versionmismatchexception.java

Hadoop是一个用于运行应用程序在大型集群的廉价硬件设备上的框架。Hadoop为应用程序透明的提供了一组稳定/可靠的接口和数据运动。在 Hadoop中实现了Google的MapReduce算法

/**
 * Copyright 2005 The Apache Software Foundation
 *
 * Licensed 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;

/** Thrown by {@link VersionedWritable#readFields(DataInput)} when the
 * version of an object being read does not match the current implementation
 * version as returned by {@link VersionedWritable#getVersion()}. */
public class VersionMismatchException extends IOException {

  private byte expectedVersion;
  private byte foundVersion;

  public VersionMismatchException(byte expectedVersionIn, byte foundVersionIn){
    expectedVersion = expectedVersionIn;
    foundVersion = foundVersionIn;
  }

  /** Returns a string representation of this object. */
  public String toString(){
    return "A record version mismatch occured. Expecting v"
      + expectedVersion + ", found v" + foundVersion; 
  }
}