, };
-		}
-		
-		return getNumberArray(xEvals, yEvals);
-    }
-    
-    private static double[] trimToSize(double[] arr, int len) {
-        double[] tarr = arr;
-        if (arr.length > len) {
-            tarr = new double[len];
-            System.arraycopy(arr, 0, tarr, 0, len);
-        }
-        return tarr;
-    }
-    
-    private static boolean isNumberEval(Eval eval) {
-        boolean retval = false;
-        
-        if (eval instanceof NumberEval) {
-            retval = true;
-        }
-        else if (eval instanceof RefEval) {
-            RefEval re = (RefEval) eval;
-            ValueEval ve = re.getInnerValueEval();
-            retval = (ve instanceof NumberEval);
-        }
-        
-        return retval;
-    }
-    
-    private static double getDoubleValue(Eval eval) {
-        double retval = 0;
-        if (eval instanceof NumberEval) {
-            NumberEval ne = (NumberEval) eval;
-            retval = ne.getNumberValue();
-        }
-        else if (eval instanceof RefEval) {
-            RefEval re = (RefEval) eval;
-            ValueEval ve = re.getInnerValueEval();
-                retval = (ve instanceof NumberEval)
-                    ? ((NumberEval) ve).getNumberValue()
-                    : Double.NaN;
-        }
-        else if (eval instanceof ErrorEval) {
-            retval = Double.NaN;
-        }
-        return retval;
-    }
+		if (firstXerr != null) {
+			throw new EvaluationException(firstXerr);
+		}
+		if (firstYerr != null) {
+			throw new EvaluationException(firstYerr);
+		}
+		if (!accumlatedSome) {
+			throw new EvaluationException(ErrorEval.DIV_ZERO);
+		}
+		return result;
+	}
+
+	private static ValueVector createValueVector(Eval arg) throws EvaluationException {
+		if (arg instanceof ErrorEval) {
+			throw new EvaluationException((ErrorEval) arg);
+		}
+		if (arg instanceof AreaEval) {
+			return new AreaValueArray((AreaEval) arg);
+		}
+		if (arg instanceof RefEval) {
+			return new RefValueArray((RefEval) arg);
+		}
+		if (arg instanceof ValueEval) {
+			return new SingleCellValueArray((ValueEval) arg);
+		}
+		throw new RuntimeException("Unexpected eval class (" + arg.getClass().getName() + ")");
+	}
 }
diff --git a/src/java/org/apache/poi/hssf/usermodel/HSSFFormulaEvaluator.java b/src/java/org/apache/poi/hssf/usermodel/HSSFFormulaEvaluator.java
index 97e605928d..4fb31606ea 100644
--- a/src/java/org/apache/poi/hssf/usermodel/HSSFFormulaEvaluator.java
+++ b/src/java/org/apache/poi/hssf/usermodel/HSSFFormulaEvaluator.java
@@ -43,19 +43,11 @@ public class HSSFFormulaEvaluator extends FormulaEvaluator {
         return new FormulaParser(formula, workbook);
     }
     
-
     /**
      * debug method
-     * 
-     * @param formula
-     * @param sheet
-     * @param workbook
      */
     void inspectPtgs(String formula) {
-    	HSSFWorkbook hssfWb = (HSSFWorkbook)_workbook;
-        FormulaParser fp = new FormulaParser(formula, hssfWb);
-        fp.parse();
-        Ptg[] ptgs = fp.getRPNPtg();
+        Ptg[] ptgs = FormulaParser.parse(formula, _workbook);
         System.out.println("<ptg-group>");
         for (int i = 0, iSize = ptgs.length; i < iSize; i++) {
             System.out.println("<ptg>");
diff --git a/src/java/org/apache/poi/hssf/usermodel/HSSFSheet.java b/src/java/org/apache/poi/hssf/usermodel/HSSFSheet.java
index 280284439b..6670b20414 100644
--- a/src/java/org/apache/poi/hssf/usermodel/HSSFSheet.java
+++ b/src/java/org/apache/poi/hssf/usermodel/HSSFSheet.java
@@ -35,17 +35,11 @@ import org.apache.poi.hssf.model.FormulaParser;
 import org.apache.poi.hssf.model.Sheet;
 import org.apache.poi.hssf.model.Workbook;
 import org.apache.poi.hssf.record.CellValueRecordInterface;
-import org.apache.poi.hssf.record.CFRuleRecord;
-import org.apache.poi.hssf.record.DVALRecord;
 import org.apache.poi.hssf.record.DVRecord;
-import org.apache.poi.hssf.record.EOFRecord;
 import org.apache.poi.hssf.record.EscherAggregate;
-import org.apache.poi.hssf.record.HCenterRecord;
-import org.apache.poi.hssf.record.PageBreakRecord;
 import org.apache.poi.hssf.record.Record;
 import org.apache.poi.hssf.record.RowRecord;
 import org.apache.poi.hssf.record.SCLRecord;
-import org.apache.poi.hssf.record.VCenterRecord;
 import org.apache.poi.hssf.record.WSBoolRecord;
 import org.apache.poi.hssf.record.WindowTwoRecord;
 import org.apache.poi.hssf.record.aggregates.DataValidityTable;
@@ -385,6 +379,22 @@ public class HSSFSheet implements org.apache.poi.ss.usermodel.Sheet
        DVRecord dvRecord = dataValidation.createDVRecord(workbook);
        dvt.addDataValidation(dvRecord);
     }
+    
+    /**
+     * Get the DVRecords objects that are associated to this sheet
+     * @return a list of DVRecord instances
+     */
+    public List getDVRecords() {
+        List dvRecords = new ArrayList();
+        List records = sheet.getRecords();
+        
+        for(int index=0; index<records.size(); index++) {
+           if(records.get(index) instanceof DVRecord) {
+        	   dvRecords.add(records.get(index));
+           }
+        }
+        return dvRecords;
+    }
 
 
     /**
@@ -1273,11 +1283,9 @@ public class HSSFSheet implements org.apache.poi.ss.usermodel.Sheet
                     // Since it's a formula cell, process the
                     //  formula string, and look to see if
                     //  it contains any references
-                    FormulaParser fp = new FormulaParser(c.getCellFormula(), workbook);
-                    fp.parse();
 
                     // Look for references, and update if needed
-                    Ptg[] ptgs = fp.getRPNPtg();
+                    Ptg[] ptgs = FormulaParser.parse(c.getCellFormula(), workbook);
                     boolean changed = false;
                     for(int i=0; i<ptgs.length; i++) {
                         if(ptgs[i] instanceof RefPtg) {
@@ -1294,7 +1302,7 @@ public class HSSFSheet implements org.apache.poi.ss.usermodel.Sheet
                     //  re-create the formula string
                     if(changed) {
                         c.setCellFormula(
-                                fp.toFormulaString(ptgs)
+                             FormulaParser.toFormulaString(workbook, ptgs)
                         );
                     }
                 }
diff --git a/src/java/org/apache/poi/hssf/usermodel/HSSFWorkbook.java b/src/java/org/apache/poi/hssf/usermodel/HSSFWorkbook.java
index eb1546ade9..801b298783 100644
--- a/src/java/org/apache/poi/hssf/usermodel/HSSFWorkbook.java
+++ b/src/java/org/apache/poi/hssf/usermodel/HSSFWorkbook.java
@@ -931,35 +931,17 @@ public class HSSFWorkbook extends POIDocument implements org.apache.poi.ss.userm
         Stack ptgs = new Stack();
 
