LUCENE-5324: AnalyzerWrapper.get(PositionIncrement|Offset)Gap can now be overridden.

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1538557 13f79535-47bb-0310-9956-ffa450edef68

lucene/CHANGES.txt

@@ -212,6 +212,9 @@ API Changes:
 * LUCENE-5321: Remove Facet42DocValuesFormat. Use DirectDocValuesFormat if you
   want to load the category list into memory. (Shai Erera, Mike McCandless)
 
+* LUCENE-5324: AnalyzerWrapper.getPositionIncrementGap and getOffsetGap can now
+  be overridden. (Adrien Grand)
+
 Optimizations
 
 * LUCENE-5225: The ToParentBlockJoinQuery only keeps tracks of the the child

lucene/core/src/java/org/apache/lucene/analysis/AnalyzerWrapper.java

@@ -103,12 +103,12 @@ public abstract class AnalyzerWrapper extends Analyzer {
   }
 
   @Override
-  public final int getPositionIncrementGap(String fieldName) {
+  public int getPositionIncrementGap(String fieldName) {
     return getWrappedAnalyzer(fieldName).getPositionIncrementGap(fieldName);
   }
 
   @Override
-  public final int getOffsetGap(String fieldName) {
+  public int getOffsetGap(String fieldName) {
     return getWrappedAnalyzer(fieldName).getOffsetGap(fieldName);
   }
 

lucene/core/src/test/org/apache/lucene/analysis/TestMockAnalyzer.java

@@ -5,6 +5,17 @@ import java.io.StringReader;
 import java.util.Arrays;
 import java.util.Random;
 
+import org.apache.lucene.document.Document;
+import org.apache.lucene.document.Field;
+import org.apache.lucene.document.FieldType;
+import org.apache.lucene.index.AtomicReader;
+import org.apache.lucene.index.DocsAndPositionsEnum;
+import org.apache.lucene.index.FieldInfo.IndexOptions;
+import org.apache.lucene.index.Fields;
+import org.apache.lucene.index.RandomIndexWriter;
+import org.apache.lucene.index.Terms;
+import org.apache.lucene.index.TermsEnum;
+import org.apache.lucene.util.BytesRef;
 import org.apache.lucene.util._TestUtil;
 import org.apache.lucene.util.automaton.Automaton;
 import org.apache.lucene.util.automaton.AutomatonTestUtil;
@@ -276,4 +287,53 @@ public class TestMockAnalyzer extends BaseTokenStreamTestCase {
     
     checkOneTerm(a, "abc", "aabc");
   }
+
+  public void testChangeGaps() throws Exception {
+    // LUCENE-5324: check that it is possible to change the wrapper's gaps
+    final int positionGap = random().nextInt(1000);
+    final int offsetGap = random().nextInt(1000);
+    final Analyzer delegate = new MockAnalyzer(random());
+    final Analyzer a = new AnalyzerWrapper(delegate.getReuseStrategy()) {      
+      @Override
+      protected Analyzer getWrappedAnalyzer(String fieldName) {
+        return delegate;
+      }
+      @Override
+      public int getPositionIncrementGap(String fieldName) {
+        return positionGap;
+      }
+      @Override
+      public int getOffsetGap(String fieldName) {
+        return offsetGap;
+      }
+    };
+
+    final RandomIndexWriter writer = new RandomIndexWriter(random(), newDirectory());
+    final Document doc = new Document();
+    final FieldType ft = new FieldType();
+    ft.setIndexed(true);
+    ft.setTokenized(true);
+    ft.setIndexOptions(IndexOptions.DOCS_AND_FREQS_AND_POSITIONS_AND_OFFSETS);
+    doc.add(new Field("f", "a", ft));
+    doc.add(new Field("f", "a", ft));
+    writer.addDocument(doc, a);
+    final AtomicReader reader = getOnlySegmentReader(writer.getReader());
+    final Fields fields = reader.fields();
+    final Terms terms = fields.terms("f");
+    final TermsEnum te = terms.iterator(null);
+    assertEquals(new BytesRef("a"), te.next());
+    final DocsAndPositionsEnum dpe = te.docsAndPositions(null, null);
+    assertEquals(0, dpe.nextDoc());
+    assertEquals(2, dpe.freq());
+    assertEquals(0, dpe.nextPosition());
+    assertEquals(0, dpe.startOffset());
+    final int endOffset = dpe.endOffset();
+    assertEquals(1 + positionGap, dpe.nextPosition());
+    assertEquals(1 + endOffset + offsetGap, dpe.endOffset());
+    assertEquals(null, te.next());
+    reader.close();
+    writer.close();
+    writer.w.getDirectory().close();
+  }
+
 }