- Applied patches from http://nagoya.apache.org/bugzilla/show_bug.cgi?id=14900

All unit tests still pass.
PR:            14900
Obtained from:
Submitted by:  Peter Mularien
Reviewed by:   Otis


git-svn-id: https://svn.apache.org/repos/asf/lucene/java/trunk@149910 13f79535-47bb-0310-9956-ffa450edef68

src/java/org/apache/lucene/index/IndexReader.java

@@ -56,6 +56,8 @@ package org.apache.lucene.index;
 
 import java.io.IOException;
 import java.io.File;
+import java.util.Collection;
+
 import org.apache.lucene.store.Directory;
 import org.apache.lucene.store.FSDirectory;
 import org.apache.lucene.store.Lock;
@@ -302,6 +304,14 @@ public abstract class IndexReader {
     }
   }
 
+    /**
+     * Return a list of all unique field names which exist in the index pointed to by
+     * this IndexReader.
+     * @return Collection of Strings indicating the names of the fields
+     * @throws IOException if there is a problem with accessing the index
+     */
+    public abstract Collection getFieldNames() throws IOException;
+
   /**
    * Returns <code>true</code> iff the index in the named directory is
    * currently locked.

src/java/org/apache/lucene/index/SegmentReader.java

@@ -55,15 +55,17 @@ package org.apache.lucene.index;
  */
 
 import java.io.IOException;
-import java.util.Hashtable;
+import java.util.Collection;
 import java.util.Enumeration;
+import java.util.HashSet;
+import java.util.Hashtable;
+import java.util.Set;
 import java.util.Vector;
 
-import org.apache.lucene.util.BitVector;
-import org.apache.lucene.store.Directory;
-import org.apache.lucene.store.Lock;
-import org.apache.lucene.store.InputStream;
 import org.apache.lucene.document.Document;
+import org.apache.lucene.store.InputStream;
+import org.apache.lucene.store.Lock;
+import org.apache.lucene.util.BitVector;
 
 final class SegmentReader extends IndexReader {
   private boolean closeDirectory = false;
@@ -73,7 +75,7 @@ final class SegmentReader extends IndexReader {
   private FieldsReader fieldsReader;
 
   TermInfosReader tis;
-  
+
   BitVector deletedDocs = null;
   private boolean deletedDocsDirty = false;
 
@@ -113,7 +115,7 @@ final class SegmentReader extends IndexReader {
     proxStream = directory.openFile(segment + ".prx");
     openNorms();
   }
-  
+
   final synchronized void doClose() throws IOException {
     if (deletedDocsDirty) {
       synchronized (directory) {		  // in- & inter-process sync
@@ -271,4 +273,15 @@ final class SegmentReader extends IndexReader {
       }
     }
   }
+
+    // javadoc inherited
+    public Collection getFieldNames() throws IOException {
+        // maintain a unique set of field names
+        Set fieldSet = new HashSet();
+        for (int i = 0; i < fieldInfos.size(); i++) {
+            FieldInfo fi = fieldInfos.fieldInfo(i);
+            fieldSet.add(fi.name);
+        }
+        return fieldSet;
+    }
 }

src/java/org/apache/lucene/index/SegmentsReader.java

@@ -55,10 +55,14 @@ package org.apache.lucene.index;
  */
 
 import java.io.IOException;
+import java.util.Collection;
+import java.util.HashSet;
 import java.util.Hashtable;
+import java.util.Iterator;
+import java.util.Set;
 
-import org.apache.lucene.store.Directory;
 import org.apache.lucene.document.Document;
+import org.apache.lucene.store.Directory;
 
