Memory usage optimizations.

git-svn-id: https://svn.apache.org/repos/asf/xmlgraphics/fop/branches/Temp_AFPGOCAResources@718262 13f79535-47bb-0310-9956-ffa450edef68

21 files changed, 438 insertions, 190 deletions

diff --git a/src/java/org/apache/fop/afp/goca/AbstractGraphicsCoord.java b/src/java/org/apache/fop/afp/goca/AbstractGraphicsCoord.java
index 3adcd9466..066940874 100644
--- a/src/java/org/apache/fop/afp/goca/AbstractGraphicsCoord.java
+++ b/src/java/org/apache/fop/afp/goca/AbstractGraphicsCoord.java
@@ -19,13 +19,18 @@
 
 package org.apache.fop.afp.goca;
 
-import org.apache.fop.afp.modca.AbstractPreparedAFPObject;
+import java.io.IOException;
+import java.io.OutputStream;
+
+import org.apache.fop.afp.modca.AbstractNamedAFPObject;
+import org.apache.fop.afp.modca.StructuredDataObject;
 import org.apache.fop.afp.util.BinaryUtils;
 
 /**
  * A base class encapsulating the structure of coordinate based GOCA objects
  */
-public abstract class AbstractGraphicsCoord extends AbstractPreparedAFPObject {
+public abstract class AbstractGraphicsCoord extends AbstractNamedAFPObject
+    implements StructuredDataObject {
 
     /** array of x/y coordinates */
     protected int[] coords = null;
@@ -37,7 +42,6 @@ public abstract class AbstractGraphicsCoord extends AbstractPreparedAFPObject {
      */
     public AbstractGraphicsCoord(int[] coords) {
         this.coords = coords;
-        prepareData();
     }
 
     /**
@@ -62,40 +66,48 @@ public abstract class AbstractGraphicsCoord extends AbstractPreparedAFPObject {
         this(new int[] {x1, y1, x2, y2});
     }
 
+    /** {@inheritDoc} */
+    public int getDataLength() {
+        return 2 + (coords.length * 2);
+    }
+
     /**
-     * Returns the order code to use
+     * Returns the order code of this structured field
      *
-     * @return the order code to use
+     * @return the order code of this structured field
      */
-    protected abstract byte getOrderCode();
+    abstract byte getOrderCode();
 
     /**
-     * Returns the length of this order code (typically this is the same as the coordinate length)
+     * Returns the coordinate data start index
      *
-     * @return the length of this order code
+     * @return the coordinate data start index
      */
-    protected int getLength() {
-        return this.coords.length * 2;
+    int getCoordinateDataStartIndex() {
+        return 2;
     }
 
     /**
-     * Creates a newly created and initialized byte data
+     * Returns the coordinate data
      *
-     * @return a newly created and initialized byte data
+     * @return the coordinate data
      */
-    protected byte[] createData() {
-        int len = getLength();
-        byte[] data = new byte[len + 2];
-        data[0] = getOrderCode(); // ORDER CODE
-        data[1] = (byte)len; // LENGTH
+    byte[] getData() {
+        int len = getDataLength();
+        byte[] data = new byte[len];
+        data[0] = getOrderCode();
+        data[1] = (byte)(len - 2);
+
+        if (coords != null) {
+            addCoords(data, getCoordinateDataStartIndex());
+        }
+
         return data;
     }
 
     /** {@inheritDoc} */
-    protected void prepareData() {
-        super.data = createData();
-        int fromIndex = data.length - getLength();
-        addCoords(data, fromIndex);
+    public void writeToStream(OutputStream os) throws IOException {
+        os.write(getData());
     }
 
