p2pMapReduce.mapreduceModule
Interface TaskInputOutputContext<KEYIN,VALUEIN,KEYOUT,VALUEOUT>

Type Parameters:
KEYIN - the input key type for the task
VALUEIN - the input value type for the task
KEYOUT - the output key type for the task
VALUEOUT - the output value type for the task
All Superinterfaces:
JobContext, MRJobConfig, TaskAttemptContext
All Known Subinterfaces:
MapContext<KEYIN,VALUEIN,KEYOUT,VALUEOUT>, ReduceContext<KEYIN,VALUEIN,KEYOUT,VALUEOUT>
All Known Implementing Classes:
MapContextImpl, Mapper.Context, ReduceContextImpl, Reducer.Context, TaskInputOutputContextImpl, WrappedMapper.Context, WrappedReducer.Context

public interface TaskInputOutputContext<KEYIN,VALUEIN,KEYOUT,VALUEOUT>
extends TaskAttemptContext

A context object that allows input and output from the task. It is only supplied to the Mapper or Reducer.


Field Summary
 
Fields inherited from interface p2pMapReduce.mapreduceModule.MRJobConfig
CACHE_ARCHIVES, CACHE_ARCHIVES_SIZES, CACHE_ARCHIVES_TIMESTAMPS, CACHE_ARCHIVES_VISIBILITIES, CACHE_FILE_TIMESTAMPS, CACHE_FILE_VISIBILITIES, CACHE_FILES, CACHE_FILES_SIZES, CACHE_LOCALARCHIVES, CACHE_LOCALFILES, CACHE_SYMLINK, CLASSPATH_ARCHIVES, CLASSPATH_FILES, COMBINE_CLASS_ATTR, COMPLETED_MAPS_FOR_REDUCE_SLOWSTART, END_NOTIFICATION_RETRIE_INTERVAL, END_NOTIFICATION_RETRIES, END_NOTIFICATION_URL, GROUP_COMPARATOR_CLASS, HISTORY_LOCATION, ID, INPUT_FORMAT_CLASS_ATTR, INPUTSPLIT_CLASS_ATTR, INPUTSPLIT_SIZE, IO_SORT_FACTOR, IO_SORT_MB, JAR, JAR_UNPACK_PATTERN, JOB_ACL_MODIFY_JOB, JOB_ACL_VIEW_JOB, JOB_CANCEL_DELEGATION_TOKEN, JOB_DIR_ATTR, JOB_INPUT_DIR_ATTR, JOB_INPUTSPLIT_DIR_ATTR, JOB_JAR_DIR_ATTR, JOB_JOBTRACKER_ID, JOB_LOCAL_DIR, JOB_NAME, JOB_NAMENODES, JOB_OUTPUT_DIR_ATTR, JVM_NUMTASKS_TORUN, KEY_COMPARATOR, MAP_CLASS_ATTR, MAP_COMBINE_MIN_SPILLS, MAP_DEBUG_SCRIPT, MAP_ENV, MAP_FAILURES_MAX_PERCENT, MAP_INPUT_FILE, MAP_INPUT_PATH, MAP_INPUT_START, MAP_JAVA_OPTS, MAP_LOG_LEVEL, MAP_MAX_ATTEMPTS, MAP_MEMORY_MB, MAP_MEMORY_PHYSICAL_MB, MAP_OUTPUT_COMPRESS, MAP_OUTPUT_COMPRESS_CODEC, MAP_OUTPUT_DIR_ATTR, MAP_OUTPUT_KEY_CLASS, MAP_OUTPUT_KEY_FIELD_SEPERATOR, MAP_OUTPUT_KEY_VALUE_SEPARATOR_ATTR, MAP_OUTPUT_VALUE_CLASS, MAP_SKIP_INCR_PROC_COUNT, MAP_SKIP_MAX_RECORDS, MAP_SORT_SPILL_PERCENT, MAP_SPECULATIVE, MAP_ULIMIT, MAX_TASK_FAILURES_PER_TRACKER, NUM_MAP_PROFILES, NUM_MAPS, NUM_REDUCE_PROFILES, NUM_REDUCES, OUTPUT_FORMAT_CLASS_ATTR, OUTPUT_KEY_CLASS, OUTPUT_VALUE_CLASS, PARTITIONER_CLASS_ATTR, PRESERVE_FAILED_TASK_FILES, PRESERVE_FILES_PATTERN, PRIORITY, QUEUE_NAME, RECORDS_BEFORE_PROGRESS, REDUCE_CLASS_ATTR, REDUCE_DEBUG_SCRIPT, REDUCE_ENV, REDUCE_FAILURES_MAXPERCENT, REDUCE_INPUT_BUFFER_PERCENT, REDUCE_INPUT_DIR_ATTR, REDUCE_JAVA_OPTS, REDUCE_LOG_LEVEL, REDUCE_MARKRESET_BUFFER_PERCENT, REDUCE_MARKRESET_BUFFER_SIZE, REDUCE_MAX_ATTEMPTS, REDUCE_MEMORY_MB, REDUCE_MEMORY_PHYSICAL_MB, REDUCE_MEMORY_TOTAL_BYTES, REDUCE_MEMTOMEM_ENABLED, REDUCE_MEMTOMEM_THRESHOLD, REDUCE_MERGE_INMEM_THRESHOLD, REDUCE_OUTPUT_DIR_ATTR, REDUCE_SKIP_INCR_PROC_COUNT, REDUCE_SKIP_MAXGROUPS, REDUCE_SPECULATIVE, REDUCE_ULIMIT, SETUP_CLEANUP_NEEDED, SHUFFLE_CONNECT_TIMEOUT, SHUFFLE_FETCH_FAILURES, SHUFFLE_INPUT_BUFFER_PERCENT, SHUFFLE_MERGE_EPRCENT, SHUFFLE_NOTIFY_READERROR, SHUFFLE_PARALLEL_COPIES, SHUFFLE_READ_TIMEOUT, SKIP_OUTDIR, SKIP_RECORDS, SKIP_START_ATTEMPTS, SPECULATIVE_SLOWNODE_THRESHOLD, SPECULATIVE_SLOWTASK_THRESHOLD, SPECULATIVECAP, SPLIT_FILE, TASK_ATTEMPT_ID, TASK_DEBUGOUT_LINES, TASK_ID, TASK_ISMAP, TASK_OUTPUT_DIR, TASK_PARTITION, TASK_PROFILE, TASK_PROFILE_PARAMS, TASK_TEMP_DIR, TASK_TIMEOUT, TASK_USERLOG_LIMIT, USER_LOG_RETAIN_HOURS, USER_NAME, WORKING_DIR
 