         if (settingRowAndColumn) {
-            final int exprsSize = 2 * 11 + 1; // Area3DPtg.SIZE + UnionPtg.SIZE
+            final int exprsSize = 2 * 11 + 1; // 2 * Area3DPtg.SIZE + UnionPtg.SIZE
             ptgs.add(new MemFuncPtg(exprsSize));
         }
-        if (startColumn >= 0)
-        {
-            Area3DPtg colArea = new Area3DPtg();
-            colArea.setExternSheetIndex(externSheetIndex);
-            colArea.setFirstColumn((short)startColumn);
-            colArea.setLastColumn((short)endColumn);
-            colArea.setFirstRow(0);
-            colArea.setLastRow(MAX_ROW);
-            colArea.setFirstColRelative(false);
-            colArea.setLastColRelative(false);
-            colArea.setFirstRowRelative(false);
-            colArea.setLastRowRelative(false);
+        if (startColumn >= 0) {
+            Area3DPtg colArea = new Area3DPtg(0, MAX_ROW, startColumn, endColumn, 
+                    false, false, false, false, externSheetIndex);
             ptgs.add(colArea);
         }
-        if (startRow >= 0)
-        {
-            Area3DPtg rowArea = new Area3DPtg();
-            rowArea.setExternSheetIndex(externSheetIndex);
-            rowArea.setFirstColumn((short)0);
-            rowArea.setLastColumn(MAX_COLUMN);
-            rowArea.setFirstRow(startRow);
-            rowArea.setLastRow(endRow);
-            rowArea.setFirstColRelative(false);
-            rowArea.setLastColRelative(false);
-            rowArea.setFirstRowRelative(false);
-            rowArea.setLastRowRelative(false);
+        if (startRow >= 0) {
+            Area3DPtg rowArea = new Area3DPtg(startRow, endRow, 0, MAX_COLUMN, 
+                    false, false, false, false, externSheetIndex);
             ptgs.add(rowArea);
         }
         if (settingRowAndColumn)
diff --git a/src/java/org/apache/poi/hssf/util/AreaReference.java b/src/java/org/apache/poi/hssf/util/AreaReference.java
index a10b9976aa..d6575642ee 100644
--- a/src/java/org/apache/poi/hssf/util/AreaReference.java
+++ b/src/java/org/apache/poi/hssf/util/AreaReference.java
@@ -17,293 +17,21 @@
 
 package org.apache.poi.hssf.util;
 
-import java.util.ArrayList;
-import java.util.StringTokenizer;
-
-import org.apache.poi.hssf.record.formula.AreaI;
-
-public final class AreaReference {
-
-    /** The character (!) that separates sheet names from cell references */ 
-    private static final char SHEET_NAME_DELIMITER = '!';
-    /** The character (:) that separates the two cell references in a multi-cell area reference */
-    private static final char CELL_DELIMITER = ':';
-    /** The character (') used to quote sheet names when they contain special characters */
-    private static final char SPECIAL_NAME_DELIMITER = '\'';
-    
-    private final CellReference _firstCell;
-    private final CellReference _lastCell;
-    private final boolean _isSingleCell;
 
+public final class AreaReference extends org.apache.poi.ss.util.AreaReference {
     /**
      * Create an area ref from a string representation.  Sheet names containing special characters should be
      * delimited and escaped as per normal syntax rules for formulas.<br/> 
      * The area reference must be contiguous (i.e. represent a single rectangle, not a union of rectangles)
      */
     public AreaReference(String reference) {
-        if(! isContiguous(reference)) {
-            throw new IllegalArgumentException(
-                    "References passed to the AreaReference must be contiguous, " +
-                    "use generateContiguous(ref) if you have non-contiguous references");
-        }
-
-        String[] parts = separateAreaRefs(reference);
-        
-        // Special handling for whole-column references
-        if(parts.length == 2 && parts[0].length() == 1 &&
-                parts[1].length() == 1 && 
-                parts[0].charAt(0) >= 'A' && parts[0].charAt(0) <= 'Z' &&
-                parts[1].charAt(0) >= 'A' && parts[1].charAt(0) <= 'Z') {
-            // Represented internally as x$1 to x$65536
-            //  which is the maximum range of rows
-            parts[0] = parts[0] + "$1";
-            parts[1] = parts[1] + "$65536";
-        }
-        
-        _firstCell = new CellReference(parts[0]);
-        
-        if(parts.length == 2) {
-            _lastCell = new CellReference(parts[1]);
-            _isSingleCell = false;
-        } else {
-            _lastCell = _firstCell;
-            _isSingleCell = true;
-        }
+		super(reference);
     }
     
