use zero size arg to toArray(), use Collection.addAll() (#63805, second patch)

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1869919 13f79535-47bb-0310-9956-ffa450edef68

18 files changed, 30 insertions, 51 deletions

diff --git a/src/java/org/apache/poi/ddf/EscherDggRecord.java b/src/java/org/apache/poi/ddf/EscherDggRecord.java
index 188a63ee57..89e133eca7 100644
--- a/src/java/org/apache/poi/ddf/EscherDggRecord.java
+++ b/src/java/org/apache/poi/ddf/EscherDggRecord.java
@@ -219,7 +219,7 @@ public final class EscherDggRecord extends EscherRecord {
      * @return the file id clusters
      */
     public FileIdCluster[] getFileIdClusters() {
-        return field_5_fileIdClusters.toArray(new FileIdCluster[field_5_fileIdClusters.size()]);
+        return field_5_fileIdClusters.toArray(new FileIdCluster[0]);
     }
 
     /**
diff --git a/src/java/org/apache/poi/hpsf/Vector.java b/src/java/org/apache/poi/hpsf/Vector.java
index d82c215b70..465eabd829 100644
--- a/src/java/org/apache/poi/hpsf/Vector.java
+++ b/src/java/org/apache/poi/hpsf/Vector.java
@@ -58,7 +58,7 @@ public class Vector {
             }
             values.add(value);
         }
-        _values = values.toArray(new TypedPropertyValue[values.size()]);
+        _values = values.toArray(new TypedPropertyValue[0]);
     }
 
     public TypedPropertyValue[] getValues(){
diff --git a/src/java/org/apache/poi/hssf/eventusermodel/EventWorkbookBuilder.java b/src/java/org/apache/poi/hssf/eventusermodel/EventWorkbookBuilder.java
index f55189ea7d..165db0e8fd 100644
--- a/src/java/org/apache/poi/hssf/eventusermodel/EventWorkbookBuilder.java
+++ b/src/java/org/apache/poi/hssf/eventusermodel/EventWorkbookBuilder.java
@@ -17,6 +17,7 @@
 package org.apache.poi.hssf.eventusermodel;
 
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
 
 import org.apache.poi.hssf.model.HSSFFormulaParser;
@@ -69,9 +70,7 @@ public class EventWorkbookBuilder {
 
 		// Core Workbook records go first
 		if(bounds != null) {
-			for (BoundSheetRecord bound : bounds) {
-				wbRecords.add(bound);
-			}
+			Collections.addAll(wbRecords, bounds);
 		}
 		if(sst != null) {
 			wbRecords.add(sst);
@@ -82,9 +81,7 @@ public class EventWorkbookBuilder {
 		if(externs != null) {
 			wbRecords.add(SupBookRecord.createInternalReferences(
 					(short)externs.length));
-			for (ExternSheetRecord extern : externs) {
-				wbRecords.add(extern);
-			}
+			Collections.addAll(wbRecords, externs);
 		}
 
 		// Finally we need an EoF record
@@ -125,12 +122,12 @@ public class EventWorkbookBuilder {
 
 		public BoundSheetRecord[] getBoundSheetRecords() {
 			return boundSheetRecords.toArray(
-					new BoundSheetRecord[boundSheetRecords.size()]
+					new BoundSheetRecord[0]
 			);
 		}
 		public ExternSheetRecord[] getExternSheetRecords() {
 			return externSheetRecords.toArray(
-					new ExternSheetRecord[externSheetRecords.size()]
+					new ExternSheetRecord[0]
 			);
 		}
 		public SSTRecord getSSTRecord() {
diff --git a/src/java/org/apache/poi/hssf/eventusermodel/HSSFRequest.java b/src/java/org/apache/poi/hssf/eventusermodel/HSSFRequest.java
index 62c656ed08..1aca412806 100644
--- a/src/java/org/apache/poi/hssf/eventusermodel/HSSFRequest.java
+++ b/src/java/org/apache/poi/hssf/eventusermodel/HSSFRequest.java
@@ -55,12 +55,9 @@ public class HSSFRequest {
 	 *        for example req.addListener(myListener, BOFRecord.sid)
 	 */
 	public void addListener(HSSFListener lsnr, short sid) {
-		List<HSSFListener> list = _records.get(Short.valueOf(sid));
+		List<HSSFListener> list = _records.computeIfAbsent(Short.valueOf(sid), k -> new ArrayList<>(1));
 