     /**
diff --git a/src/java/org/apache/fop/afp/goca/AbstractGraphicsObjectContainer.java b/src/java/org/apache/fop/afp/goca/AbstractGraphicsObjectContainer.java
new file mode 100644
index 000000000..672193042
--- /dev/null
+++ b/src/java/org/apache/fop/afp/goca/AbstractGraphicsObjectContainer.java
@@ -0,0 +1,83 @@
+/*
+ * 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.
+ */
+
+/* $Id: $ */
+
+package org.apache.fop.afp.goca;
+
+import java.io.IOException;
+import java.io.OutputStream;
+import java.util.Iterator;
+import java.util.List;
+
+import org.apache.fop.afp.modca.AbstractNamedAFPObject;
+import org.apache.fop.afp.modca.StructuredDataObject;
+
+/**
+ * A base container of prepared structured AFP objects
+ */
+public abstract class AbstractGraphicsObjectContainer extends AbstractNamedAFPObject
+implements StructuredDataObject {
+
+    /** list of objects contained within this container */
+    protected List/*<StructuredDataObject>*/ objects
+        = new java.util.ArrayList/*<StructuredDataObject>*/();
+
+    /**
+     * Default constructor
+     */
+    protected AbstractGraphicsObjectContainer() {
+    }
+
+    /**
+     * Named constructor
+     *
+     * @param name the name of the container
+     */
+    protected AbstractGraphicsObjectContainer(String name) {
+        super(name);
+    }
+
+    /** {@inheritDoc} */
+    protected void writeContent(OutputStream os) throws IOException {
+        writeObjects(objects, os);
+    }
+
+    /**
+     * Adds a given graphics object to this container
+     *
+     * @param drawingOrder the graphics object
+     */
+    public void addObject(StructuredDataObject drawingOrder) {
+        objects.add(drawingOrder);
+    }
+
+    /**
+     * Returns the current data length
+     *
+     * @return the current data length of this container including
+     * all enclosed objects (and their containers)
+     */
+    public int getDataLength() {
+        int dataLen = 0;
+        Iterator it = objects.iterator();
+        while (it.hasNext()) {
+            dataLen += ((StructuredDataObject)it.next()).getDataLength();
+        }
+        return dataLen;
+    }
+}
diff --git a/src/java/org/apache/fop/afp/goca/AbstractGraphicsString.java b/src/java/org/apache/fop/afp/goca/AbstractGraphicsString.java
new file mode 100644
index 000000000..80882db8a
--- /dev/null
+++ b/src/java/org/apache/fop/afp/goca/AbstractGraphicsString.java
@@ -0,0 +1,74 @@
+/*
+ * 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.
+ */
+
+/* $Id$ */
+
+package org.apache.fop.afp.goca;
+
+import java.io.UnsupportedEncodingException;
+
+import org.apache.fop.afp.AFPConstants;
+
+public abstract class AbstractGraphicsString extends AbstractGraphicsCoord {
+
+    /** Up to 255 bytes of character data */
+    protected static final int MAX_STR_LEN = 255;
+
+    /** the string to draw */
+    protected final String str;
+
+    /**
+     * Constructor (relative)
+     *
+     * @param str the text string
+     */
+    public AbstractGraphicsString(String str) {
+        super(null);
+        if (str.length() > MAX_STR_LEN) {
+            str = str.substring(0, MAX_STR_LEN);
+            log.warn("truncated character string, longer than " + MAX_STR_LEN + " chars");
+        }
+        this.str = str;
+    }
+
+    /**
+     * Constructor (absolute)
+     *
+     * @param str the text string
+     * @param x the x coordinate
+     * @param y the y coordinate
+     */
+    public AbstractGraphicsString(String str, int x, int y) {
+        super(x, y);
+        this.str = str;
+    }
+
+    /** {@inheritDoc} */
+    public int getDataLength() {
+        return 2 + str.length();
+    }
+
+    /**
+     * Returns the text string as an encoded byte array
+     *
+     * @return the text string as an encoded byte array
+     */
+    protected byte[] getStringAsBytes() throws UnsupportedEncodingException {
+        return str.getBytes(AFPConstants.EBCIDIC_ENCODING);
+    }
+
+}
diff --git a/src/java/org/apache/fop/afp/goca/GraphicsArea.java b/src/java/org/apache/fop/afp/goca/GraphicsArea.java
index 2b6d8a804..3d3bafb45 100644
--- a/src/java/org/apache/fop/afp/goca/GraphicsArea.java
+++ b/src/java/org/apache/fop/afp/goca/GraphicsArea.java
@@ -22,12 +22,11 @@ package org.apache.fop.afp.goca;
 import java.io.IOException;
 import java.io.OutputStream;
 
-import org.apache.fop.afp.modca.AbstractPreparedObjectContainer;
 
 /**
  * A GOCA graphics area (container for filled shapes/objects)
  */
-public final class GraphicsArea extends AbstractPreparedObjectContainer {
+public final class GraphicsArea extends AbstractGraphicsObjectContainer {
 
     private static final int RES1 = 1;
     private static final int BOUNDARY = 2;
@@ -47,7 +46,6 @@ public final class GraphicsArea extends AbstractPreparedObjectContainer {
 
     /** {@inheritDoc} */
     public int getDataLength() {
-        // start len + end len + data len
         return 4 + super.getDataLength();
     }
 
@@ -62,11 +60,11 @@ public final class GraphicsArea extends AbstractPreparedObjectContainer {
 
     /** {@inheritDoc} */
     protected void writeEnd(OutputStream os) throws IOException {
-        byte[] endData = new byte[] {
+        byte[] data = new byte[] {
             (byte)0x60, // GEAR order code
             0x00, // LENGTH
         };
-        os.write(endData);
+        os.write(data);
     }
 
     /** {@inheritDoc} */
diff --git a/src/java/org/apache/fop/afp/goca/GraphicsBox.java b/src/java/org/apache/fop/afp/goca/GraphicsBox.java
index 4f4947000..945697ec2 100644
--- a/src/java/org/apache/fop/afp/goca/GraphicsBox.java
+++ b/src/java/org/apache/fop/afp/goca/GraphicsBox.java
@@ -19,6 +19,9 @@
 
 package org.apache.fop.afp.goca;
 
+import java.io.IOException;
+import java.io.OutputStream;
+
 /**
  * A GOCA graphics rectangular box
  */
@@ -34,28 +37,27 @@ public final class GraphicsBox extends AbstractGraphicsCoord {
     }
 
     /** {@inheritDoc} */
-    protected byte getOrderCode() {
-        return (byte)0xC0;
+    public int getDataLength() {
+        return 12;
     }
 