     /**
      * Creates an area ref from a pair of Cell References.
      */
     public AreaReference(CellReference topLeft, CellReference botRight) {
-        _firstCell = topLeft;
-        _lastCell = botRight;
-        _isSingleCell = false;
-    }
-
-    /**
-     * Is the reference for a contiguous (i.e.
-     *  unbroken) area, or is it made up of
-     *  several different parts?
-     * (If it is, you will need to call
-     *  ....
-     */
-    public static boolean isContiguous(String reference) {
-        if(reference.indexOf(',') == -1) {
-            return true;
-        }
-        return false;
-    }
-    
-    /**
-     * Is the reference for a whole-column reference,
-     *  such as C:C or D:G ?
-     */
-    public static boolean isWholeColumnReference(CellReference topLeft, CellReference botRight) {
-        // These are represented as something like
-        //   C$1:C$65535 or D$1:F$0
-        // i.e. absolute from 1st row to 0th one
-        if(topLeft.getRow() == 0 && topLeft.isRowAbsolute() &&
-            botRight.getRow() == 65535 && botRight.isRowAbsolute()) {
-            return true;
-        }
-        return false;
-    }
-    public boolean isWholeColumnReference() {
-        return isWholeColumnReference(_firstCell, _lastCell);
-    }
-
-    /**
-     * Takes a non-contiguous area reference, and
-     *  returns an array of contiguous area references.
-     */
-    public static AreaReference[] generateContiguous(String reference) {
-        ArrayList refs = new ArrayList();
-        StringTokenizer st = new StringTokenizer(reference, ",");
-        while(st.hasMoreTokens()) {
-            refs.add(
-                    new AreaReference(st.nextToken())
-            );
-        }
-        return (AreaReference[])refs.toArray(new AreaReference[refs.size()]);
-    }
-
-    /**
-     * @return <code>false</code> if this area reference involves more than one cell
-     */
-    public boolean isSingleCell() {
-        return _isSingleCell;
-    }
-    
-    /**
-     * @return the first cell reference which defines this area. Usually this cell is in the upper
-     * left corner of the area (but this is not a requirement).
-     */
-   public CellReference getFirstCell() {
-        return _firstCell;
-    }
-    
-    /**
-     * Note - if this area reference refers to a single cell, the return value of this method will
-     * be identical to that of <tt>getFirstCell()</tt>
-     * @return the second cell reference which defines this area.  For multi-cell areas, this is 
-     * cell diagonally opposite the 'first cell'.  Usually this cell is in the lower right corner 
-     * of the area (but this is not a requirement).
-     */
-    public CellReference getLastCell() {
-        return _lastCell;
-    }
-    /**
-     * Returns a reference to every cell covered by this area
-     */
-    public CellReference[] getAllReferencedCells() {
-        // Special case for single cell reference
-        if(_isSingleCell) {
-            return  new CellReference[] { _firstCell, };
-        }
- 
-        // Interpolate between the two
-        int minRow = Math.min(_firstCell.getRow(), _lastCell.getRow());
-        int maxRow = Math.max(_firstCell.getRow(), _lastCell.getRow());
-        int minCol = Math.min(_firstCell.getCol(), _lastCell.getCol());
-        int maxCol = Math.max(_firstCell.getCol(), _lastCell.getCol());
-        String sheetName = _firstCell.getSheetName();
-        
-        ArrayList refs = new ArrayList();
-        for(int row=minRow; row<=maxRow; row++) {
-            for(int col=minCol; col<=maxCol; col++) {
-                CellReference ref = new CellReference(sheetName, row, col, _firstCell.isRowAbsolute(), _firstCell.isColAbsolute());
-                refs.add(ref);
-            }
-        }
-        return (CellReference[])refs.toArray(new CellReference[refs.size()]);
-    }
-
-    /**
-     *  Example return values:
-     *    <table border="0" cellpadding="1" cellspacing="0" summary="Example return values">
-     *      <tr><th align='left'>Result</th><th align='left'>Comment</th></tr>
-     *      <tr><td>A1:A1</td><td>Single cell area reference without sheet</td></tr>
-     *      <tr><td>A1:$C$1</td><td>Multi-cell area reference without sheet</td></tr>
-     *      <tr><td>Sheet1!A$1:B4</td><td>Standard sheet name</td></tr>
-     *      <tr><td>'O''Brien''s Sales'!B5:C6'&nbsp;</td><td>Sheet name with special characters</td></tr>
-     *    </table>
-     * @return the text representation of this area reference as it would appear in a formula.
-     */
-    public String formatAsString() {
-        // Special handling for whole-column references
-        if(isWholeColumnReference()) {
-            return
-                CellReference.convertNumToColString(_firstCell.getCol())
-                + ":" +
-                CellReference.convertNumToColString(_lastCell.getCol());
-        }
-        
-        StringBuffer sb = new StringBuffer(32);
-        sb.append(_firstCell.formatAsString());
-        if(!_isSingleCell) {
-            sb.append(CELL_DELIMITER);
-            if(_lastCell.getSheetName() == null) {
-                sb.append(_lastCell.formatAsString());
-            } else {
-                // don't want to include the sheet name twice
-                _lastCell.appendCellReference(sb);
-            }
-        }
-        return sb.toString();
-    }
-    /**
-     * Formats a 2-D area as it would appear in a formula.  See formatAsString() (no-arg)
-     */
-    public static String formatAsString(AreaI area) {
-        CellReference topLeft = new CellReference(area.getFirstRow(),area.getFirstColumn(),!area.isFirstRowRelative(),!area.isFirstColRelative());
-        CellReference botRight = new CellReference(area.getLastRow(),area.getLastColumn(),!area.isLastRowRelative(),!area.isLastColRelative());
-        
-        if(isWholeColumnReference(topLeft, botRight)) {
-            return (new AreaReference(topLeft, botRight)).formatAsString();
-        }
-        return topLeft.formatAsString() + ":" + botRight.formatAsString(); 
-    }
-    public String toString() {
-        StringBuffer sb = new StringBuffer(64);
-        sb.append(getClass().getName()).append(" [");
-        sb.append(formatAsString());
-        sb.append("]");
-        return sb.toString();
-    }
-
-    /**
-     * Separates Area refs in two parts and returns them as separate elements in a String array,
-     * each qualified with the sheet name (if present)
-     * 
-     * @return array with one or two elements. never <code>null</code>
-     */
-    private static String[] separateAreaRefs(String reference) {
-        // TODO - refactor cell reference parsing logic to one place.
-        // Current known incarnations: 
-        //   FormulaParser.GetName()
-        //   CellReference.separateRefParts() 
-        //   AreaReference.separateAreaRefs() (here)
-        //   SheetNameFormatter.format() (inverse)
-        
-        
-        int len = reference.length();
-        int delimiterPos = -1;
-        boolean insideDelimitedName = false;
-        for(int i=0; i<len; i++) {
-            switch(reference.charAt(i)) {
-                case CELL_DELIMITER:
-                    if(!insideDelimitedName) {
-                        if(delimiterPos >=0) {
-                            throw new IllegalArgumentException("More than one cell delimiter '" 
-                                    + CELL_DELIMITER + "' appears in area reference '" + reference + "'");
-                        }
-                        delimiterPos = i;
-                    }
-                default:
-                    continue;
-                case SPECIAL_NAME_DELIMITER:
-                    // fall through
-            }
-            if(!insideDelimitedName) {
-                insideDelimitedName = true;
-                continue;
-            }
-            
-            if(i >= len-1) {
-                // reference ends with the delimited name. 
-                // Assume names like: "Sheet1!'A1'" are never legal.
-                throw new IllegalArgumentException("Area reference '" + reference 
-                        + "' ends with special name delimiter '"  + SPECIAL_NAME_DELIMITER + "'");
-            }
-            if(reference.charAt(i+1) == SPECIAL_NAME_DELIMITER) {
-                // two consecutive quotes is the escape sequence for a single one
-                i++; // skip this and keep parsing the special name
-            } else {
-                // this is the end of the delimited name
-                insideDelimitedName = false;
-            }
-        }
-        if(delimiterPos < 0) {
-            return new String[] { reference, };
-        }
-
-        String partA = reference.substring(0, delimiterPos);
-        String partB = reference.substring(delimiterPos+1);
-        if(partB.indexOf(SHEET_NAME_DELIMITER) >=0) {
-            // TODO - are references like "Sheet1!A1:Sheet1:B2" ever valid?  
-            // FormulaParser has code to handle that.
-            
-            throw new RuntimeException("Unexpected " + SHEET_NAME_DELIMITER 
-                    + " in second cell reference of '" + reference + "'");
-        }
-        
-        int plingPos = partA.lastIndexOf(SHEET_NAME_DELIMITER);
-        if(plingPos < 0) {
-            return new String [] { partA, partB, };
-        }
-        
-        String sheetName = partA.substring(0, plingPos + 1); // +1 to include delimiter
-        
-        return new String [] { partA, sheetName + partB, };
+		super(topLeft, botRight);
     }
-}
\ No newline at end of file
+}
diff --git a/src/java/org/apache/poi/ss/usermodel/FormulaEvaluator.java b/src/java/org/apache/poi/ss/usermodel/FormulaEvaluator.java
index 74e92b0a8d..aa71c68c54 100644
--- a/src/java/org/apache/poi/ss/usermodel/FormulaEvaluator.java
+++ b/src/java/org/apache/poi/ss/usermodel/FormulaEvaluator.java
@@ -1,26 +1,23 @@
-/*
-* Licensed to the Apache Software Foundation (ASF) under one or more
-* contributor license agreements.  See the NOTICE file distributed with
-* this work for additional information regarding copyright ownership.
-* The ASF licenses this file to You under the Apache License, Version 2.0
-* (the "License"); you may not use this file except in compliance with
-* the License.  You may obtain a copy of the License at
-*
-*     http://www.apache.org/licenses/LICENSE-2.0
-*
-* Unless required by applicable law or agreed to in writing, software
-* distributed under the License is distributed on an "AS IS" BASIS,
-* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-* See the License for the specific language governing permissions and
-* limitations under the License.
-*/
+/* ====================================================================
+   Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF licenses this file to You under the Apache License, Version 2.0
+   (the "License"); you may not use this file except in compliance with
+   the License.  You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+==================================================================== */
 
 package org.apache.poi.ss.usermodel;
 
