Examples of org.apache.hadoop.mapred.Mapper

org.apache.hadoop.mapred.Mapper

ess the <key, value> pair (assume this takes a while) // ... // ... // Let the framework know that we are alive, and kicking! // reporter.progress(); // Process some more // ... // ... // Increment the no. of <key, value> pairs processed ++noRecords; // Increment counters reporter.incrCounter(NUM_RECORDS, 1); // Every 100 records update application-level status if ((noRecords%100) == 0) { reporter.setStatus(mapTaskId + " processed " + noRecords + " from input-file: " + inputFile); } // Output the result output.collect(key, val); } }

Applications may write a custom {@link MapRunnable} to exert greatercontrol on map processing e.g. multi-threaded Mappers etc.

@see JobConf @see InputFormat @see Partitioner @see Reducer @see MapReduceBase @see MapRunnable @see SequenceFile

   * Chains the <code>map(...)</code> methods of the Mappers in the chain.
   */
  @SuppressWarnings({"unchecked"})
  public void map(Object key, Object value, OutputCollector output,
                  Reporter reporter) throws IOException {
    Mapper mapper = chain.getFirstMap();
    if (mapper != null) {
      mapper.map(key, value, chain.getMapperCollector(0, output, reporter),
                 reporter);
    }
  }

   * Chains the <code>map(...)</code> methods of the Mappers in the chain.
   */
  @SuppressWarnings({"unchecked"})
  public void map(Object key, Object value, OutputCollector output,
                  Reporter reporter) throws IOException {
    Mapper mapper = chain.getFirstMap();
    if (mapper != null) {
      mapper.map(key, value, chain.getMapperCollector(0, output, reporter),
                 reporter);
    }
  }

   * Chains the <code>map(...)</code> methods of the Mappers in the chain.
   */
  @SuppressWarnings({"unchecked"})
  public void map(Object key, Object value, OutputCollector output,
                  Reporter reporter) throws IOException {
    Mapper mapper = chain.getFirstMap();
    if (mapper != null) {
      mapper.map(key, value, chain.getMapperCollector(0, output, reporter),
                 reporter);
    }
  }

Examples of org.apache.hadoop.mapred.Mapper

Related Classes of org.apache.hadoop.mapred.Mapper