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 org.apache.hadoop.chukwa.datacollection.writer;
  
  import java.util.List;
  import org.apache.hadoop.chukwa.Chunk;
  import org.apache.hadoop.conf.Configuration;
  import org.apache.log4j.Logger;
  import org.apache.hadoop.chukwa.util.ExceptionUtil;
  
  /**
   * Minimal writer; does nothing with data.
   * 
   * Useful primarily as an end-of-pipeline stage, if stuff in the middle
   * is accomplishing something useful.
   *
   */
  public class NullWriter implements ChukwaWriter {
    private static final Logger log = Logger.getLogger(NullWriter.class);
    
    //in kb per sec
    int maxDataRate = Integer.MAX_VALUE;
    public static final String RATE_OPT_NAME = "nullWriter.dataRate";
    @Override
    public CommitStatus add(List<Chunk> chunks) throws WriterException {
      try {
        int dataBytes =0;
        for(Chunk c: chunks)
          dataBytes +=c.getData().length;
        if(maxDataRate > 0)
          Thread.sleep(dataBytes / maxDataRate);
      } catch(Exception e) {
        log.debug(ExceptionUtil.getStackTrace(e));
      }
      return COMMIT_OK;
    }
  
    @Override
    public void close() throws WriterException {
    }
  
    @Override
    public void init(Configuration c) throws WriterException {
      maxDataRate = c.getInt(RATE_OPT_NAME, 0);
    }
  
  }
  