-import java.lang.reflect.Constructor;
-import java.util.HashMap;
 import java.util.Iterator;
-import java.util.Map;
 import java.util.Stack;
 
 import org.apache.poi.hssf.model.FormulaParser;
@@ -28,6 +25,7 @@ import org.apache.poi.hssf.record.formula.Area3DPtg;
 import org.apache.poi.hssf.record.formula.AreaPtg;
 import org.apache.poi.hssf.record.formula.BoolPtg;
 import org.apache.poi.hssf.record.formula.ControlPtg;
+import org.apache.poi.hssf.record.formula.ErrPtg;
 import org.apache.poi.hssf.record.formula.IntPtg;
 import org.apache.poi.hssf.record.formula.MemErrPtg;
 import org.apache.poi.hssf.record.formula.MissingArgPtg;
@@ -41,77 +39,51 @@ import org.apache.poi.hssf.record.formula.RefPtg;
 import org.apache.poi.hssf.record.formula.StringPtg;
 import org.apache.poi.hssf.record.formula.UnionPtg;
 import org.apache.poi.hssf.record.formula.UnknownPtg;
-import org.apache.poi.hssf.record.formula.eval.Area2DEval;
-import org.apache.poi.hssf.record.formula.eval.Area3DEval;
 import org.apache.poi.hssf.record.formula.eval.AreaEval;
 import org.apache.poi.hssf.record.formula.eval.BlankEval;
 import org.apache.poi.hssf.record.formula.eval.BoolEval;
 import org.apache.poi.hssf.record.formula.eval.ErrorEval;
 import org.apache.poi.hssf.record.formula.eval.Eval;
 import org.apache.poi.hssf.record.formula.eval.FunctionEval;
+import org.apache.poi.hssf.record.formula.eval.LazyAreaEval;
+import org.apache.poi.hssf.record.formula.eval.LazyRefEval;
 import org.apache.poi.hssf.record.formula.eval.NameEval;
 import org.apache.poi.hssf.record.formula.eval.NameXEval;
 import org.apache.poi.hssf.record.formula.eval.NumberEval;
 import org.apache.poi.hssf.record.formula.eval.OperationEval;
-import org.apache.poi.hssf.record.formula.eval.Ref2DEval;
-import org.apache.poi.hssf.record.formula.eval.Ref3DEval;
 import org.apache.poi.hssf.record.formula.eval.RefEval;
 import org.apache.poi.hssf.record.formula.eval.StringEval;
 import org.apache.poi.hssf.record.formula.eval.ValueEval;
-import org.apache.poi.hssf.usermodel.HSSFFormulaEvaluator;
 
 /**
  * @author Amol S. Deshmukh &lt; amolweb at ya hoo dot com &gt;
- * 
+ *
  */
 public class FormulaEvaluator {
-                
-    // params to lookup the right constructor using reflection
-    private static final Class[] VALUE_CONTRUCTOR_CLASS_ARRAY = new Class[] { Ptg.class };
 
-    private static final Class[] AREA3D_CONSTRUCTOR_CLASS_ARRAY = new Class[] { Ptg.class, ValueEval[].class };
-
-    private static final Class[] REFERENCE_CONSTRUCTOR_CLASS_ARRAY = new Class[] { Ptg.class, ValueEval.class };
-
-    private static final Class[] REF3D_CONSTRUCTOR_CLASS_ARRAY = new Class[] { Ptg.class, ValueEval.class };
-
-    // Maps for mapping *Eval to *Ptg
-    private static final Map VALUE_EVALS_MAP = new HashMap();
-
-    /*
-     * Following is the mapping between the Ptg tokens returned 
-     * by the FormulaParser and the *Eval classes that are used 
-     * by the FormulaEvaluator
-     */
-    static {
-        VALUE_EVALS_MAP.put(BoolPtg.class, BoolEval.class);
-        VALUE_EVALS_MAP.put(IntPtg.class, NumberEval.class);
-        VALUE_EVALS_MAP.put(NumberPtg.class, NumberEval.class);
-        VALUE_EVALS_MAP.put(StringPtg.class, StringEval.class);
-
-    }
-
-    
     protected Sheet _sheet;
     protected Workbook _workbook;
-    
+
     public FormulaEvaluator(Sheet sheet, Workbook workbook) {
-        this._sheet = sheet;
-        this._workbook = workbook;
+        _sheet = sheet;
+        _workbook = workbook;
     }
-    
+
     /**
      * Does nothing
      * @deprecated (Aug 2008) - not needed, since the current row can be derived from the cell
      */
-    public void setCurrentRow(Row row) {}
+    public void setCurrentRow(Row row) {
+        // do nothing
+    }
+
 
     /**
      * If cell contains a formula, the formula is evaluated and returned,
      * else the CellValue simply copies the appropriate cell value from
      * the cell and also its cell type. This method should be preferred over
      * evaluateInCell() when the call should not modify the contents of the
-     * original cell. 
+     * original cell.
      * @param cell
      */
     public CellValue evaluate(Cell cell) {
@@ -144,25 +116,25 @@ public class FormulaEvaluator {
         }
         return retval;
     }
-    
-    
+
+
     /**
      * If cell contains formula, it evaluates the formula,
      *  and saves the result of the formula. The cell
      *  remains as a formula cell.
      * Else if cell does not contain formula, this method leaves
-     *  the cell unchanged. 
+     *  the cell unchanged.
      * Note that the type of the formula result is returned,
      *  so you know what kind of value is also stored with
-     *  the formula. 
+     *  the formula.
      * <pre>
      * int evaluatedCellType = evaluator.evaluateFormulaCell(cell);
      * </pre>
      * Be aware that your cell will hold both the formula,
      *  and the result. If you want the cell replaced with
-     *  the result of the formula, use {@link #evaluateInCell(HSSFCell)}
+     *  the result of the formula, use {@link #evaluateInCell(Cell)}
      * @param cell The cell to evaluate
-     * @return The type of the formula result (the cell's type remains as HSSFCell.CELL_TYPE_FORMULA however)
+     * @return The type of the formula result (the cell's type remains as Cell.CELL_TYPE_FORMULA however)
      */
     public int evaluateFormulaCell(Cell cell) {
         if (cell != null) {
@@ -192,21 +164,21 @@ public class FormulaEvaluator {
         }
         return -1;
     }
-        
+
     /**
      * If cell contains formula, it evaluates the formula, and
      *  puts the formula result back into the cell, in place
      *  of the old formula.
      * Else if cell does not contain formula, this method leaves
-     *  the cell unchanged. 
-     * Note that the same instance of HSSFCell is returned to 
+     *  the cell unchanged.
+     * Note that the same instance of Cell is returned to
      * allow chained calls like:
      * <pre>
      * int evaluatedCellType = evaluator.evaluateInCell(cell).getCellType();
      * </pre>
      * Be aware that your cell value will be changed to hold the
      *  result of the formula. If you simply want the formula
-     *  value computed for you, use {@link #evaluateFormulaCell(HSSFCell)}
+     *  value computed for you, use {@link #evaluateFormulaCell(Cell)}
      * @param cell
      */
     public Cell evaluateInCell(Cell cell) {
@@ -239,7 +211,7 @@ public class FormulaEvaluator {
         }
         return cell;
     }
-    
+
     /**
      * Loops over all cells in all sheets of the supplied
      *  workbook.
@@ -248,32 +220,32 @@ public class FormulaEvaluator {
      *  remain as formula cells.
      * For cells that do not contain formulas, no changes
      *  are made.
-     * This is a helpful wrapper around looping over all 
+     * This is a helpful wrapper around looping over all
      *  cells, and calling evaluateFormulaCell on each one.
      */
-	public static void evaluateAllFormulaCells(Workbook wb) {
-		for(int i=0; i<wb.getNumberOfSheets(); i++) {
-			Sheet sheet = wb.getSheetAt(i);
-			FormulaEvaluator evaluator = new FormulaEvaluator(sheet, wb);
-
-			for (Iterator rit = sheet.rowIterator(); rit.hasNext();) {
-				Row r = (Row)rit.next();
-
-				for (Iterator cit = r.cellIterator(); cit.hasNext();) {
-					Cell c = (Cell)cit.next();
-					if (c.getCellType() == Cell.CELL_TYPE_FORMULA)
-						evaluator.evaluateFormulaCell(c);
-				}
-			}
-		}
-	}
-        
-    
+    public static void evaluateAllFormulaCells(Workbook wb) {
+        for(int i=0; i<wb.getNumberOfSheets(); i++) {
+            Sheet sheet = wb.getSheetAt(i);
+            FormulaEvaluator evaluator = new FormulaEvaluator(sheet, wb);
+
+            for (Iterator rit = sheet.rowIterator(); rit.hasNext();) {
+                Row r = (Row)rit.next();
+
+                for (Iterator cit = r.cellIterator(); cit.hasNext();) {
+                    Cell c = (Cell)cit.next();
+                    if (c.getCellType() == Cell.CELL_TYPE_FORMULA)
+                        evaluator.evaluateFormulaCell(c);
+                }
+            }
+        }
+    }
+
+
     /**
      * Returns a CellValue wrapper around the supplied ValueEval instance.
      * @param eval
      */
-    protected static CellValue getCellValueForEval(ValueEval eval, CreationHelper cHelper) {
+    private static CellValue getCellValueForEval(ValueEval eval, CreationHelper cHelper) {
         CellValue retval = null;
         if (eval != null) {
             if (eval instanceof NumberEval) {
@@ -297,7 +269,7 @@ public class FormulaEvaluator {
             else if (eval instanceof ErrorEval) {
                 retval = new CellValue(Cell.CELL_TYPE_ERROR, cHelper);
                 retval.setErrorValue((byte)((ErrorEval)eval).getErrorCode());
-//                retval.setRichTextStringValue(new HSSFRichTextString("#An error occurred. check cell.getErrorCode()"));
+//                retval.setRichTextStringValue(new RichTextString("#An error occurred. check cell.getErrorCode()"));
             }
             else {
                 retval = new CellValue(Cell.CELL_TYPE_ERROR, cHelper);
@@ -305,19 +277,19 @@ public class FormulaEvaluator {
         }
         return retval;
     }
-    
+
     /**
-     * Dev. Note: Internal evaluate must be passed only a formula cell 
+     * Dev. Note: Internal evaluate must be passed only a formula cell
      * else a runtime exception will be thrown somewhere inside the method.
      * (Hence this is a private method.)
      */
     private static ValueEval internalEvaluate(Cell srcCell, Sheet sheet, Workbook workbook) {
         int srcRowNum = srcCell.getRowIndex();
         short srcColNum = srcCell.getCellNum();
-        
-        
+
+
         EvaluationCycleDetector tracker = EvaluationCycleDetectorManager.getTracker();
-        
+
         if(!tracker.startEvaluate(workbook, sheet, srcRowNum, srcColNum)) {
             return ErrorEval.CIRCULAR_REF_ERROR;
         }
@@ -327,8 +299,9 @@ public class FormulaEvaluator {
             tracker.endEvaluate(workbook, sheet, srcRowNum, srcColNum);
         }
     }
-    private static ValueEval evaluateCell(Workbook workbook, Sheet sheet, 
+    private static ValueEval evaluateCell(Workbook workbook, Sheet sheet,
             int srcRowNum, short srcColNum, String cellFormulaText) {
+
         Ptg[] ptgs = FormulaParser.parse(cellFormulaText, workbook);
 