     /** {@inheritDoc} */
-    protected int getLength() {
-        return 10;
+    int getCoordinateDataStartIndex() {
+        return 4;
     }
 
     /** {@inheritDoc} */
-    protected void prepareData() {
-        super.data = createData();
-        final int fromIndex = 4;
-        addCoords(data, fromIndex);
+    byte getOrderCode() {
+        return (byte)0xC0;
     }
 
     /** {@inheritDoc} */
-    protected byte[] createData() {
-        byte[] data = super.createData();
+    public void writeToStream(OutputStream os) throws IOException {
+        byte[] data = getData();
         data[2] = (byte)0x20; // CONTROL draw control flags
         data[3] = 0x00; // reserved
-        return data;
+
+        os.write(data);
     }
 
 }
\ No newline at end of file
diff --git a/src/java/org/apache/fop/afp/goca/GraphicsChainedSegment.java b/src/java/org/apache/fop/afp/goca/GraphicsChainedSegment.java
index 8dab3d922..697d4f841 100644
--- a/src/java/org/apache/fop/afp/goca/GraphicsChainedSegment.java
+++ b/src/java/org/apache/fop/afp/goca/GraphicsChainedSegment.java
@@ -22,14 +22,13 @@ package org.apache.fop.afp.goca;
 import java.io.IOException;
 import java.io.OutputStream;
 
-import org.apache.fop.afp.modca.AbstractPreparedObjectContainer;
-import org.apache.fop.afp.modca.PreparedAFPObject;
+import org.apache.fop.afp.modca.StructuredDataObject;
 import org.apache.fop.afp.util.BinaryUtils;
 
 /**
  * A GOCA graphics segment
  */
-public final class GraphicsChainedSegment extends AbstractPreparedObjectContainer {
+public final class GraphicsChainedSegment extends AbstractGraphicsObjectContainer {
 
     /** The maximum segment data length */
     protected static final int MAX_DATA_LEN = 8192;
@@ -84,11 +83,16 @@ public final class GraphicsChainedSegment extends AbstractPreparedObjectContaine
     }
 
     /** {@inheritDoc} */
+    byte getOrderCode() {
+        return 0x70;
+    }
+
+    /** {@inheritDoc} */
     protected void writeStart(OutputStream os) throws IOException {
         super.writeStart(os);
 
         byte[] data = new byte[14];
-        data[0] = 0x70; // BEGIN_SEGMENT
+        data[0] = getOrderCode(); // BEGIN_SEGMENT
         data[1] = 0x0C; // Length of following parameters
 
         // segment name
@@ -133,7 +137,7 @@ public final class GraphicsChainedSegment extends AbstractPreparedObjectContaine
     }
 
     /** {@inheritDoc} */
-    public void addObject(PreparedAFPObject drawingOrder) {
+    public void addObject(StructuredDataObject drawingOrder) {
         if (currentArea != null) {
             currentArea.addObject(drawingOrder);
         } else {
diff --git a/src/java/org/apache/fop/afp/goca/GraphicsData.java b/src/java/org/apache/fop/afp/goca/GraphicsData.java
index ca5fef3f4..8b59436fc 100644
--- a/src/java/org/apache/fop/afp/goca/GraphicsData.java
+++ b/src/java/org/apache/fop/afp/goca/GraphicsData.java
@@ -22,21 +22,20 @@ package org.apache.fop.afp.goca;
 import java.io.IOException;
 import java.io.OutputStream;
 
-import org.apache.fop.afp.modca.AbstractPreparedObjectContainer;
-import org.apache.fop.afp.modca.PreparedAFPObject;
+import org.apache.fop.afp.modca.StructuredDataObject;
 import org.apache.fop.afp.util.BinaryUtils;
 import org.apache.fop.afp.util.StringUtils;
 
 /**
  * A GOCA graphics data
  */
-public final class GraphicsData extends AbstractPreparedObjectContainer {
+public final class GraphicsData extends AbstractGraphicsObjectContainer {
 
     /** The maximum graphics data length */
     public static final int MAX_DATA_LEN = 32767;
 
     /** The graphics segment */
-    private GraphicsChainedSegment currentSegment = null;
+    private GraphicsChainedSegment segment = null;
 
     /** {@inheritDoc} */
     public int getDataLength() {
@@ -74,10 +73,10 @@ public final class GraphicsData extends AbstractPreparedObjectContainer {
      * @return the current graphics chained segment
      */
     private GraphicsChainedSegment getSegment() {
-        if (currentSegment == null) {
+        if (segment == null) {
             newSegment();
         }
-        return this.currentSegment;
+        return this.segment;
     }
 
     /**
@@ -87,23 +86,23 @@ public final class GraphicsData extends AbstractPreparedObjectContainer {
      */
     public GraphicsChainedSegment newSegment() {
         String name = createSegmentName();
-        if (currentSegment == null) {
-            this.currentSegment = new GraphicsChainedSegment(name);
+        if (segment == null) {
+            this.segment = new GraphicsChainedSegment(name);
         } else {
-            this.currentSegment = new GraphicsChainedSegment(name, currentSegment);
+            this.segment = new GraphicsChainedSegment(name, segment);
         }
-        super.addObject(currentSegment);
-        return currentSegment;
+        super.addObject(segment);
+        return segment;
     }
 