-		if (list == null) {
-			list = new ArrayList<>(1); // probably most people will use one listener
-			_records.put(Short.valueOf(sid), list);
-		}
+		// probably most people will use one listener
 		list.add(lsnr);
 	}
 
diff --git a/src/java/org/apache/poi/hssf/record/ExtSSTRecord.java b/src/java/org/apache/poi/hssf/record/ExtSSTRecord.java
index e0b975d088..2ce2810e62 100644
--- a/src/java/org/apache/poi/hssf/record/ExtSSTRecord.java
+++ b/src/java/org/apache/poi/hssf/record/ExtSSTRecord.java
@@ -103,7 +103,7 @@ public final class ExtSSTRecord extends ContinuableRecord {
                 in.nextRecord();
             }
         }
-        _sstInfos = lst.toArray(new InfoSubRecord[lst.size()]);
+        _sstInfos = lst.toArray(new InfoSubRecord[0]);
     }
 
     public void setNumStringsPerBucket(short numStrings) {
diff --git a/src/java/org/apache/poi/hssf/record/GroupMarkerSubRecord.java b/src/java/org/apache/poi/hssf/record/GroupMarkerSubRecord.java
index 575ed7a5af..47395f58bb 100644
--- a/src/java/org/apache/poi/hssf/record/GroupMarkerSubRecord.java
+++ b/src/java/org/apache/poi/hssf/record/GroupMarkerSubRecord.java
@@ -77,8 +77,7 @@ public final class GroupMarkerSubRecord extends SubRecord implements Cloneable {
     public GroupMarkerSubRecord clone() {
         GroupMarkerSubRecord rec = new GroupMarkerSubRecord();
         rec.reserved = new byte[reserved.length];
-        for ( int i = 0; i < reserved.length; i++ )
-            rec.reserved[i] = reserved[i];
+        System.arraycopy(reserved, 0, rec.reserved, 0, reserved.length);
         return rec;
     }
 }
diff --git a/src/java/org/apache/poi/hssf/record/HyperlinkRecord.java b/src/java/org/apache/poi/hssf/record/HyperlinkRecord.java
index 7f8b345275..e4454bcf66 100644
--- a/src/java/org/apache/poi/hssf/record/HyperlinkRecord.java
+++ b/src/java/org/apache/poi/hssf/record/HyperlinkRecord.java
@@ -159,9 +159,7 @@ public final class HyperlinkRecord extends StandardRecord implements Cloneable {
 			int d0 = (parseShort(cc, 0) << 16) + (parseShort(cc, 4) << 0);
 			int d1 = parseShort(cc, 9);
 			int d2 = parseShort(cc, 14);
-			for (int i = 23; i > 19; i--) {
-				cc[i] = cc[i - 1];
-			}
+            System.arraycopy(cc, 19, cc, 20, 4);
 			long d3 = parseLELong(cc, 20);
 
 			return new GUID(d0, d1, d2, d3);
diff --git a/src/java/org/apache/poi/hssf/record/PaletteRecord.java b/src/java/org/apache/poi/hssf/record/PaletteRecord.java
index 162c67c514..9ec1c4708b 100644
--- a/src/java/org/apache/poi/hssf/record/PaletteRecord.java
+++ b/src/java/org/apache/poi/hssf/record/PaletteRecord.java
@@ -18,6 +18,7 @@
 package org.apache.poi.hssf.record;
 
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
 
 import org.apache.poi.util.LittleEndianOutput;
@@ -40,9 +41,7 @@ public final class PaletteRecord extends StandardRecord {
     public PaletteRecord() {
       PColor[] defaultPalette = createDefaultPalette();
       _colors    = new ArrayList<>(defaultPalette.length);
-      for (PColor element : defaultPalette) {
-        _colors.add(element);
-      }
+      Collections.addAll(_colors, defaultPalette);
     }
 
     public PaletteRecord(RecordInputStream in) {
diff --git a/src/java/org/apache/poi/hssf/record/aggregates/RowRecordsAggregate.java b/src/java/org/apache/poi/hssf/record/aggregates/RowRecordsAggregate.java
index e32a74ba42..dc238a9625 100644
--- a/src/java/org/apache/poi/hssf/record/aggregates/RowRecordsAggregate.java
+++ b/src/java/org/apache/poi/hssf/record/aggregates/RowRecordsAggregate.java
@@ -195,7 +195,7 @@ public final class RowRecordsAggregate extends RecordAggregate {
         int startIndex = block * DBCellRecord.BLOCK_SIZE;
 
         if (_rowRecordValues == null) {
-            _rowRecordValues = _rowRecords.values().toArray(new RowRecord[_rowRecords.size()]);
+            _rowRecordValues = _rowRecords.values().toArray(new RowRecord[0]);
         }
 
