HADOOP-6928. Fix BooleanWritable comparator in 0.20. Contributed by Owen O'Malley and Johannes Zillmann.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-0.20@991790 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -50,6 +50,9 @@ Release 0.20.3 - Unreleased
     HADOOP-6833. IPC leaks call parameters when exceptions thrown.
     (Todd Lipcon via Eli Collins)
 
+    HADOOP-6928. Fix BooleanWritable comparator in 0.20.
+    (Owen O'Malley and Johannes Zillmann via Eli Collins)
+
   IMPROVEMENTS
 
     MAPREDUCE-1407. Update javadoc in mapreduce.{Mapper,Reducer} to match

src/core/org/apache/hadoop/io/BooleanWritable.java

@@ -100,9 +100,7 @@ public class BooleanWritable implements WritableComparable {
 
     public int compare(byte[] b1, int s1, int l1,
                        byte[] b2, int s2, int l2) {
-      boolean a = (readInt(b1, s1) == 1) ? true : false;
-      boolean b = (readInt(b2, s2) == 1) ? true : false;
-      return ((a == b) ? 0 : (a == false) ? -1 : 1);
+      return compareBytes(b1, s1, l1, b2, s2, l2);
     }
   }
 

src/test/org/apache/hadoop/io/TestBooleanWritable.java

@@ -0,0 +1,52 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.hadoop.io;
+
+import java.io.IOException;
+
+import junit.framework.TestCase;
+
+public class TestBooleanWritable extends TestCase {
+
+  public void testComparator() throws Exception {
+    DataOutputBuffer bTrue = writeWritable(new BooleanWritable(true));
+    DataOutputBuffer bFalse = writeWritable(new BooleanWritable(false));
+    WritableComparator writableComparator = WritableComparator
+	.get(BooleanWritable.class);
+
+    assertEquals(0, compare(writableComparator, bTrue, bTrue));
+    assertEquals(0, compare(writableComparator, bFalse, bFalse));
+    assertEquals(1, compare(writableComparator, bTrue, bFalse));
+    assertEquals(-1, compare(writableComparator, bFalse, bTrue));
+  }
+
+  private int compare(WritableComparator writableComparator,
+      DataOutputBuffer buf1, DataOutputBuffer buf2) {
+    return writableComparator.compare(buf1.getData(), 0, buf1.size(), buf2
+	.getData(), 0, buf2.size());
+  }
+
+  protected DataOutputBuffer writeWritable(Writable writable)
+      throws IOException {
+    DataOutputBuffer out = new DataOutputBuffer(1024);
+    writable.write(out);
+    out.flush();
+    return out;
+  }
+
+}