branch-0.23.1/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/io/TestArrayWritable.java

/**
 * 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.*;

import junit.framework.TestCase;

/** Unit tests for ArrayWritable */
public class TestArrayWritable extends TestCase {
	
  static class TextArrayWritable extends ArrayWritable {
    public TextArrayWritable() {
      super(Text.class);
    }
  }
	
  public TestArrayWritable(String name) { 
    super(name); 
  }
	
  /**
   * If valueClass is undefined, readFields should throw an exception indicating
   * that the field is null. Otherwise, readFields should succeed.	
   */
  public void testThrowUndefinedValueException() throws IOException {
    // Get a buffer containing a simple text array
    Text[] elements = {new Text("zero"), new Text("one"), new Text("two")};
    TextArrayWritable sourceArray = new TextArrayWritable();
    sourceArray.set(elements);

    // Write it to a normal output buffer
    DataOutputBuffer out = new DataOutputBuffer();
    DataInputBuffer in = new DataInputBuffer();
    sourceArray.write(out);

    // Read the output buffer with TextReadable. Since the valueClass is defined,
    // this should succeed
    TextArrayWritable destArray = new TextArrayWritable();
    in.reset(out.getData(), out.getLength());
    destArray.readFields(in);
    Writable[] destElements = destArray.get();
    assertTrue(destElements.length == elements.length);
    for (int i = 0; i < elements.length; i++) {
      assertEquals(destElements[i],elements[i]);
    }
  }
}