         try {
@@ -212,7 +212,7 @@ public final class RowRecordsAggregate extends RecordAggregate {
             endIndex = _rowRecords.size()-1;
 
         if (_rowRecordValues == null){
-            _rowRecordValues = _rowRecords.values().toArray(new RowRecord[_rowRecords.size()]);
+            _rowRecordValues = _rowRecords.values().toArray(new RowRecord[0]);
         }
 
         try {
diff --git a/src/java/org/apache/poi/hssf/usermodel/HSSFChart.java b/src/java/org/apache/poi/hssf/usermodel/HSSFChart.java
index f91781dc64..c08511fa46 100644
--- a/src/java/org/apache/poi/hssf/usermodel/HSSFChart.java
+++ b/src/java/org/apache/poi/hssf/usermodel/HSSFChart.java
@@ -273,7 +273,7 @@ public final class HSSFChart {
 			}
 		}
 
-		return charts.toArray( new HSSFChart[charts.size()] );
+		return charts.toArray(new HSSFChart[0]);
 	}
 
 	/** Get the X offset of the chart */
@@ -298,7 +298,7 @@ public final class HSSFChart {
 	 * Returns the series of the chart
 	 */
 	public HSSFSeries[] getSeries() {
-		return series.toArray(new HSSFSeries[series.size()]);
+		return series.toArray(new HSSFSeries[0]);
 	}
 
 	/**
@@ -1153,7 +1153,7 @@ public final class HSSFChart {
 				}
 			}
 			
-			linkedDataRecord.setFormulaOfLink(ptgList.toArray(new Ptg[ptgList.size()]));
+			linkedDataRecord.setFormulaOfLink(ptgList.toArray(new Ptg[0]));
 			
 			return rowCount * colCount;
 		}
diff --git a/src/java/org/apache/poi/poifs/filesystem/POIFSDocumentPath.java b/src/java/org/apache/poi/poifs/filesystem/POIFSDocumentPath.java
index 7c74d47871..80db4b3c48 100644
--- a/src/java/org/apache/poi/poifs/filesystem/POIFSDocumentPath.java
+++ b/src/java/org/apache/poi/poifs/filesystem/POIFSDocumentPath.java
@@ -122,10 +122,7 @@ public class POIFSDocumentPath
             this.components =
                 new String[ path.components.length + components.length ];
         }
-        for (int j = 0; j < path.components.length; j++)
-        {
-            this.components[ j ] = path.components[ j ];
-        }
+        System.arraycopy(path.components, 0, this.components, 0, path.components.length);
         if (components != null)
         {
             for (int j = 0; j < components.length; j++)
diff --git a/src/java/org/apache/poi/ss/format/CellFormat.java b/src/java/org/apache/poi/ss/format/CellFormat.java
index 6c218d55b1..8d4d82fab9 100644
--- a/src/java/org/apache/poi/ss/format/CellFormat.java
+++ b/src/java/org/apache/poi/ss/format/CellFormat.java
@@ -154,11 +154,7 @@ public class CellFormat {
      * @return A {@link CellFormat} that applies the given format.
      */
     public static synchronized CellFormat getInstance(Locale locale, String format) {
-        Map<String, CellFormat> formatMap = formatCache.get(locale);
-        if (formatMap == null) {
-            formatMap = new WeakHashMap<>();
-            formatCache.put(locale, formatMap);
-        }
+        Map<String, CellFormat> formatMap = formatCache.computeIfAbsent(locale, k -> new WeakHashMap<>());
         CellFormat fmt = formatMap.get(format);
         if (fmt == null) {
             if (format.equals("General") || format.equals("@"))
diff --git a/src/java/org/apache/poi/ss/formula/CollaboratingWorkbooksEnvironment.java b/src/java/org/apache/poi/ss/formula/CollaboratingWorkbooksEnvironment.java
index bfd1f4e35b..57b13bf426 100644
--- a/src/java/org/apache/poi/ss/formula/CollaboratingWorkbooksEnvironment.java
+++ b/src/java/org/apache/poi/ss/formula/CollaboratingWorkbooksEnvironment.java
@@ -71,7 +71,7 @@ public final class CollaboratingWorkbooksEnvironment {
             throw new IllegalArgumentException("Must provide at least one collaborating worbook");
         }
         WorkbookEvaluator[] evaluators = 
-                evaluatorsByName.values().toArray(new WorkbookEvaluator[evaluatorsByName.size()]); 
+                evaluatorsByName.values().toArray(new WorkbookEvaluator[0]); 
         new CollaboratingWorkbooksEnvironment(evaluatorsByName, evaluators);
     }
     public static void setupFormulaEvaluator(Map<String,FormulaEvaluator> evaluators) {
diff --git a/src/java/org/apache/poi/ss/formula/FormulaCellCacheEntry.java b/src/java/org/apache/poi/ss/formula/FormulaCellCacheEntry.java
index 63142e88b6..9dbb7248c8 100644
--- a/src/java/org/apache/poi/ss/formula/FormulaCellCacheEntry.java
+++ b/src/java/org/apache/poi/ss/formula/FormulaCellCacheEntry.java
@@ -17,6 +17,7 @@
 
 package org.apache.poi.ss.formula;
 
