## Uses of Interface
org.apache.hadoop.mapred.OutputCollector

- Packages that use OutputCollector
  Package | Description
  --- | ---
  org.apache.hadoop.mapred |
  org.apache.hadoop.mapred.lib |
  org.apache.hadoop.mapred.lib.aggregate |

- - ### Uses of OutputCollector in org.apache.hadoop.mapred

    Methods in org.apache.hadoop.mapred with parameters of type OutputCollector
    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.

  - ### Uses of OutputCollector in org.apache.hadoop.mapred.lib

    Methods in org.apache.hadoop.mapred.lib that return OutputCollector
    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.

    Methods in org.apache.hadoop.mapred.lib with parameters of type OutputCollector
    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 identity 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 the `map(...)` 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)`

  - ### Uses of OutputCollector in org.apache.hadoop.mapred.lib.aggregate

    Methods in org.apache.hadoop.mapred.lib.aggregate with parameters of type OutputCollector
    Modifier and Type | Method and Description
    --- | ---
    `void` | ValueAggregatorMapper.`map(K1 key, V1 value, OutputCollector<Text,Text> output, Reporter reporter)` the map function.
    `void` | ValueAggregatorReducer.`map(K1 arg0, V1 arg1, OutputCollector<Text,Text> arg2, Reporter arg3)` Do nothing.
    `void` | ValueAggregatorCombiner.`map(K1 arg0, V1 arg1, OutputCollector<Text,Text> arg2, Reporter arg3)` Do nothing.
    `void` | ValueAggregatorMapper.`reduce(Text arg0, Iterator<Text> arg1, OutputCollector<Text,Text> arg2, Reporter arg3)` Do nothing.
    `void` | ValueAggregatorReducer.`reduce(Text key, Iterator<Text> values, OutputCollector<Text,Text> output, Reporter reporter)`
    `void` | ValueAggregatorCombiner.`reduce(Text key, Iterator<Text> values, OutputCollector<Text,Text> output, Reporter reporter)` Combines values for a given key.

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