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.io;
  
  import java.io.BufferedOutputStream;
  import java.io.IOException;
  
  /**
   * OutputBlobWritable表示ODPS表或分区中列类型为blob的输出接口, 该接口只能用于
   * {@link com.aliyun.odps.mapreduce.Reducer}向 {@link com.aliyun.odps.Record}
   * 中写入blob类型的列.
   * <p>
   * 用法示例：
   *
   * <pre>
   * &#064;Override
   * public void reduce(KEYIN key, Iterable&lt;VALUEIN&gt; values,
   *     MapContext&lt;KEYIN, VALUEIN&gt; context) throws IOException {
   *   Record outputRecord = context.createOutputRecord();
   *   OutputBlobWritable blob = outputRecord.get(0);
   *   BufferedOutputStream out = blob.getOutputStream();
   *   // 使用out.write向blob中写入数据
   *   out.close();
   * }
   * </pre>
   *
   * 从上面的示例看出, 从{@link com.aliyun.odps.Record}获得OutputBlobWritable接口,
   * 调用OutputBlobWritable的 getOutputStream获得BufferedOutputStream后，即可进行写入数据.
   * </p>
   */
  public interface OutputBlobWritable extends WritableComparable {
  
    /**
     * getOutputStream方法获取可以写入blob的{@link BufferedOutputStream}接口
     *
     * @return blob列对应的{@link BufferedOutputStream}
     * @throws IOException
     */
    public BufferedOutputStream getOutputStream() throws IOException;
  }
  