## Uses of Class
org.apache.hadoop.mapreduce.Reducer.Context

- Packages that use Reducer.Context
  Package | Description
  --- | ---
  org.apache.hadoop.mapred |
  org.apache.hadoop.mapreduce |
  org.apache.hadoop.mapreduce.lib.aggregate |
  org.apache.hadoop.mapreduce.lib.chain |
  org.apache.hadoop.mapreduce.lib.fieldsel |
  org.apache.hadoop.mapreduce.lib.reduce |

- - ### Uses of Reducer.Context in org.apache.hadoop.mapred

    Methods in org.apache.hadoop.mapred that return Reducer.Context
    Modifier and Type | Method and Description
    --- | ---
    `protected static <INKEY,INVALUE,OUTKEY,OUTVALUE> Reducer.Context` | Task.`createReduceContext(Reducer<INKEY,INVALUE,OUTKEY,OUTVALUE> reducer, org.apache.hadoop.conf.Configuration job, TaskAttemptID taskId, RawKeyValueIterator rIter, Counter inputKeyCounter, Counter inputValueCounter, RecordWriter<OUTKEY,OUTVALUE> output, OutputCommitter committer, StatusReporter reporter, org.apache.hadoop.io.RawComparator<INKEY> comparator, Class<INKEY> keyClass, Class<INVALUE> valueClass)`

  - ### Uses of Reducer.Context in org.apache.hadoop.mapreduce

    Methods in org.apache.hadoop.mapreduce with parameters of type Reducer.Context
    Modifier and Type | Method and Description
    --- | ---
    `protected void` | Reducer.`cleanup(Reducer.Context context)` Called once at the end of the task.
    `protected void` | Reducer.`reduce(KEYIN key, Iterable<VALUEIN> values, Reducer.Context context)` This method is called once for each key.
    `void` | Reducer.`run(Reducer.Context context)` Advanced application writers can use the `Reducer.run(org.apache.hadoop.mapreduce.Reducer.Context)` method to control how the reduce task works.
    `protected void` | Reducer.`setup(Reducer.Context context)` Called once at the start of the task.

  - ### Uses of Reducer.Context in org.apache.hadoop.mapreduce.lib.aggregate

    Methods in org.apache.hadoop.mapreduce.lib.aggregate with parameters of type Reducer.Context
    Modifier and Type | Method and Description
    --- | ---
    `void` | ValueAggregatorReducer.`reduce(org.apache.hadoop.io.Text key, Iterable<org.apache.hadoop.io.Text> values, Reducer.Context context)`
    `void` | ValueAggregatorCombiner.`reduce(org.apache.hadoop.io.Text key, Iterable<org.apache.hadoop.io.Text> values, Reducer.Context context)` Combines values for a given key.
    `void` | ValueAggregatorReducer.`setup(Reducer.Context context)`

  - ### Uses of Reducer.Context in org.apache.hadoop.mapreduce.lib.chain

    Methods in org.apache.hadoop.mapreduce.lib.chain with parameters of type Reducer.Context
    Modifier and Type | Method and Description
    --- | ---
    `void` | ChainReducer.`run(Reducer.Context context)`
    `protected void` | ChainReducer.`setup(Reducer.Context context)`

  - ### Uses of Reducer.Context in org.apache.hadoop.mapreduce.lib.fieldsel

    Methods in org.apache.hadoop.mapreduce.lib.fieldsel with parameters of type Reducer.Context
    Modifier and Type | Method and Description
    --- | ---
    `void` | FieldSelectionReducer.`reduce(org.apache.hadoop.io.Text key, Iterable<org.apache.hadoop.io.Text> values, Reducer.Context context)`
    `void` | FieldSelectionReducer.`setup(Reducer.Context context)`

  - ### Uses of Reducer.Context in org.apache.hadoop.mapreduce.lib.reduce

    Subclasses of Reducer.Context in org.apache.hadoop.mapreduce.lib.reduce
    Modifier and Type | Class and Description
    --- | ---
    `class` | `WrappedReducer.Context`

    Methods in org.apache.hadoop.mapreduce.lib.reduce that return Reducer.Context
    Modifier and Type | Method and Description
    --- | ---
    `Reducer.Context` | WrappedReducer.`getReducerContext(ReduceContext<KEYIN,VALUEIN,KEYOUT,VALUEOUT> reduceContext)` A a wrapped `Reducer.Context` for custom implementations.

    Methods in org.apache.hadoop.mapreduce.lib.reduce with parameters of type Reducer.Context
    Modifier and Type | Method and Description
    --- | ---
    `void` | IntSumReducer.`reduce(Key key, Iterable<org.apache.hadoop.io.IntWritable> values, Reducer.Context context)`
    `void` | LongSumReducer.`reduce(KEY key, Iterable<org.apache.hadoop.io.LongWritable> values, Reducer.Context context)`

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