     /** {@inheritDoc} */
-    public void addObject(PreparedAFPObject drawingOrder) {
-        if (currentSegment == null
-            || (currentSegment.getDataLength() + drawingOrder.getDataLength())
+    public void addObject(StructuredDataObject drawingOrder) {
+        if (segment == null
+            || (segment.getDataLength() + drawingOrder.getDataLength())
             >= GraphicsChainedSegment.MAX_DATA_LEN) {
             newSegment();
         }
-        currentSegment.addObject(drawingOrder);
+        segment.addObject(drawingOrder);
     }
 
     /** {@inheritDoc} */
diff --git a/src/java/org/apache/fop/afp/goca/GraphicsFillet.java b/src/java/org/apache/fop/afp/goca/GraphicsFillet.java
index 40b98b0d3..b4fa17d65 100644
--- a/src/java/org/apache/fop/afp/goca/GraphicsFillet.java
+++ b/src/java/org/apache/fop/afp/goca/GraphicsFillet.java
@@ -34,8 +34,7 @@ public final class GraphicsFillet extends AbstractGraphicsCoord {
         super(coords);
     }
 
-    /** {@inheritDoc} */
-    protected byte getOrderCode() {
+    byte getOrderCode() {
         return (byte)0xC5;
     }
 
diff --git a/src/java/org/apache/fop/afp/goca/GraphicsFilletRelative.java b/src/java/org/apache/fop/afp/goca/GraphicsFilletRelative.java
index b0e408405..21a1c17d6 100644
--- a/src/java/org/apache/fop/afp/goca/GraphicsFilletRelative.java
+++ b/src/java/org/apache/fop/afp/goca/GraphicsFilletRelative.java
@@ -19,6 +19,7 @@
 
 package org.apache.fop.afp.goca;
 
+
 /**
  * A GOCA graphics curved tangential line to a specified set of
  * straight lines drawn from the given position or current position
@@ -35,8 +36,7 @@ public final class GraphicsFilletRelative extends AbstractGraphicsCoord {
     }
 
     /** {@inheritDoc} */
-    protected byte getOrderCode() {
+    byte getOrderCode() {
         return (byte)0x85;
     }
-
 }
\ No newline at end of file
diff --git a/src/java/org/apache/fop/afp/goca/GraphicsFullArc.java b/src/java/org/apache/fop/afp/goca/GraphicsFullArc.java
index 9d511e142..a4b6916ae 100644
--- a/src/java/org/apache/fop/afp/goca/GraphicsFullArc.java
+++ b/src/java/org/apache/fop/afp/goca/GraphicsFullArc.java
@@ -19,12 +19,16 @@
 
 package org.apache.fop.afp.goca;
 
+import java.io.IOException;
+import java.io.OutputStream;
+
 import org.apache.fop.afp.util.BinaryUtils;
 
 /**
  * A GOCA graphics arc (circle/ellipse)
  */
 public class GraphicsFullArc extends AbstractGraphicsCoord {
+
     /** the integer portion of the multiplier */
     private final int mh;
 
@@ -43,27 +47,29 @@ public class GraphicsFullArc extends AbstractGraphicsCoord {
         super(x, y);
         this.mh = mh;
         this.mhr = mhr;
-        // integer portion of multiplier
-        data[data.length - 2] = BinaryUtils.convert(mh, 1)[0];
-        // fractional portion of multiplier
-        data[data.length - 1] = BinaryUtils.convert(mhr, 1)[0];
     }
 
     /** {@inheritDoc} */
-    protected byte getOrderCode() {
-        return (byte)0xC7;
+    public int getDataLength() {
+        return 8;
     }
 
     /** {@inheritDoc} */
-    protected int getLength() {
-        return super.getLength() + 2;
+    byte getOrderCode() {
+        return (byte)0xC7;
     }
 
     /** {@inheritDoc} */
-    protected void prepareData() {
-        super.data = super.createData();
-        final int fromIndex = 2;
-        super.addCoords(data, fromIndex);
+    public void writeToStream(OutputStream os) throws IOException {
+        byte[] data = getData();
+
+        // integer portion of multiplier
+        data[6] = BinaryUtils.convert(mh, 1)[0];
+
+        // fractional portion of multiplier
+        data[7] = BinaryUtils.convert(mhr, 1)[0];
+
+        os.write(data);
     }
 
     /** {@inheritDoc} */
@@ -75,4 +81,5 @@ public class GraphicsFullArc extends AbstractGraphicsCoord {
              + ", mhr=" + mhr
          + "}";
     }
+
 }
\ No newline at end of file
diff --git a/src/java/org/apache/fop/afp/goca/GraphicsImage.java b/src/java/org/apache/fop/afp/goca/GraphicsImage.java
index 24d4c78f8..94e9e9ab2 100644
--- a/src/java/org/apache/fop/afp/goca/GraphicsImage.java
+++ b/src/java/org/apache/fop/afp/goca/GraphicsImage.java
@@ -22,13 +22,13 @@ package org.apache.fop.afp.goca;
 import java.io.IOException;
 import java.io.OutputStream;
 
