content: /*
   * 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 com.aliyun.odps.mapred.local.lib;
  
  import java.io.IOException;
  import java.util.Iterator;
  
  import com.aliyun.odps.data.Record;
  import com.aliyun.odps.mapred.ReducerBase;
  
  /**
   * IdentityReducer
   *
   * @author mingdi
   */
  public class IdentityReducer extends ReducerBase {
  
    private Record result = null;
  
    @Override
    public void setup(TaskContext context) throws IOException {
      result = context.createOutputRecord();
    }
  
    /**
     * Writes all keys and values directly to output.
     */
    @Override
    public void reduce(Record key, Iterator<Record> values, TaskContext context)
        throws IOException {
      result.set(0, key.get(0));
  
      while (values.hasNext()) {
        Record val = values.next();
        result.set(1, val.get(0));
        context.write(result);
      }
    }
  
  }
  
  // public class IdentityReducer<KEYIN, VALUEIN> extends Reducer<KEYIN, VALUEIN>
  // {
  // private Record result = null;
  //
  // @Override
  // protected void setup(ReduceContext<KEYIN, VALUEIN> context)
  // throws IOException, InterruptedException {
  // result = context.createOutputRecord();
  // }
  //
  // /** Writes all keys and values directly to output. */
  // @Override
  // public void reduce(KEYIN key, Iterable<VALUEIN> values,
  // ReduceContext<KEYIN, VALUEIN> context) throws IOException,
  // InterruptedException {
  //
  // result.set(0, (WritableComparable) key);
  // for (VALUEIN v : values) {
  // result.set(1, (Writable) v);
  // context.write(result);
  // }
  // }
  // }
  