         Stack stack = new Stack();
@@ -337,16 +310,16 @@ public class FormulaEvaluator {
             // since we don't know how to handle these yet :(
             Ptg ptg = ptgs[i];
             if (ptg instanceof ControlPtg) {
-               // skip Parentheses, Attr, etc
-               continue;
-			}
+                // skip Parentheses, Attr, etc
+                continue;
+            }
             if (ptg instanceof MemErrPtg) { continue; }
             if (ptg instanceof MissingArgPtg) { continue; }
-            if (ptg instanceof NamePtg) { 
+            if (ptg instanceof NamePtg) {
                 // named ranges, macro functions
                 NamePtg namePtg = (NamePtg) ptg;
                 stack.push(new NameEval(namePtg.getIndex()));
-                continue; 
+                continue;
             }
             if (ptg instanceof NameXPtg) {
                 NameXPtg nameXPtg = (NameXPtg) ptg;
@@ -354,7 +327,7 @@ public class FormulaEvaluator {
                 continue;
             }
             if (ptg instanceof UnknownPtg) { continue; }
-
+            Eval opResult;
             if (ptg instanceof OperationPtg) {
                 OperationPtg optg = (OperationPtg) ptg;
 
@@ -370,42 +343,11 @@ public class FormulaEvaluator {
                     Eval p = (Eval) stack.pop();
                     ops[j] = p;
                 }
-                Eval opresult = invokeOperation(operation, ops, srcRowNum, srcColNum, workbook, sheet);
-                stack.push(opresult);
-            }
-            else if (ptg instanceof RefPtg) {
-                RefPtg refPtg = (RefPtg) ptg;
-                int colIx = refPtg.getColumn();
-                int rowIx = refPtg.getRow();
-                Row row = sheet.getRow(rowIx);
-                Cell cell = (row != null) ? row.getCell(colIx) : null;
-                stack.push(createRef2DEval(refPtg, cell, sheet, workbook));
-            }
-            else if (ptg instanceof Ref3DPtg) {
-                Ref3DPtg refPtg = (Ref3DPtg) ptg;
-                int colIx = refPtg.getColumn();
-                int rowIx = refPtg.getRow();
-                Sheet xsheet = workbook.getSheetAt(
-                		workbook.getSheetIndexFromExternSheetIndex(refPtg.getExternSheetIndex())
-                );
-                Row row = xsheet.getRow(rowIx);
-                Cell cell = (row != null) ? row.getCell(colIx) : null;
-                stack.push(createRef3DEval(refPtg, cell, xsheet, workbook));
-            }
-            else if (ptg instanceof AreaPtg) {
-                AreaPtg ap = (AreaPtg) ptg;
-                AreaEval ae = evaluateAreaPtg(sheet, workbook, ap);
-                stack.push(ae);
-            }
-            else if (ptg instanceof Area3DPtg) {
-                Area3DPtg a3dp = (Area3DPtg) ptg;
-                AreaEval ae = evaluateArea3dPtg(workbook, a3dp);
-                stack.push(ae);
-            }
-            else {
-                Eval ptgEval = getEvalForPtg(ptg);
-                stack.push(ptgEval);
+                opResult = invokeOperation(operation, ops, srcRowNum, srcColNum, workbook, sheet);
+            } else {
+                opResult = getEvalForPtg(ptg, sheet, workbook);
             }
+            stack.push(opResult);
         }
 