Method Summary
 Counter getCounter(java.lang.Enum<?> counterName)
          Get the Counter for the given counterName.
 Counter getCounter(java.lang.String groupName, java.lang.String counterName)
          Get the Counter for the given groupName and counterName.
 KEYIN getCurrentKey()
          Get the current key.
 VALUEIN getCurrentValue()
          Get the current value.
 OutputCommitter getOutputCommitter()
          Get the OutputCommitter for the task-attempt.
 boolean nextKeyValue()
          Advance to the next key, value pair, returning null if at end.
 void write(KEYOUT key, VALUEOUT value)
          Generate an output key/value pair.
 
Methods inherited from interface p2pMapReduce.mapreduceModule.TaskAttemptContext
getStatus, getTaskAttemptID, setStatus
 
Methods inherited from interface p2pMapReduce.mapreduceModule.JobContext
getCombinerClass, getConfiguration, getInputFormatClass, getJar, getJobID, getJobName, getJobSetupCleanupNeeded, getMapOutputKeyClass, getMapOutputValueClass, getMapperClass, getMaxMapAttempts, getMaxReduceAttempts, getNumReduceTasks, getOutputFormatClass, getOutputKeyClass, getOutputValueClass, getPartitionerClass, getProfileEnabled, getProfileParams, getProfileTaskRange, getReducerClass, getSortComparator, getUser, getWorkingDirectory
 

Method Detail

nextKeyValue

boolean nextKeyValue()
                     throws java.io.IOException,
                            java.lang.InterruptedException
Advance to the next key, value pair, returning null if at end.

Returns:
the key object that was read into, or null if no more
Throws:
java.io.IOException
java.lang.InterruptedException

getCurrentKey

KEYIN getCurrentKey()
                    throws java.io.IOException,
                           java.lang.InterruptedException
Get the current key.

Returns:
the current key object or null if there isn't one
Throws:
java.io.IOException
java.lang.InterruptedException

getCurrentValue

VALUEIN getCurrentValue()
                        throws java.io.IOException,
                               java.lang.InterruptedException
Get the current value.

Returns:
the value object that was read into
Throws:
java.io.IOException
java.lang.InterruptedException

write

void write(KEYOUT key,
           VALUEOUT value)
           throws java.io.IOException,
                  java.lang.InterruptedException
Generate an output key/value pair.

Throws:
java.io.IOException
java.lang.InterruptedException

getCounter

Counter getCounter(java.lang.Enum<?> counterName)
Get the Counter for the given counterName.

Parameters:
counterName - counter name
Returns:
the Counter for the given counterName

getCounter

Counter getCounter(java.lang.String groupName,
                   java.lang.String counterName)
Get the Counter for the given groupName and counterName.

Parameters:
counterName - counter name
Returns:
the Counter for the given groupName and counterName

getOutputCommitter

OutputCommitter getOutputCommitter()
Get the OutputCommitter for the task-attempt.

Returns:
the OutputCommitter for the task-attempt