ODFTOOLKIT-187: fix results of PuzzlePiece.extractPuzzlePieces()

This created nondeterministic and wrong results, somewhere in
reduceAttributes().

The reason appears to be that there are ordered containers like a
TreeSet<PuzzlePiece> in uniteDefinitionsWithEqualContent() involved
and the PuzzlePiece.compareTo() has a problem with overflow, so it
sometimes returns wrong results and then the TreeSet will be wrongly
sorted and it can't find some elements.

Just compare the integers properly and the result is deterministic.

(cherry picked from commit 335bab8)

Author: mistmist

generator/schema2template/src/main/java/schema2template/model/PuzzlePiece.java

@@ -192,7 +192,7 @@ public int compareTo(PuzzlePiece o) {
     if (retval != 0) {
       return retval;
     }
-    return hashCode() - o.hashCode();
+    return Integer.compare(hashCode(), o.hashCode());
   }
 
   /*

generator/schema2template/src/test/java/schema2template/example/odf/PuzzlePieceTest.java

@@ -35,7 +35,6 @@
 import java.util.logging.Level;
 import java.util.logging.Logger;
 import org.junit.Assert;
-import org.junit.Ignore;
 import org.junit.Test;
 import schema2template.model.MSVExpressionIterator;
 import schema2template.model.PuzzlePiece;
@@ -54,7 +53,7 @@ public class PuzzlePieceTest {
   private static final String OUTPUT_REF_ODF12 =
       TEST_REFERENCE_DIR + File.separator + "odf12-msvtree.ref";
   private static final int ODF12_ELEMENT_DUPLICATES = 7;
-  private static final int ODF12_ATTRIBUTE_DUPLICATES = 134;
+  private static final int ODF12_ATTRIBUTE_DUPLICATES = 116;
 
   /**
    * Test: Use the MSV
@@ -155,7 +154,6 @@ private String readFileAsString(String filePath) throws java.io.IOException {
    * extract PuzzlePieces out of a XML schema
    */
   @Test
-  @Ignore // due to issue https://issues.apache.org/jira/browse/ODFTOOLKIT-180
   public void testExtractPuzzlePieces() {
     try {
       PuzzlePieceSet allElements_ODF11 = new PuzzlePieceSet();
@@ -189,7 +187,6 @@ public void testExtractPuzzlePieces() {
    * extract PuzzlePieces out of a XML schema
    */
   @Test
-  @Ignore
   public void testExtractPuzzlePiecesWithDuplicates() {
     try {
       PuzzlePieceSet allElements_ODF12 = new PuzzlePieceSet();