فهرست منبع

MAPREDUCE-2. Fixes a bug in KeyFieldBasedPartitioner in handling empty keys. Contributed by Amar Kamat.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-0.20@788632 13f79535-47bb-0310-9956-ffa450edef68
Sharad Agarwal 16 سال پیش
والد
کامیت
5d76320ca0

+ 3 - 0
CHANGES.txt

@@ -144,6 +144,9 @@ Release 0.20.1 - Unreleased
     lack of quota. Allow quota to be set even if the limit is lower than
     lack of quota. Allow quota to be set even if the limit is lower than
     current consumption. (Boris Shkolnik via rangadi)
     current consumption. (Boris Shkolnik via rangadi)
 
 
+    MAPREDUCE-2. Fixes a bug in KeyFieldBasedPartitioner in handling empty
+    keys. (Amar Kamat via sharad)
+
 Release 0.20.0 - 2009-04-15
 Release 0.20.0 - 2009-04-15
 
 
   INCOMPATIBLE CHANGES
   INCOMPATIBLE CHANGES

+ 9 - 0
src/mapred/org/apache/hadoop/mapred/lib/KeyFieldBasedPartitioner.java

@@ -76,12 +76,21 @@ public class KeyFieldBasedPartitioner<K2, V2> implements Partitioner<K2, V2> {
       throw new RuntimeException("The current system does not " +
       throw new RuntimeException("The current system does not " +
           "support UTF-8 encoding!", e);
           "support UTF-8 encoding!", e);
     }
     }
+    // return 0 if the key is empty
+    if (keyBytes.length == 0) {
+      return 0;
+    }
+    
     int []lengthIndicesFirst = keyFieldHelper.getWordLengths(keyBytes, 0, 
     int []lengthIndicesFirst = keyFieldHelper.getWordLengths(keyBytes, 0, 
         keyBytes.length);
         keyBytes.length);
     int currentHash = 0;
     int currentHash = 0;
     for (KeyDescription keySpec : allKeySpecs) {
     for (KeyDescription keySpec : allKeySpecs) {
       int startChar = keyFieldHelper.getStartOffset(keyBytes, 0, keyBytes.length, 
       int startChar = keyFieldHelper.getStartOffset(keyBytes, 0, keyBytes.length, 
           lengthIndicesFirst, keySpec);
           lengthIndicesFirst, keySpec);
+       // no key found! continue
+      if (startChar < 0) {
+        continue;
+      }
       int endChar = keyFieldHelper.getEndOffset(keyBytes, 0, keyBytes.length, 
       int endChar = keyFieldHelper.getEndOffset(keyBytes, 0, keyBytes.length, 
           lengthIndicesFirst, keySpec);
           lengthIndicesFirst, keySpec);
       currentHash = hashCode(keyBytes, startChar, endChar, 
       currentHash = hashCode(keyBytes, startChar, endChar, 

+ 40 - 0
src/test/org/apache/hadoop/mapred/lib/TestKeyFieldBasedPartitioner.java

@@ -0,0 +1,40 @@
+/**
+ * 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.mapred.lib;
+
+import org.apache.hadoop.io.Text;
+import org.apache.hadoop.mapred.JobConf;
+import org.apache.hadoop.mapred.lib.KeyFieldBasedPartitioner;
+
+import junit.framework.TestCase;
+
+public class TestKeyFieldBasedPartitioner extends TestCase {
+
+  /**
+   * Test is key-field-based partitioned works with empty key.
+   */
+  public void testEmptyKey() throws Exception {
+    KeyFieldBasedPartitioner<Text, Text> kfbp = 
+      new KeyFieldBasedPartitioner<Text, Text>();
+    JobConf conf = new JobConf();
+    conf.setInt("num.key.fields.for.partition", 10);
+    kfbp.configure(conf);
+    assertEquals("Empty key should map to 0th partition", 
+                 0, kfbp.getPartition(new Text(), new Text(), 10));
+  }
+}