-import org.apache.fop.afp.modca.AbstractStructuredAFPObject;
+import org.apache.fop.afp.modca.AbstractStructuredObject;
 import org.apache.fop.afp.util.BinaryUtils;
 
 /**
  * A GOCA Image
  */
-public class GraphicsImage extends AbstractStructuredAFPObject {
+public class GraphicsImage extends AbstractStructuredObject {
 
     /** x coordinate */
     private final int x;
diff --git a/src/java/org/apache/fop/afp/goca/GraphicsLine.java b/src/java/org/apache/fop/afp/goca/GraphicsLine.java
index 99f54b2d1..d8ff1afaa 100644
--- a/src/java/org/apache/fop/afp/goca/GraphicsLine.java
+++ b/src/java/org/apache/fop/afp/goca/GraphicsLine.java
@@ -21,7 +21,7 @@ package org.apache.fop.afp.goca;
 
 /**
  * A GOCA graphics straight line drawn from the
- * given position
+ * given absolute position
  */
 public class GraphicsLine extends AbstractGraphicsCoord {
 
@@ -35,7 +35,7 @@ public class GraphicsLine extends AbstractGraphicsCoord {
     }
 
     /** {@inheritDoc} */
-    protected byte getOrderCode() {
+    byte getOrderCode() {
         return (byte)0xC1;
     }
 
diff --git a/src/java/org/apache/fop/afp/goca/GraphicsLineRelative.java b/src/java/org/apache/fop/afp/goca/GraphicsLineRelative.java
index 1eddc5129..43ffebf08 100644
--- a/src/java/org/apache/fop/afp/goca/GraphicsLineRelative.java
+++ b/src/java/org/apache/fop/afp/goca/GraphicsLineRelative.java
@@ -35,7 +35,7 @@ public class GraphicsLineRelative extends AbstractGraphicsCoord {
     }
 
     /** {@inheritDoc} */
-    protected byte getOrderCode() {
+    byte getOrderCode() {
         return (byte)0x81;
     }
 
diff --git a/src/java/org/apache/fop/afp/goca/GraphicsSetCharacterSet.java b/src/java/org/apache/fop/afp/goca/GraphicsSetCharacterSet.java
index f4d04910a..1561ecf83 100644
--- a/src/java/org/apache/fop/afp/goca/GraphicsSetCharacterSet.java
+++ b/src/java/org/apache/fop/afp/goca/GraphicsSetCharacterSet.java
@@ -19,13 +19,18 @@
 
 package org.apache.fop.afp.goca;
 
-import org.apache.fop.afp.modca.AbstractPreparedAFPObject;
+import java.io.IOException;
+import java.io.OutputStream;
+
+import org.apache.fop.afp.modca.AbstractNamedAFPObject;
+import org.apache.fop.afp.modca.StructuredDataObject;
 import org.apache.fop.afp.util.BinaryUtils;
 
 /**
  * Sets the current character set (font) to be used for following graphics strings
  */
-public class GraphicsSetCharacterSet extends AbstractPreparedAFPObject {
+public class GraphicsSetCharacterSet extends AbstractNamedAFPObject
+    implements StructuredDataObject {
 
     /** font character set reference */
     private final int fontReference;
@@ -35,19 +40,25 @@ public class GraphicsSetCharacterSet extends AbstractPreparedAFPObject {
      */
     public GraphicsSetCharacterSet(int fontReference) {
         this.fontReference = fontReference;
-        prepareData();
     }
 
     /** {@inheritDoc} */
-    protected void prepareData() {
-        super.data = new byte[] {
+    public void writeToStream(OutputStream os) throws IOException {
+        byte[] data = new byte[] {
             0x38, // GSCS order code
             BinaryUtils.convert(fontReference)[0]
         };
+        os.write(data);
+    }
+
+    /** {@inheritDoc} */
+    public int getDataLength() {
+        return 2;
     }
 
     /** {@inheritDoc} */
     public String toString() {
         return "GraphicsSetCharacterSet(" + fontReference + ")";
     }
+
 }
\ No newline at end of file
diff --git a/src/java/org/apache/fop/afp/goca/GraphicsSetLineType.java b/src/java/org/apache/fop/afp/goca/GraphicsSetLineType.java
index 0093885a6..3479bf4e5 100644
--- a/src/java/org/apache/fop/afp/goca/GraphicsSetLineType.java
+++ b/src/java/org/apache/fop/afp/goca/GraphicsSetLineType.java
@@ -19,12 +19,17 @@
 
 package org.apache.fop.afp.goca;
 
-import org.apache.fop.afp.modca.AbstractPreparedAFPObject;
+import java.io.IOException;
+import java.io.OutputStream;
+
+import org.apache.fop.afp.modca.AbstractNamedAFPObject;
+import org.apache.fop.afp.modca.StructuredDataObject;
 