         ValueEval value = ((ValueEval) stack.pop());
@@ -414,9 +356,9 @@ public class FormulaEvaluator {
         }
         value = dereferenceValue(value, srcRowNum, srcColNum);
         if (value instanceof BlankEval) {
-        	// Note Excel behaviour here. A blank final final value is converted to zero.  
+            // Note Excel behaviour here. A blank final final value is converted to zero.
             return NumberEval.ZERO;
-            // Formulas _never_ evaluate to blank.  If a formula appears to have evaluated to 
+            // Formulas _never_ evaluate to blank.  If a formula appears to have evaluated to
             // blank, the actual value is empty string. This can be verified with ISBLANK().
         }
         return value;
@@ -425,8 +367,8 @@ public class FormulaEvaluator {
     /**
      * Dereferences a single value from any AreaEval or RefEval evaluation result.
      * If the supplied evaluationResult is just a plain value, it is returned as-is.
-	 * @return a <tt>NumberEval</tt>, <tt>StringEval</tt>, <tt>BoolEval</tt>,
-	 *  <tt>BlankEval</tt> or <tt>ErrorEval</tt>. Never <code>null</code>.
+     * @return a <tt>NumberEval</tt>, <tt>StringEval</tt>, <tt>BoolEval</tt>,
+     *  <tt>BlankEval</tt> or <tt>ErrorEval</tt>. Never <code>null</code>.
      */
     private static ValueEval dereferenceValue(ValueEval evaluationResult, int srcRowNum, short srcColNum) {
         if (evaluationResult instanceof RefEval) {
@@ -460,107 +402,48 @@ public class FormulaEvaluator {
         }
         return operation.evaluate(ops, srcRowNum, srcColNum);
     }
-    
-    public static AreaEval evaluateAreaPtg(Sheet sheet, Workbook workbook, AreaPtg ap) {
-        int row0 = ap.getFirstRow();
-        int col0 = ap.getFirstColumn();
-        int row1 = ap.getLastRow();
-        int col1 = ap.getLastColumn();
-        
-        // If the last row is -1, then the
-        //  reference is for the rest of the column
-        // (eg C:C)
-        // TODO: Handle whole column ranges properly
-        if(row1 == -1 && row0 >= 0) {
-            row1 = (short)sheet.getLastRowNum();
-        }
-        ValueEval[] values = evalArea(workbook, sheet, row0, col0, row1, col1);
-        return new Area2DEval(ap, values);
-    }
-
-    public static AreaEval evaluateArea3dPtg(Workbook workbook, Area3DPtg a3dp) {
-    	int row0 = a3dp.getFirstRow();
-    	int col0 = a3dp.getFirstColumn();
-    	int row1 = a3dp.getLastRow();
-    	int col1 = a3dp.getLastColumn();
-        Sheet xsheet = workbook.getSheetAt(
-        		workbook.getSheetIndexFromExternSheetIndex(a3dp.getExternSheetIndex())
-        );
-        
-        // If the last row is -1, then the
-        //  reference is for the rest of the column
-        // (eg C:C)
-        // TODO: Handle whole column ranges properly
-        if(row1 == -1 && row0 >= 0) {
-            row1 = (short)xsheet.getLastRowNum();
-        }
-        
-        ValueEval[] values = evalArea(workbook, xsheet, row0, col0, row1, col1);
-        return new Area3DEval(a3dp, values);
-    }
-    
-    private static ValueEval[] evalArea(Workbook workbook, Sheet sheet, 
-    		int row0, int col0, int row1, int col1) {
-        ValueEval[] values = new ValueEval[(row1 - row0 + 1) * (col1 - col0 + 1)];
-        for (int x = row0; sheet != null && x < row1 + 1; x++) {
-            Row row = sheet.getRow(x);
-            for (int y = col0; y < col1 + 1; y++) {
-                ValueEval cellEval;
-                if(row == null) {
-                	cellEval = BlankEval.INSTANCE;
-                } else {
-                	cellEval = getEvalForCell(row.getCell(y), row, sheet, workbook);
-                }
-				values[(x - row0) * (col1 - col0 + 1) + (y - col0)] = cellEval;
-            }
-        }
-        return values;
-    }
 
     /**
      * returns an appropriate Eval impl instance for the Ptg. The Ptg must be
-     * one of: Area3DPtg, AreaPtg, RefPtg, Ref3DPtg, IntPtg, NumberPtg,
+     * one of: Area3DPtg, AreaPtg, ReferencePtg, Ref3DPtg, IntPtg, NumberPtg,
      * StringPtg, BoolPtg <br/>special Note: OperationPtg subtypes cannot be
      * passed here!
-     * 
-     * @param ptg
      */
-    protected static Eval getEvalForPtg(Ptg ptg) {
-        Eval retval = null;
-
-        Class clazz = (Class) VALUE_EVALS_MAP.get(ptg.getClass());
-        try {
-            if (ptg instanceof Area3DPtg) {
-                Constructor constructor = clazz.getConstructor(AREA3D_CONSTRUCTOR_CLASS_ARRAY);
-                retval = (OperationEval) constructor.newInstance(new Ptg[] { ptg });
-            }
-            else if (ptg instanceof AreaPtg) {
-                Constructor constructor = clazz.getConstructor(AREA3D_CONSTRUCTOR_CLASS_ARRAY);
-                retval = (OperationEval) constructor.newInstance(new Ptg[] { ptg });
-            }
-            else if (ptg instanceof RefPtg) {
-                Constructor constructor = clazz.getConstructor(REFERENCE_CONSTRUCTOR_CLASS_ARRAY);
-                retval = (OperationEval) constructor.newInstance(new Ptg[] { ptg });
-            }
-            else if (ptg instanceof Ref3DPtg) {
-                Constructor constructor = clazz.getConstructor(REF3D_CONSTRUCTOR_CLASS_ARRAY);
-                retval = (OperationEval) constructor.newInstance(new Ptg[] { ptg });
-            }
-            else {
-                if (ptg instanceof IntPtg || ptg instanceof NumberPtg || ptg instanceof StringPtg
-                        || ptg instanceof BoolPtg) {
-                    Constructor constructor = clazz.getConstructor(VALUE_CONTRUCTOR_CLASS_ARRAY);
-                    retval = (ValueEval) constructor.newInstance(new Ptg[] { ptg });
-                }
-            }
+    private static Eval getEvalForPtg(Ptg ptg, Sheet sheet, Workbook workbook) {
+        if (ptg instanceof RefPtg) {
+            return new LazyRefEval(((RefPtg) ptg), sheet, workbook);
         }
-        catch (Exception e) {
-            throw new RuntimeException("Fatal Error: ", e);
+        if (ptg instanceof Ref3DPtg) {
+            Ref3DPtg refPtg = (Ref3DPtg) ptg;
+            Sheet xsheet = workbook.getSheetAt(workbook.getSheetIndexFromExternSheetIndex(refPtg.getExternSheetIndex()));
+            return new LazyRefEval(refPtg, xsheet, workbook);
+        }
+        if (ptg instanceof AreaPtg) {
+            return new LazyAreaEval(((AreaPtg) ptg), sheet, workbook);
+        }
+        if (ptg instanceof Area3DPtg) {
+            Area3DPtg a3dp = (Area3DPtg) ptg;
+            Sheet xsheet = workbook.getSheetAt(workbook.getSheetIndexFromExternSheetIndex(a3dp.getExternSheetIndex()));
+            return new LazyAreaEval(a3dp, xsheet, workbook);
         }
-        return retval;
 
+        if (ptg instanceof IntPtg) {
+            return new NumberEval(((IntPtg)ptg).getValue());
+        }
+        if (ptg instanceof NumberPtg) {
+            return new NumberEval(((NumberPtg)ptg).getValue());
+        }
+        if (ptg instanceof StringPtg) {
+            return new StringEval(((StringPtg) ptg).getValue());
+        }
+        if (ptg instanceof BoolPtg) {
+            return BoolEval.valueOf(((BoolPtg) ptg).getValue());
+        }
+        if (ptg instanceof ErrPtg) {
+            return ErrorEval.valueOf(((ErrPtg) ptg).getErrorCode());
+        }
+        throw new RuntimeException("Unexpected ptg class (" + ptg.getClass().getName() + ")");
     }
-
     /**
      * Given a cell, find its type and from that create an appropriate ValueEval
      * impl instance and return that. Since the cell could be an external
@@ -570,7 +453,7 @@ public class FormulaEvaluator {
      * @param sheet
      * @param workbook
      */
-    protected static ValueEval getEvalForCell(Cell cell, Row row, Sheet sheet, Workbook workbook) {
+    public static ValueEval getEvalForCell(Cell cell, Sheet sheet, Workbook workbook) {
 
         if (cell == null) {
             return BlankEval.INSTANCE;
@@ -593,73 +476,21 @@ public class FormulaEvaluator {
     }
 
