LUCENE-5153: Allow wrapping Reader from AnalyzerWrapper

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1508622 13f79535-47bb-0310-9956-ffa450edef68

lucene/CHANGES.txt

@@ -84,6 +84,9 @@ New features
   FacetRequest which implements createFacetsAggregator and was indexed
   using the taxonomy index. (Shai Erera)
 
+* LUCENE-5153: AnalyzerWrapper.wrapReader allows wrapping the Reader given to 
+  inputReader. (Shai Erera)
+   
 Bug Fixes
 
 * LUCENE-5116: IndexWriter.addIndexes(IndexReader...) should drop empty (or all

lucene/analysis/common/src/java/org/apache/lucene/analysis/miscellaneous/PerFieldAnalyzerWrapper.java

@@ -83,11 +83,6 @@ public final class PerFieldAnalyzerWrapper extends AnalyzerWrapper {
     return (analyzer != null) ? analyzer : defaultAnalyzer;
   }
 
-  @Override
-  protected TokenStreamComponents wrapComponents(String fieldName, TokenStreamComponents components) {
-    return components;
-  }
-  
   @Override
   public String toString() {
     return "PerFieldAnalyzerWrapper(" + fieldAnalyzers + ", default=" + defaultAnalyzer + ")";

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

@@ -51,16 +51,35 @@ public abstract class AnalyzerWrapper extends Analyzer {
 
   /**
    * Wraps / alters the given TokenStreamComponents, taken from the wrapped
-   * Analyzer, to form new components.  It is through this method that new
-   * TokenFilters can be added by AnalyzerWrappers.
-   *
-   *
-   * @param fieldName Name of the field which is to be analyzed
-   * @param components TokenStreamComponents taken from the wrapped Analyzer
+   * Analyzer, to form new components. It is through this method that new
+   * TokenFilters can be added by AnalyzerWrappers. By default, the given
+   * components are returned.
+   * 
+   * @param fieldName
+   *          Name of the field which is to be analyzed
+   * @param components
+   *          TokenStreamComponents taken from the wrapped Analyzer
    * @return Wrapped / altered TokenStreamComponents.
    */
-  protected abstract TokenStreamComponents wrapComponents(String fieldName, TokenStreamComponents components);
+  protected TokenStreamComponents wrapComponents(String fieldName, TokenStreamComponents components) {
+    return components;
+  }
 
+  /**
+   * Wraps / alters the given Reader. Through this method AnalyzerWrappers can
+   * implement {@link #initReader(String, Reader)}. By default, the given reader
+   * is returned.
+   * 
+   * @param fieldName
+   *          name of the field which is to be analyzed
+   * @param reader
+   *          the reader to wrap
+   * @return the wrapped reader
+   */
+  protected Reader wrapReader(String fieldName, Reader reader) {
+    return reader;
+  }
+  
   @Override
   protected final TokenStreamComponents createComponents(String fieldName, Reader aReader) {
     return wrapComponents(fieldName, getWrappedAnalyzer(fieldName).createComponents(fieldName, aReader));
@@ -78,6 +97,6 @@ public abstract class AnalyzerWrapper extends Analyzer {
 
   @Override
   public final Reader initReader(String fieldName, Reader reader) {
-    return getWrappedAnalyzer(fieldName).initReader(fieldName, reader);
+    return getWrappedAnalyzer(fieldName).initReader(fieldName, wrapReader(fieldName, reader));
   }
 }

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

@@ -1,7 +1,9 @@
 package org.apache.lucene.analysis;
 
+import java.io.Reader;
 import java.io.StringReader;
 import java.util.Arrays;
+import java.util.Random;
 
 import org.apache.lucene.util._TestUtil;
 import org.apache.lucene.util.automaton.Automaton;
@@ -128,4 +130,29 @@ public class TestMockAnalyzer extends BaseTokenStreamTestCase {
       ts.close();
     }
   }
+  
+  public void testWrapReader() throws Exception {
+    // LUCENE-5153: test that wrapping an analyzer's reader is allowed
+    final Random random = random();
+    
+    Analyzer a = new AnalyzerWrapper() {
+      
+      @Override
+      protected Reader wrapReader(String fieldName, Reader reader) {
+        return new MockCharFilter(reader, 7);
+      }
+      
+      @Override
+      protected TokenStreamComponents wrapComponents(String fieldName, TokenStreamComponents components) {
+        return components;
+      }
+      
+      @Override
+      protected Analyzer getWrappedAnalyzer(String fieldName) {
+        return new MockAnalyzer(random);
+      }
+    };
+    
+    checkOneTerm(a, "abc", "aabc");
+  }
 }

solr/core/src/java/org/apache/solr/schema/IndexSchema.java

@@ -397,10 +397,6 @@ public class IndexSchema {
       return analyzer != null ? analyzer : getDynamicFieldType(fieldName).getAnalyzer();
     }
 
-    @Override
-    protected TokenStreamComponents wrapComponents(String fieldName, TokenStreamComponents components) {
-      return components;
-    }
   }
 
   private class SolrQueryAnalyzer extends SolrIndexAnalyzer {