| Package | Description | 
|---|---|
| org.apache.hadoop.mapred | |
| org.apache.hadoop.mapred.lib | |
| org.apache.hadoop.mapred.lib.aggregate | 
| Modifier and Type | Method and Description | 
|---|---|
| void | Mapper. map(K1 key,
   V1 value,
   OutputCollector<K2,V2> output,
   Reporter reporter)Maps a single input key/value pair into an intermediate key/value pair. | 
| void | Reducer. reduce(K2 key,
      Iterator<V2> values,
      OutputCollector<K3,V3> output,
      Reporter reporter)Reduces values for a given key. | 
| void | MapRunner. run(RecordReader<K1,V1> input,
   OutputCollector<K2,V2> output,
   Reporter reporter) | 
| void | MapRunnable. run(RecordReader<K1,V1> input,
   OutputCollector<K2,V2> output,
   Reporter reporter)Start mapping input <key, value> pairs. | 
| Modifier and Type | Method and Description | 
|---|---|
| OutputCollector | MultipleOutputs. getCollector(String namedOutput,
            Reporter reporter)Gets the output collector for a named output. | 
| OutputCollector | MultipleOutputs. getCollector(String namedOutput,
            String multiName,
            Reporter reporter)Gets the output collector for a multi named output. | 
| Modifier and Type | Method and Description | 
|---|---|
| void | RegexMapper. map(K key,
   Text value,
   OutputCollector<Text,LongWritable> output,
   Reporter reporter) | 
| void | TokenCountMapper. map(K key,
   Text value,
   OutputCollector<Text,LongWritable> output,
   Reporter reporter) | 
| void | IdentityMapper. map(K key,
   V val,
   OutputCollector<K,V> output,
   Reporter reporter)The identify function. | 
| void | FieldSelectionMapReduce. map(K key,
   V val,
   OutputCollector<Text,Text> output,
   Reporter reporter)The identify function. | 
| void | InverseMapper. map(K key,
   V value,
   OutputCollector<V,K> output,
   Reporter reporter)The inverse function. | 
| void | ChainMapper. map(Object key,
   Object value,
   OutputCollector output,
   Reporter reporter)Chains the  map(...)methods of the Mappers in the chain. | 
| void | LongSumReducer. reduce(K key,
      Iterator<LongWritable> values,
      OutputCollector<K,LongWritable> output,
      Reporter reporter) | 
| void | IdentityReducer. reduce(K key,
      Iterator<V> values,
      OutputCollector<K,V> output,
      Reporter reporter)Writes all keys and values directly to output. | 
| void | ChainReducer. reduce(Object key,
      Iterator values,
      OutputCollector output,
      Reporter reporter)Chains the  reduce(...)method of the Reducer with themap(...) methods of the Mappers in the chain. | 
| void | FieldSelectionMapReduce. reduce(Text key,
      Iterator<Text> values,
      OutputCollector<Text,Text> output,
      Reporter reporter) | 
| void | MultithreadedMapRunner. run(RecordReader<K1,V1> input,
   OutputCollector<K2,V2> output,
   Reporter reporter) | 
| Modifier and Type | Method and Description | 
|---|---|
| void | ValueAggregatorReducer. map(K1 arg0,
   V1 arg1,
   OutputCollector<Text,Text> arg2,
   Reporter arg3)Do nothing. | 
| void | ValueAggregatorMapper. map(K1 key,
   V1 value,
   OutputCollector<Text,Text> output,
   Reporter reporter)the map function. | 
| void | ValueAggregatorCombiner. map(K1 arg0,
   V1 arg1,
   OutputCollector<Text,Text> arg2,
   Reporter arg3)Do nothing. | 
| void | ValueAggregatorReducer. reduce(Text key,
      Iterator<Text> values,
      OutputCollector<Text,Text> output,
      Reporter reporter) | 
| void | ValueAggregatorMapper. reduce(Text arg0,
      Iterator<Text> arg1,
      OutputCollector<Text,Text> arg2,
      Reporter arg3)Do nothing. | 
| void | ValueAggregatorCombiner. reduce(Text key,
      Iterator<Text> values,
      OutputCollector<Text,Text> output,
      Reporter reporter)Combines values for a given key. | 
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