 /**
  * FIXME: Describe class <code>SegmentsReader</code> here.
@@ -174,6 +178,22 @@ final class SegmentsReader extends IndexReader
     for (int i = 0; i < readers.length; i++)
       readers[i].close();
   }
+
+    // javadoc inherited
+    public Collection getFieldNames() throws IOException {
+        // maintain a unique set of field names
+        Set fieldSet = new HashSet();
+        for (int i = 0; i < readers.length; i++) {
+            SegmentReader reader = readers[i];
+            Collection names = reader.getFieldNames();
+            // iterate through the field names and add them to the set
+            for (Iterator iterator = names.iterator(); iterator.hasNext();) {
+                String s = (String) iterator.next();
+                fieldSet.add(s);
+            }
+        }
+        return fieldSet;
+    }
 }
 
 class SegmentsTermEnum extends TermEnum {

src/test/org/apache/lucene/index/TestIndexReader.java

@@ -0,0 +1,132 @@
+package org.apache.lucene.index;
+
+import junit.framework.TestCase;
+import org.apache.lucene.store.RAMDirectory;
+import org.apache.lucene.analysis.standard.StandardAnalyzer;
+import org.apache.lucene.document.Document;
+import org.apache.lucene.document.Field;
+
+import java.util.Collection;
+import java.io.IOException;
+
+/* ====================================================================
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2003 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution,
+ *    if any, must include the following acknowledgment:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowledgment may appear in the software itself,
+ *    if and wherever such third-party acknowledgments normally appear.
+ *
+ * 4. The names "Apache" and "Apache Software Foundation" and
+ *    "Apache Lucene" must not be used to endorse or promote products
+ *    derived from this software without prior written permission. For
+ *    written permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache",
+ *    "Apache Lucene", nor may "Apache" appear in their name, without
+ *    prior written permission of the Apache Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+public class TestIndexReader extends TestCase
+{
+    /**
+     * Tests the IndexReader.getFieldNames implementation
+     * @throws Exception on error
+     */
+    public void testGetFieldNames() throws Exception
+    {
+        RAMDirectory d = new RAMDirectory();
+        // set up writer
+        IndexWriter writer = new IndexWriter(d, new StandardAnalyzer(), true);
+        addDocumentWithFields(writer);
+        writer.close();
+        // set up reader
+        IndexReader reader = IndexReader.open(d);
+        Collection fieldNames = reader.getFieldNames();
+        assertTrue(fieldNames.contains("keyword"));
+        assertTrue(fieldNames.contains("text"));
+        assertTrue(fieldNames.contains("unindexed"));
+        assertTrue(fieldNames.contains("unstored"));
+        // add more documents
+        writer = new IndexWriter(d, new StandardAnalyzer(), false);
+        // want to get some more segments here
+        for (int i=0;i<5*writer.mergeFactor;i++)
+        {
+            addDocumentWithFields(writer);
+        }
+        // new fields are in some different segments (we hope)
+        for (int i=0;i<5*writer.mergeFactor;i++)
+        {
+            addDocumentWithDifferentFields(writer);
+        }
+        writer.close();
+        // verify fields again
+        reader = IndexReader.open(d);
+        fieldNames = reader.getFieldNames();
+        assertTrue(fieldNames.contains("keyword"));
+        assertTrue(fieldNames.contains("text"));
+        assertTrue(fieldNames.contains("unindexed"));
+        assertTrue(fieldNames.contains("unstored"));
+        assertTrue(fieldNames.contains("keyword2"));
+        assertTrue(fieldNames.contains("text2"));
+        assertTrue(fieldNames.contains("unindexed2"));
+        assertTrue(fieldNames.contains("unstored2"));
+    }
+
+    private void addDocumentWithFields(IndexWriter writer) throws IOException
+    {
+        Document doc = new Document();
+        doc.add(Field.Keyword("keyword","test1"));
+        doc.add(Field.Text("text","test1"));
+        doc.add(Field.UnIndexed("unindexed","test1"));
+        doc.add(Field.UnStored("unstored","test1"));
+        writer.addDocument(doc);
+    }
+
+    private void addDocumentWithDifferentFields(IndexWriter writer) throws IOException
+    {
+        Document doc = new Document();
+        doc.add(Field.Keyword("keyword2","test1"));
+        doc.add(Field.Text("text2","test1"));
+        doc.add(Field.UnIndexed("unindexed2","test1"));
+        doc.add(Field.UnStored("unstored2","test1"));
+        writer.addDocument(doc);
+    }
+}
+