Package org.apache.hadoop.mapreduce

Class Summary
ClusterMetrics Status information on the current state of the Map-Reduce cluster.
Counter A named counter that tracks the progress of a map/reduce job.
CounterGroup A group of Counters that logically belong together.
ID A general identifier, which internally stores the id as an integer.
InputFormat<K,V> InputFormat describes the input-specification for a Map-Reduce job.
InputSplit InputSplit represents the data to be processed by an individual Mapper.
Job The job submitter's view of the Job.
JobContext A read-only view of the job that is provided to the tasks while they are running.
JobID JobID represents the immutable and unique identifier for the job.
JobStatus Describes the current status of a job.
JobSubmissionFiles A utility to manage job submission files.
Note that this class is for framework internal usage only and is not to be used by users directly.
MapContext<KEYIN,VALUEIN,KEYOUT,VALUEOUT> The context that is given to the Mapper.
Mapper<KEYIN,VALUEIN,KEYOUT,VALUEOUT> Maps input key/value pairs to a set of intermediate key/value pairs.
OutputCommitter OutputCommitter describes the commit of task output for a Map-Reduce job.
OutputFormat<K,V> OutputFormat describes the output-specification for a Map-Reduce job.
Partitioner<KEY,VALUE> Partitions the key space.
RecordReader<KEYIN,VALUEIN> The record reader breaks the data into key/value pairs for input to the Mapper.
RecordWriter<K,V> RecordWriter writes the output <key, value> pairs to an output file.
ReduceContext<KEYIN,VALUEIN,KEYOUT,VALUEOUT> The context passed to the Reducer.
Reducer<KEYIN,VALUEIN,KEYOUT,VALUEOUT> Reduces a set of intermediate values which share a key to a smaller set of values.
TaskAttemptContext The context for task attempts.
TaskAttemptID TaskAttemptID represents the immutable and unique identifier for a task attempt.
TaskID TaskID represents the immutable and unique identifier for a Map or Reduce Task.
TaskInputOutputContext<KEYIN,VALUEIN,KEYOUT,VALUEOUT> A context object that allows input and output from the task.

Enum Summary
JobACL Job related ACLs
JobStatus.State Current state of the job
TaskType Enum for map, reduce, job-setup, job-cleanup, task-cleanup task types.

Copyright © 2009 The Apache Software Foundation