     /**
-     * Creates a Ref2DEval for RefPtg.
-     * Non existent cells are treated as RefEvals containing BlankEval.
-     */
-    private static Ref2DEval createRef2DEval(RefPtg ptg, Cell cell, 
-            Sheet sheet, Workbook workbook) {
-        if (cell == null) {
-            return new Ref2DEval(ptg, BlankEval.INSTANCE);
-        }
-        
-        switch (cell.getCellType()) {
-            case Cell.CELL_TYPE_NUMERIC:
-                return new Ref2DEval(ptg, new NumberEval(cell.getNumericCellValue()));
-            case Cell.CELL_TYPE_STRING:
-                return new Ref2DEval(ptg, new StringEval(cell.getRichStringCellValue().getString()));
-            case Cell.CELL_TYPE_FORMULA:
-                return new Ref2DEval(ptg, internalEvaluate(cell, sheet, workbook));
-            case Cell.CELL_TYPE_BOOLEAN:
-                return new Ref2DEval(ptg, BoolEval.valueOf(cell.getBooleanCellValue()));
-            case Cell.CELL_TYPE_BLANK:
-                return new Ref2DEval(ptg, BlankEval.INSTANCE);
-            case Cell.CELL_TYPE_ERROR:
-                return new  Ref2DEval(ptg, ErrorEval.valueOf(cell.getErrorCellValue()));
-        }
-        throw new RuntimeException("Unexpected cell type (" + cell.getCellType() + ")");
-    }
-
-    /**
-     * create a Ref3DEval for Ref3DPtg.
-     */
-    private static Ref3DEval createRef3DEval(Ref3DPtg ptg, Cell cell, 
-            Sheet sheet, Workbook workbook) {
-        if (cell == null) {
-            return new Ref3DEval(ptg, BlankEval.INSTANCE);
-        }
-        switch (cell.getCellType()) {
-            case Cell.CELL_TYPE_NUMERIC:
-                return new Ref3DEval(ptg, new NumberEval(cell.getNumericCellValue()));
-            case Cell.CELL_TYPE_STRING:
-                return new Ref3DEval(ptg, new StringEval(cell.getRichStringCellValue().getString()));
-            case Cell.CELL_TYPE_FORMULA:
-                return new Ref3DEval(ptg, internalEvaluate(cell, sheet, workbook));
-            case Cell.CELL_TYPE_BOOLEAN:
-                return new Ref3DEval(ptg, BoolEval.valueOf(cell.getBooleanCellValue()));
-            case Cell.CELL_TYPE_BLANK:
-                return new Ref3DEval(ptg, BlankEval.INSTANCE);
-            case Cell.CELL_TYPE_ERROR:
-                return new Ref3DEval(ptg, ErrorEval.valueOf(cell.getErrorCellValue()));
-        }
-        throw new RuntimeException("Unexpected cell type (" + cell.getCellType() + ")");
-    }
-    
-    /**
-     * Mimics the 'data view' of a cell. This allows formula evaluator 
+     * Mimics the 'data view' of a cell. This allows formula evaluator
      * to return a CellValue instead of precasting the value to String
      * or Number or boolean type.
      * @author Amol S. Deshmukh &lt; amolweb at ya hoo dot com &gt;
      */
     public static class CellValue {
-    	private CreationHelper creationHelper;
+        private CreationHelper creationHelper;
         private int cellType;
         private RichTextString richTextStringValue;
         private double numberValue;
         private boolean booleanValue;
         private byte errorValue;
-        
+
         /**
-         * CellType should be one of the types defined in HSSFCell
+         * CellType should be one of the types defined in Cell
          * @param cellType
          */
         public CellValue(int cellType, CreationHelper creationHelper) {
@@ -705,8 +536,8 @@ public class FormulaEvaluator {
          * @deprecated
          */
         public void setStringValue(String stringValue) {
-            this.richTextStringValue =
-            	creationHelper.createRichTextString(stringValue);
+            this.richTextStringValue = 
+                  creationHelper.createRichTextString(stringValue);
         }
         /**
          * @return Returns the cellType.
diff --git a/src/java/org/apache/poi/ss/util/AreaReference.java b/src/java/org/apache/poi/ss/util/AreaReference.java
new file mode 100644
index 0000000000..b5e06b9af9
--- /dev/null
+++ b/src/java/org/apache/poi/ss/util/AreaReference.java
@@ -0,0 +1,296 @@
+/* ====================================================================
+   Licensed to the Apache Software Foundation (ASF) under one or more
+   contributor license agreements.  See the NOTICE file distributed with
+   this work for additional information regarding copyright ownership.
+   The ASF licenses this file to You under the Apache License, Version 2.0
+   (the "License"); you may not use this file except in compliance with
+   the License.  You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+==================================================================== */
+
+package org.apache.poi.ss.util;
+
+import java.util.ArrayList;
+import java.util.StringTokenizer;
+
+public class AreaReference {
+
+    /** The character (!) that separates sheet names from cell references */ 
+    private static final char SHEET_NAME_DELIMITER = '!';
+    /** The character (:) that separates the two cell references in a multi-cell area reference */
+    private static final char CELL_DELIMITER = ':';
+    /** The character (') used to quote sheet names when they contain special characters */
+    private static final char SPECIAL_NAME_DELIMITER = '\'';
+    
+    private final CellReference _firstCell;
+    private final CellReference _lastCell;
+    private final boolean _isSingleCell;
+
+    /**
+     * Create an area ref from a string representation.  Sheet names containing special characters should be
+     * delimited and escaped as per normal syntax rules for formulas.<br/> 
+     * The area reference must be contiguous (i.e. represent a single rectangle, not a union of rectangles)
+     */
+    public AreaReference(String reference) {
+        if(! isContiguous(reference)) {
+            throw new IllegalArgumentException(
+                    "References passed to the AreaReference must be contiguous, " +
+                    "use generateContiguous(ref) if you have non-contiguous references");
+        }
+
+        String[] parts = separateAreaRefs(reference);
+        
+        // Special handling for whole-column references
+        if(parts.length == 2 && parts[0].length() == 1 &&
+                parts[1].length() == 1 && 
+                parts[0].charAt(0) >= 'A' && parts[0].charAt(0) <= 'Z' &&
+                parts[1].charAt(0) >= 'A' && parts[1].charAt(0) <= 'Z') {
+            // Represented internally as x$1 to x$65536
+            //  which is the maximum range of rows
+            parts[0] = parts[0] + "$1";
+            parts[1] = parts[1] + "$65536";
+        }
+        
+        _firstCell = new CellReference(parts[0]);
+        
+        if(parts.length == 2) {
+            _lastCell = new CellReference(parts[1]);
+            _isSingleCell = false;
+        } else {
+            _lastCell = _firstCell;
+            _isSingleCell = true;
+        }
+    }
+    
+    /**
+     * Creates an area ref from a pair of Cell References.
+     */
+    public AreaReference(CellReference topLeft, CellReference botRight) {
+        _firstCell = topLeft;
+        _lastCell = botRight;
+        _isSingleCell = false;
+    }
+
+    /**
+     * Is the reference for a contiguous (i.e.
+     *  unbroken) area, or is it made up of
+     *  several different parts?
+     * (If it is, you will need to call
+     *  ....
+     */
+    public static boolean isContiguous(String reference) {
+        if(reference.indexOf(',') == -1) {
+            return true;
+        }
+        return false;
+    }
+    
+    /**
+     * Is the reference for a whole-column reference,
+     *  such as C:C or D:G ?
+     */
+    public static boolean isWholeColumnReference(CellReference topLeft, CellReference botRight) {
+        // These are represented as something like
+        //   C$1:C$65535 or D$1:F$0
+        // i.e. absolute from 1st row to 0th one
