HADOOP-6934. svn merge -c 991821 from trunk.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-0.21@997406 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -10,6 +10,11 @@ Release 0.21.1 - Unreleased
     HADOOP-6833. IPC leaks call parameters when exceptions thrown.
     (Todd Lipcon via Eli Collins)
 
+  IMPROVEMENTS
+
+    HADOOP-6934. Test for ByteWritable comparator.
+    (Johannes Zillmann via Eli Collins)
+
 Release 0.21.0 - 2010-08-13
 
   INCOMPATIBLE CHANGES

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

@@ -0,0 +1,53 @@
+/**
+ * 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 org.junit.Test;
+import static org.junit.Assert.*;
+
+public class TestBooleanWritable {
+
+  @Test
+  public void testCompareUnequalWritables() 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;
+  }
+}