+import java.util.Arrays;
 import java.util.Collections;
 import java.util.HashSet;
 import java.util.Set;
@@ -94,9 +95,7 @@ final class FormulaCellCacheEntry extends CellCacheEntry {
 			usedSet = Collections.emptySet();
 		} else {
 			usedSet = new HashSet<>(nUsed * 3 / 2);
-			for (int i = 0; i < nUsed; i++) {
-				usedSet.add(usedCells[i]);
-			}
+			usedSet.addAll(Arrays.asList(usedCells).subList(0, nUsed));
 		}
 		for (int i = 0; i < nPrevUsed; i++) {
 			CellCacheEntry prevUsed = prevUsedCells[i];
@@ -121,4 +120,4 @@ final class FormulaCellCacheEntry extends CellCacheEntry {
 			}
 		}
 	}
-}
\ No newline at end of file
+}
diff --git a/src/java/org/apache/poi/ss/formula/functions/Subtotal.java b/src/java/org/apache/poi/ss/formula/functions/Subtotal.java
index 8727353ae2..8d7084be83 100644
--- a/src/java/org/apache/poi/ss/formula/functions/Subtotal.java
+++ b/src/java/org/apache/poi/ss/formula/functions/Subtotal.java
@@ -141,6 +141,6 @@ public class Subtotal implements Function {
 			}
 		}
 
-		return innerFunc.evaluate(list.toArray(new ValueEval[list.size()]), srcRowIndex, srcColumnIndex);
+		return innerFunc.evaluate(list.toArray(new ValueEval[0]), srcRowIndex, srcColumnIndex);
 	}
 }
diff --git a/src/java/org/apache/poi/ss/formula/functions/Trend.java b/src/java/org/apache/poi/ss/formula/functions/Trend.java
index ec10277d7e..a6c3709344 100644
--- a/src/java/org/apache/poi/ss/formula/functions/Trend.java
+++ b/src/java/org/apache/poi/ss/formula/functions/Trend.java
@@ -149,9 +149,7 @@ public final class Trend implements Function {
         }
         double[] oneD = new double[twoD.length * twoD[0].length];
         for (int i = 0; i < twoD.length; i++) {
-            for (int j = 0; j < twoD[0].length; j++) {
-                oneD[i * twoD[0].length + j] = twoD[i][j];
-            }
+            System.arraycopy(twoD[i], 0, oneD, i * twoD[0].length + 0, twoD[0].length);
         }
         return oneD;
     }
diff --git a/src/java/org/apache/poi/ss/util/CellRangeUtil.java b/src/java/org/apache/poi/ss/util/CellRangeUtil.java
index 8c40a4d63a..3b8b5251d4 100644
--- a/src/java/org/apache/poi/ss/util/CellRangeUtil.java
+++ b/src/java/org/apache/poi/ss/util/CellRangeUtil.java
@@ -18,6 +18,7 @@
 package org.apache.poi.ss.util;
 
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
 
 /**
@@ -173,9 +174,7 @@ public final class CellRangeUtil {
     }
     private static List<CellRangeAddress> toList(CellRangeAddress[] temp) {
         List<CellRangeAddress> result = new ArrayList<>(temp.length);
-        for (CellRangeAddress range : temp) {
-            result.add(range);
-        }
+        Collections.addAll(result, temp);
         return result;
     }
 
diff --git a/src/java/org/apache/poi/util/HexRead.java b/src/java/org/apache/poi/util/HexRead.java
index 1db930f25d..0acaef6e27 100644
--- a/src/java/org/apache/poi/util/HexRead.java
+++ b/src/java/org/apache/poi/util/HexRead.java
@@ -125,7 +125,7 @@ public class HexRead {
                 }
             }
         }
-        Byte[] polished = bytes.toArray(new Byte[bytes.size()]);
+        Byte[] polished = bytes.toArray(new Byte[0]);
         byte[] rval = new byte[polished.length];
         for ( int j = 0; j < polished.length; j++ ) {
             rval[j] = polished[j].byteValue();