Package org.apache.hadoop.mapred

Interface Summary

Interface	Description
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.
InputSplitWithLocationInfo
JobConfigurable	That what may be configured.
JobContext
Mapper<K1,V1,K2,V2>	Maps input key/value pairs to a set of intermediate key/value pairs.
MapRunnable<K1,V1,K2,V2>	Expert: Generic interface for Mappers.
OutputCollector<K,V>	Collects the <key, value> pairs output by Mappers and Reducers.
OutputFormat<K,V>	OutputFormat describes the output-specification for a Map-Reduce job.
Partitioner<K2,V2>	Partitions the key space.
RecordReader<K,V>	RecordReader reads <key, value> pairs from an InputSplit.
RecordWriter<K,V>	RecordWriter writes the output <key, value> pairs to an output file.
Reducer<K2,V2,K3,V3>	Reduces a set of intermediate values which share a key to a smaller set of values.
Reporter	A facility for Map-Reduce applications to report progress and update counters, status information etc.
RunningJob	RunningJob is the user-interface to query for details on a running Map-Reduce job.
TaskAttemptContext

Class Summary

Class	Description
ClusterStatus	Status information on the current state of the Map-Reduce cluster.
Counters	A set of named counters.
Counters.Counter	A counter record, comprising its name and value.
Counters.Group	Group of counters, comprising of counters from a particular counter Enum class.
FileInputFormat<K,V>	A base class for file-based InputFormat.
FileOutputCommitter	An OutputCommitter that commits files specified in job output directory i.e.
FileOutputFormat<K,V>	A base class for OutputFormat.
FileSplit	A section of an input file.
FixedLengthInputFormat	FixedLengthInputFormat is an input format used to read input files which contain fixed length records.
ID	A general identifier, which internally stores the id as an integer.
JobClient	JobClient is the primary interface for the user-job to interact with the cluster.
JobConf	A map/reduce job configuration.
JobID	JobID represents the immutable and unique identifier for the job.
JobQueueInfo	Class that contains the information regarding the Job Queues which are maintained by the Hadoop Map/Reduce framework.
JobStatus	Describes the current status of a job.
KeyValueLineRecordReader	This class treats a line in the input as a key/value pair separated by a separator character.
KeyValueTextInputFormat	An InputFormat for plain text files.
MapFileOutputFormat	An OutputFormat that writes MapFiles.
MapReduceBase	Base class for Mapper and Reducer implementations.
MapRunner<K1,V1,K2,V2>	Default MapRunnable implementation.
MultiFileInputFormat<K,V>	An abstract InputFormat that returns MultiFileSplit's in MultiFileInputFormat.getSplits(JobConf, int) method.
MultiFileSplit	A sub-collection of input files.
OutputCommitter	OutputCommitter describes the commit of task output for a Map-Reduce job.
OutputLogFilter	This class filters log files from directory given It doesnt accept paths having _logs.
SequenceFileAsBinaryInputFormat	InputFormat reading keys, values from SequenceFiles in binary (raw) format.
SequenceFileAsBinaryOutputFormat	An OutputFormat that writes keys, values to SequenceFiles in binary(raw) format
SequenceFileAsTextInputFormat	This class is similar to SequenceFileInputFormat, except it generates SequenceFileAsTextRecordReader which converts the input keys and values to their String forms by calling toString() method.
SequenceFileAsTextRecordReader	This class converts the input keys and values to their String forms by calling toString() method.
SequenceFileInputFilter<K,V>	A class that allows a map/red job to work on a sample of sequence files.
SequenceFileInputFormat<K,V>	An InputFormat for SequenceFiles.
SequenceFileOutputFormat<K,V>	An OutputFormat that writes SequenceFiles.
SequenceFileRecordReader<K,V>	An RecordReader for SequenceFiles.
SkipBadRecords	Utility class for skip bad records functionality.
SplitLocationInfo
TaskAttemptID	TaskAttemptID represents the immutable and unique identifier for a task attempt.
TaskCompletionEvent	This is used to track task completion events on job tracker.
TaskID	TaskID represents the immutable and unique identifier for a Map or Reduce Task.
TaskReport	A report on the state of a task.
TextInputFormat	An InputFormat for plain text files.
TextOutputFormat<K,V>	An OutputFormat that writes plain text files.
Utils	A utility class.

Enum Summary

Enum	Description
JobPriority	Used to describe the priority of the running job.
TaskCompletionEvent.Status

Exception Summary

Exception	Description
FileAlreadyExistsException	Used when target file already exists for any operation and is not configured to be overwritten.
InvalidFileTypeException	Used when file type differs from the desired file type.
InvalidInputException	This class wraps a list of problems with the input, so that the user can get a list of problems together instead of finding and fixing them one by one.
InvalidJobConfException	This exception is thrown when jobconf misses some mendatory attributes or value of some attributes is invalid.