 /**
  * Sets the value of the current line type attribute when stroking GOCA shapes (structured fields)
  */
-public class GraphicsSetLineType extends AbstractPreparedAFPObject {
+public class GraphicsSetLineType extends AbstractNamedAFPObject
+implements StructuredDataObject {
 
     /** the default line type */
     public static final byte DEFAULT = 0x00; // normally SOLID
@@ -63,15 +68,20 @@ public class GraphicsSetLineType extends AbstractPreparedAFPObject {
      */
     public GraphicsSetLineType(byte type) {
        this.type = type;
-       prepareData();
     }
 
     /** {@inheritDoc} */
-    protected void prepareData() {
-        super.data = new byte[] {
-           0x18, // GSLW order code
-           type // line type
+    public int getDataLength() {
+        return 2;
+    }
+
+    /** {@inheritDoc} */
+    public void writeToStream(OutputStream os) throws IOException {
+        byte[] data = new byte[] {
+            0x18, // GSLW order code
+            type // line type
         };
+        os.write(data);
     }
 
     private static final String[] TYPES = {
diff --git a/src/java/org/apache/fop/afp/goca/GraphicsSetLineWidth.java b/src/java/org/apache/fop/afp/goca/GraphicsSetLineWidth.java
index 863cbf50d..09ed0d7dc 100644
--- a/src/java/org/apache/fop/afp/goca/GraphicsSetLineWidth.java
+++ b/src/java/org/apache/fop/afp/goca/GraphicsSetLineWidth.java
@@ -19,12 +19,17 @@
 
 package org.apache.fop.afp.goca;
 
-import org.apache.fop.afp.modca.AbstractPreparedAFPObject;
+import java.io.IOException;
+import java.io.OutputStream;
+
+import org.apache.fop.afp.modca.AbstractNamedAFPObject;
+import org.apache.fop.afp.modca.StructuredDataObject;
 
 /**
  * Sets the line width to use when stroking GOCA shapes (structured fields)
  */
-public class GraphicsSetLineWidth extends AbstractPreparedAFPObject {
+public class GraphicsSetLineWidth extends AbstractNamedAFPObject implements StructuredDataObject {
+
     /** line width multiplier */
     private int multiplier = 1;
 
@@ -35,15 +40,20 @@ public class GraphicsSetLineWidth extends AbstractPreparedAFPObject {
      */
     public GraphicsSetLineWidth(int multiplier) {
         this.multiplier = multiplier;
-        prepareData();
     }
 
     /** {@inheritDoc} */
-    protected void prepareData() {
-        super.data = new byte[] {
+    public int getDataLength() {
+        return 2;
+    }
+
+    /** {@inheritDoc} */
+    public void writeToStream(OutputStream os) throws IOException {
+        byte[] data = new byte[] {
            0x19, // GSLW order code
            (byte)multiplier // MH (line-width)
         };
+        os.write(data);
     }
 
     /** {@inheritDoc} */
diff --git a/src/java/org/apache/fop/afp/goca/GraphicsSetMix.java b/src/java/org/apache/fop/afp/goca/GraphicsSetMix.java
index 339620271..0058a5013 100644
--- a/src/java/org/apache/fop/afp/goca/GraphicsSetMix.java
+++ b/src/java/org/apache/fop/afp/goca/GraphicsSetMix.java
@@ -19,9 +19,12 @@
 
 package org.apache.fop.afp.goca;
 
-import org.apache.fop.afp.modca.AbstractPreparedAFPObject;
+import java.io.IOException;
+import java.io.OutputStream;
 
-public class GraphicsSetMix extends AbstractPreparedAFPObject {
+import org.apache.fop.afp.modca.AbstractNamedAFPObject;
+
+public class GraphicsSetMix extends AbstractNamedAFPObject {
 
     public static final byte MODE_DEFAULT = 0x00;
     public static final byte MODE_OVERPAINT = 0x02;
@@ -36,15 +39,15 @@ public class GraphicsSetMix extends AbstractPreparedAFPObject {
      */
     public GraphicsSetMix(byte mode) {
         this.mode = mode;
-        prepareData();
     }
 
     /** {@inheritDoc} */
-    protected void prepareData() {
-        super.data = new byte[] {
+    public void writeToStream(OutputStream os) throws IOException {
+        byte[] data = new byte[] {
            0x0C, // GSMX order code
            mode // MODE (mix mode value)
         };
+        os.write(data);
     }
 
     /** {@inheritDoc} */
diff --git a/src/java/org/apache/fop/afp/goca/GraphicsSetPatternSymbol.java b/src/java/org/apache/fop/afp/goca/GraphicsSetPatternSymbol.java
index f0e6845be..0d74aa9d3 100644
--- a/src/java/org/apache/fop/afp/goca/GraphicsSetPatternSymbol.java
+++ b/src/java/org/apache/fop/afp/goca/GraphicsSetPatternSymbol.java
@@ -19,12 +19,18 @@
 
 package org.apache.fop.afp.goca;
 
-import org.apache.fop.afp.modca.AbstractPreparedAFPObject;
+import java.io.IOException;
+import java.io.OutputStream;
+
+import org.apache.fop.afp.modca.AbstractNamedAFPObject;
+import org.apache.fop.afp.modca.StructuredDataObject;
 