+        if(topLeft.getRow() == 0 && topLeft.isRowAbsolute() &&
+            botRight.getRow() == 65535 && botRight.isRowAbsolute()) {
+            return true;
+        }
+        return false;
+    }
+    public boolean isWholeColumnReference() {
+        return isWholeColumnReference(_firstCell, _lastCell);
+    }
+
+    /**
+     * Takes a non-contiguous area reference, and
+     *  returns an array of contiguous area references.
+     */
+    public static AreaReference[] generateContiguous(String reference) {
+        ArrayList refs = new ArrayList();
+        StringTokenizer st = new StringTokenizer(reference, ",");
+        while(st.hasMoreTokens()) {
+            refs.add(
+                    new AreaReference(st.nextToken())
+            );
+        }
+        return (AreaReference[])refs.toArray(new AreaReference[refs.size()]);
+    }
+
+    /**
+     * @return <code>false</code> if this area reference involves more than one cell
+     */
+    public boolean isSingleCell() {
+        return _isSingleCell;
+    }
+    
+    /**
+     * @return the first cell reference which defines this area. Usually this cell is in the upper
+     * left corner of the area (but this is not a requirement).
+     */
+   public CellReference getFirstCell() {
+        return _firstCell;
+    }
+    
+    /**
+     * Note - if this area reference refers to a single cell, the return value of this method will
+     * be identical to that of <tt>getFirstCell()</tt>
+     * @return the second cell reference which defines this area.  For multi-cell areas, this is 
+     * cell diagonally opposite the 'first cell'.  Usually this cell is in the lower right corner 
+     * of the area (but this is not a requirement).
+     */
+    public CellReference getLastCell() {
+        return _lastCell;
+    }
+    /**
+     * Returns a reference to every cell covered by this area
+     */
+    public CellReference[] getAllReferencedCells() {
+        // Special case for single cell reference
+        if(_isSingleCell) {
+            return  new CellReference[] { _firstCell, };
+        }
+ 
+        // Interpolate between the two
+        int minRow = Math.min(_firstCell.getRow(), _lastCell.getRow());
+        int maxRow = Math.max(_firstCell.getRow(), _lastCell.getRow());
+        int minCol = Math.min(_firstCell.getCol(), _lastCell.getCol());
+        int maxCol = Math.max(_firstCell.getCol(), _lastCell.getCol());
+        String sheetName = _firstCell.getSheetName();
+        
+        ArrayList refs = new ArrayList();
+        for(int row=minRow; row<=maxRow; row++) {
+            for(int col=minCol; col<=maxCol; col++) {
+                CellReference ref = new CellReference(sheetName, row, col, _firstCell.isRowAbsolute(), _firstCell.isColAbsolute());
+                refs.add(ref);
+            }
+        }
+        return (CellReference[])refs.toArray(new CellReference[refs.size()]);
+    }
+
+    /**
+     *  Example return values:
+     *    <table border="0" cellpadding="1" cellspacing="0" summary="Example return values">
+     *      <tr><th align='left'>Result</th><th align='left'>Comment</th></tr>
+     *      <tr><td>A1:A1</td><td>Single cell area reference without sheet</td></tr>
+     *      <tr><td>A1:$C$1</td><td>Multi-cell area reference without sheet</td></tr>
+     *      <tr><td>Sheet1!A$1:B4</td><td>Standard sheet name</td></tr>
+     *      <tr><td>'O''Brien''s Sales'!B5:C6'&nbsp;</td><td>Sheet name with special characters</td></tr>
+     *    </table>
+     * @return the text representation of this area reference as it would appear in a formula.
+     */
+    public String formatAsString() {
+        // Special handling for whole-column references
+        if(isWholeColumnReference()) {
+            return
+                CellReference.convertNumToColString(_firstCell.getCol())
+                + ":" +
+                CellReference.convertNumToColString(_lastCell.getCol());
+        }
+        
+        StringBuffer sb = new StringBuffer(32);
+        sb.append(_firstCell.formatAsString());
+        if(!_isSingleCell) {
+            sb.append(CELL_DELIMITER);
+            if(_lastCell.getSheetName() == null) {
+                sb.append(_lastCell.formatAsString());
+            } else {
+                // don't want to include the sheet name twice
+                _lastCell.appendCellReference(sb);
+            }
+        }
+        return sb.toString();
+    }
+
+    public String toString() {
+        StringBuffer sb = new StringBuffer(64);
+        sb.append(getClass().getName()).append(" [");
+        sb.append(formatAsString());
+        sb.append("]");
+        return sb.toString();
+    }
+
+    /**
+     * Separates Area refs in two parts and returns them as separate elements in a String array,
+     * each qualified with the sheet name (if present)
+     * 
+     * @return array with one or two elements. never <code>null</code>
+     */
+    private static String[] separateAreaRefs(String reference) {
+        // TODO - refactor cell reference parsing logic to one place.
+        // Current known incarnations: 
+        //   FormulaParser.GetName()
+        //   CellReference.separateRefParts() 
+        //   AreaReference.separateAreaRefs() (here)
+        //   SheetNameFormatter.format() (inverse)
+        
+        
+        int len = reference.length();
+        int delimiterPos = -1;
+        boolean insideDelimitedName = false;
+        for(int i=0; i<len; i++) {
+            switch(reference.charAt(i)) {
+                case CELL_DELIMITER:
+                    if(!insideDelimitedName) {
+                        if(delimiterPos >=0) {
+                            throw new IllegalArgumentException("More than one cell delimiter '" 
+                                    + CELL_DELIMITER + "' appears in area reference '" + reference + "'");
+                        }
+                        delimiterPos = i;
+                    }
+                default:
+                    continue;
+                case SPECIAL_NAME_DELIMITER:
+                    // fall through
+            }
+            if(!insideDelimitedName) {
+                insideDelimitedName = true;
+                continue;
+            }
+            
+            if(i >= len-1) {
+                // reference ends with the delimited name. 
+                // Assume names like: "Sheet1!'A1'" are never legal.
+                throw new IllegalArgumentException("Area reference '" + reference 
+                        + "' ends with special name delimiter '"  + SPECIAL_NAME_DELIMITER + "'");
+            }
+            if(reference.charAt(i+1) == SPECIAL_NAME_DELIMITER) {
+                // two consecutive quotes is the escape sequence for a single one
+                i++; // skip this and keep parsing the special name
+            } else {
+                // this is the end of the delimited name
+                insideDelimitedName = false;
+            }
+        }
+        if(delimiterPos < 0) {
+            return new String[] { reference, };
+        }
+
+        String partA = reference.substring(0, delimiterPos);
+        String partB = reference.substring(delimiterPos+1);
+        if(partB.indexOf(SHEET_NAME_DELIMITER) >=0) {
+            // TODO - are references like "Sheet1!A1:Sheet1:B2" ever valid?  
+            // FormulaParser has code to handle that.
+            
+            throw new RuntimeException("Unexpected " + SHEET_NAME_DELIMITER 
+                    + " in second cell reference of '" + reference + "'");
+        }
+        
+        int plingPos = partA.lastIndexOf(SHEET_NAME_DELIMITER);
+        if(plingPos < 0) {
+            return new String [] { partA, partB, };
+        }
+        
+        String sheetName = partA.substring(0, plingPos + 1); // +1 to include delimiter
+        
+        return new String [] { partA, sheetName + partB, };
+    }
+}