 /**
  * Sets the pattern symbol to use when filling following GOCA structured fields
  */
-public class GraphicsSetPatternSymbol extends AbstractPreparedAFPObject {
+public class GraphicsSetPatternSymbol extends AbstractNamedAFPObject
+implements StructuredDataObject {
+
     /** dotted density 1 */
     public static final byte DOTTED_DENSITY_1 = 0x01;
 
@@ -86,15 +92,20 @@ public class GraphicsSetPatternSymbol extends AbstractPreparedAFPObject {
      */
     public GraphicsSetPatternSymbol(byte symb) {
         this.symbol = symb;
-        prepareData();
     }
 
     /** {@inheritDoc} */
-    protected void prepareData() {
-        super.data = new byte[] {
+    public int getDataLength() {
+        return 2;
+    }
+
+    /** {@inheritDoc} */
+    public void writeToStream(OutputStream os) throws IOException {
+        byte[] data = new byte[] {
             0x28, // GSPT order code
             symbol
         };
+        os.write(data);
     }
 
     /** {@inheritDoc} */
diff --git a/src/java/org/apache/fop/afp/goca/GraphicsSetProcessColor.java b/src/java/org/apache/fop/afp/goca/GraphicsSetProcessColor.java
index 6ec1e50ee..41ddeaa96 100644
--- a/src/java/org/apache/fop/afp/goca/GraphicsSetProcessColor.java
+++ b/src/java/org/apache/fop/afp/goca/GraphicsSetProcessColor.java
@@ -21,16 +21,22 @@ package org.apache.fop.afp.goca;
 
 import java.awt.Color;
 import java.awt.color.ColorSpace;
+import java.io.IOException;
+import java.io.OutputStream;
 
-import org.apache.fop.afp.modca.AbstractPreparedAFPObject;
+import org.apache.fop.afp.modca.AbstractNamedAFPObject;
+import org.apache.fop.afp.modca.StructuredDataObject;
 
 /**
  * Sets the current processing color for the following GOCA structured fields
  */
-public class GraphicsSetProcessColor extends AbstractPreparedAFPObject {
-    /** the color to set */
+public class GraphicsSetProcessColor extends AbstractNamedAFPObject
+implements StructuredDataObject {
+
     private final Color color;
 
+    private final float[] colorComponents;
+
     /**
      * Main constructor
      *
@@ -38,11 +44,22 @@ public class GraphicsSetProcessColor extends AbstractPreparedAFPObject {
      */
     public GraphicsSetProcessColor(Color color) {
         this.color = color;
-        prepareData();
+        this.colorComponents = color.getColorComponents(null);
+    }
+
+    /** {@inheritDoc} */
+    public int getDataLength() {
+        return 12 + colorComponents.length;
     }
 
     /** {@inheritDoc} */
-    protected void prepareData() {
+    byte getOrderCode() {
+        return (byte)0xB2;
+    }
+
+    /** {@inheritDoc} */
+    public void writeToStream(OutputStream os) throws IOException {
+
         // COLSPCE
         byte colspace;
         int colSpaceType = color.getColorSpace().getType();
@@ -56,16 +73,15 @@ public class GraphicsSetProcessColor extends AbstractPreparedAFPObject {
         }
 
         // COLSIZE(S)
-        float[] colcomp = color.getColorComponents(null);
         byte[] colsizes = new byte[] {0x00, 0x00, 0x00, 0x00};
-        for (int i = 0; i < colcomp.length; i++) {
+        for (int i = 0; i < colorComponents.length; i++) {
             colsizes[i] = (byte)8;
         }
 
-        int len = 10 + colcomp.length;
-        super.data = new byte[len + 2];
-        data[0] = (byte)0xB2; // GSPCOL order code
-        data[1] = (byte)len; // LEN
+        int len = getDataLength();
+        byte[] data = new byte[len];
+        data[0] = getOrderCode(); // GSPCOL order code
+        data[1] = (byte)(len - 2); // LEN
         data[2] = 0x00; // reserved; must be zero
         data[3] = colspace; // COLSPCE
         data[4] = 0x00; // reserved; must be zero
@@ -76,10 +92,13 @@ public class GraphicsSetProcessColor extends AbstractPreparedAFPObject {
         data[9] = colsizes[1];
         data[10] = colsizes[2];
         data[11] = colsizes[3];
+
         // COLVALUE(S)
-        for (int i = 0; i < colcomp.length; i++) {
-            data[i + 12] = (byte)(colcomp[i] * 255);
+        for (int i = 0; i < colorComponents.length; i++) {
+            data[i + 12] = (byte)(colorComponents[i] * 255);
         }
+
+        os.write(data);
     }
 
     /** {@inheritDoc} */
diff --git a/src/java/org/apache/fop/afp/goca/GraphicsString.java b/src/java/org/apache/fop/afp/goca/GraphicsString.java
index 0fa14bb6d..c08da64ec 100644
--- a/src/java/org/apache/fop/afp/goca/GraphicsString.java
+++ b/src/java/org/apache/fop/afp/goca/GraphicsString.java
@@ -19,41 +19,13 @@
 
 package org.apache.fop.afp.goca;
 
-import java.io.UnsupportedEncodingException;
-
-import org.apache.fop.afp.AFPConstants;
-import org.apache.fop.afp.modca.AbstractPreparedAFPObject;
-import org.apache.fop.afp.util.BinaryUtils;
+import java.io.IOException;
+import java.io.OutputStream;
 
 /**
  * A GOCA graphics string
  */
-public class GraphicsString extends AbstractPreparedAFPObject {
-    /** Up to 255 bytes of character data */
-    private static final int MAX_STR_LEN = 255;
-
-    /** drawn from the current position */
-    private boolean fromCurrentPosition = false;
-
-    /** the string to draw */
-    private String str = null;
-
-    /** x coordinate */
-    private int x;
-
-    /** y coordinate */
-    private int y;
-
-    /**
-     * Constructor
-     *
-     * @param str the character string
-     */
-    public GraphicsString(String str) {
-        this.str  = str;
-        fromCurrentPosition = true;
-        prepareData();
-    }
+public class GraphicsString extends AbstractGraphicsString {
 
     /**
      * Constructor
@@ -63,53 +35,30 @@ public class GraphicsString extends AbstractPreparedAFPObject {
      * @param y the y coordinate
      */
     public GraphicsString(String str, int x, int y) {
-        this.str = str;
-        this.x = x;
-        this.y = y;
-        prepareData();
+        super(str, x, y);
+    }
+
+    /** {@inheritDoc} */
+    byte getOrderCode() {
+        return (byte)0xC3;
     }
 
     /** {@inheritDoc} */
-    protected void prepareData() {
-        int maxStrLen = MAX_STR_LEN - (fromCurrentPosition ? 0 : 4);
-        if (str.length() > maxStrLen) {
-            str = str.substring(0, maxStrLen);
-            log.warn("truncated character string, longer than " + maxStrLen + " chars");
-        }
-        byte[] strData = null;
-        try {
-            strData = str.getBytes(AFPConstants.EBCIDIC_ENCODING);
-        } catch (UnsupportedEncodingException ex) {
-            log.error("unsupported encoding: " + ex.getMessage());
-        }
-        int len = strData.length;
-        if (fromCurrentPosition) {
-            data = new byte[len + 2];
-            data[0] = (byte)0x83;
-            data[1] = (byte)len;
-            System.arraycopy(strData, 0, data, 2, strData.length);
-        } else {
-            len += 4; // x/y coordinates
-            byte[] osx = BinaryUtils.convert(x, 2);
-            byte[] osy = BinaryUtils.convert(y, 2);
-            data = new byte[len + 2];
-            data[0] = (byte)0xC3;
-            data[1] = (byte)len;
-            data[2] = osx[0];
-            data[3] = osx[1];
-            data[4] = osy[0];
-            data[5] = osy[1];
-            System.arraycopy(strData, 0, data, 6, strData.length);
-        }
+    public int getDataLength() {
+        return super.getDataLength() + (coords.length * 2);
+    }
+
+    /** {@inheritDoc} */
+    public void writeToStream(OutputStream os) throws IOException {
+        byte[] data = getData();
+        byte[] strData = getStringAsBytes();
+        System.arraycopy(strData, 0, data, 6, strData.length);
+
+        os.write(data);
     }
 
     /** {@inheritDoc} */
     public String toString() {
-        String string = "GraphicsString{str='" + str + "'";
-        if (!fromCurrentPosition) {
-            string += ",x=" + x + ",y=" + y;
-        }
-        string += "}";
-        return string;
+        return "GraphicsString{x=" + coords[0] + ", y=" + coords[1] + "str='" + str + "'" + "}";
     }
 }
\ No newline at end of file
diff --git a/src/java/org/apache/fop/afp/goca/GraphicsStringRelative.java b/src/java/org/apache/fop/afp/goca/GraphicsStringRelative.java
new file mode 100644
index 000000000..af0c05b5d
--- /dev/null
+++ b/src/java/org/apache/fop/afp/goca/GraphicsStringRelative.java
@@ -0,0 +1,57 @@
+/*
+ * 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.
+ */
+
+/* $Id$ */
+
+package org.apache.fop.afp.goca;
+
+import java.io.IOException;
+import java.io.OutputStream;
+
+/**
+ * A GOCA graphics string
+ */
+public class GraphicsStringRelative extends AbstractGraphicsString {
+
+    /**
+     * Constructor
+     *
+     * @param str the character string
+     */
+    public GraphicsStringRelative(String str) {
+        super(str);
+    }
+
+    /** {@inheritDoc} */
+    byte getOrderCode() {
+        return (byte)0x83;
+    }
+
+    /** {@inheritDoc} */
+    public void writeToStream(OutputStream os) throws IOException {
+        byte[] data = getData();
+        byte[] strData = getStringAsBytes();
+        System.arraycopy(strData, 0, data, 2, strData.length);
+        os.write(data);
+    }
+
+    /** {@inheritDoc} */
+    public String toString() {
+        return "GraphicsStringRelative{str='" + str + "'" + "}";
+    }
+
+}
\ No newline at end of file