org.apache.hadoop.mapreduce

Interface JobContext

All Known Subinterfaces:

JobContext, MapContext<KEYIN,VALUEIN,KEYOUT,VALUEOUT>, ReduceContext<KEYIN,VALUEIN,KEYOUT,VALUEOUT>, TaskAttemptContext, TaskAttemptContext, TaskInputOutputContext<KEYIN,VALUEIN,KEYOUT,VALUEOUT>

All Known Implementing Classes:

Job, JobContextImpl, JobContextImpl, MapContextImpl, Mapper.Context, ReduceContextImpl, Reducer.Context, TaskAttemptContextImpl, TaskAttemptContextImpl, TaskInputOutputContextImpl, WrappedMapper.Context, WrappedReducer.Context

public interface JobContext

A read-only view of the job that is provided to the tasks while they are running.

Field Summary

Fields

Modifier and Type	Field and Description
static String	CACHE_ARCHIVES_VISIBILITIES
static String	CACHE_FILE_VISIBILITIES
static String	COMBINE_CLASS_ATTR
static String	INPUT_FORMAT_CLASS_ATTR
static String	JAR_UNPACK_PATTERN
static String	JOB_ACL_MODIFY_JOB
static String	JOB_ACL_VIEW_JOB
static String	JOB_CANCEL_DELEGATION_TOKEN
static String	JOB_NAMENODES
static String	MAP_CLASS_ATTR
static String	MAP_MEMORY_PHYSICAL_MB
static String	MAP_OUTPUT_COLLECTOR_CLASS_ATTR
static String	MAPREDUCE_TASK_CLASSPATH_PRECEDENCE
static String	OUTPUT_FORMAT_CLASS_ATTR
static String	PARTITIONER_CLASS_ATTR
static String	REDUCE_CLASS_ATTR
static String	REDUCE_MEMORY_PHYSICAL_MB
static String	SHUFFLE_CONSUMER_PLUGIN_ATTR
static String	USER_LOG_RETAIN_HOURS

Method Summary

Methods

Modifier and Type	Method and Description
org.apache.hadoop.fs.Path[]	getArchiveClassPaths() Get the archive entries in classpath as an array of Path
String[]	getArchiveTimestamps() Get the timestamps of the archives.
URI[]	getCacheArchives() Get cache archives set in the Configuration
URI[]	getCacheFiles() Get cache files set in the Configuration
Class<? extends Reducer<?,?,?,?>>	getCombinerClass() Get the combiner class for the job.
org.apache.hadoop.io.RawComparator<?>	getCombinerKeyGroupingComparator() Get the user defined RawComparator comparator for grouping keys of inputs to the combiner.
org.apache.hadoop.conf.Configuration	getConfiguration() Return the configuration for the job.
org.apache.hadoop.security.Credentials	getCredentials() Get credentials for the job.
org.apache.hadoop.fs.Path[]	getFileClassPaths() Get the file entries in classpath as an array of Path
String[]	getFileTimestamps() Get the timestamps of the files.
org.apache.hadoop.io.RawComparator<?>	getGroupingComparator() Get the user defined RawComparator comparator for grouping keys of inputs to the reduce.
Class<? extends InputFormat<?,?>>	getInputFormatClass() Get the InputFormat class for the job.
String	getJar() Get the pathname of the job's jar.
JobID	getJobID() Get the unique ID for the job.
String	getJobName() Get the user-specified job name.
boolean	getJobSetupCleanupNeeded() Get whether job-setup and job-cleanup is needed for the job
org.apache.hadoop.fs.Path[]	getLocalCacheArchives() Return the path array of the localized caches
org.apache.hadoop.fs.Path[]	getLocalCacheFiles() Return the path array of the localized files
Class<?>	getMapOutputKeyClass() Get the key class for the map output data.
Class<?>	getMapOutputValueClass() Get the value class for the map output data.
Class<? extends Mapper<?,?,?,?>>	getMapperClass() Get the Mapper class for the job.
int	getMaxMapAttempts() Get the configured number of maximum attempts that will be made to run a
int	getMaxReduceAttempts() Get the configured number of maximum attempts that will be made to run a
int	getNumReduceTasks() Get configured the number of reduce tasks for this job.
Class<? extends OutputFormat<?,?>>	getOutputFormatClass() Get the OutputFormat class for the job.
Class<?>	getOutputKeyClass() Get the key class for the job output data.
Class<?>	getOutputValueClass() Get the value class for job outputs.
Class<? extends Partitioner<?,?>>	getPartitionerClass() Get the Partitioner class for the job.
boolean	getProfileEnabled() Get whether the task profiling is enabled.
String	getProfileParams()
Class<? extends Reducer<?,?,?,?>>	getReducerClass() Get the Reducer class for the job.
org.apache.hadoop.io.RawComparator<?>	getSortComparator() Get the RawComparator comparator used to compare keys.
boolean	getSymlink() This method checks to see if symlinks are to be create for the localized cache files in the current working directory
String	getUser() Get the reported username for this job.
org.apache.hadoop.fs.Path	getWorkingDirectory() Get the current working directory for the default file system.
boolean	userClassesTakesPrecedence() Get the boolean value for the property that specifies which classpath takes precedence when tasks are launched.

Field Detail

INPUT_FORMAT_CLASS_ATTR

static final String INPUT_FORMAT_CLASS_ATTR

See Also:

Constant Field Values

MAP_CLASS_ATTR

static final String MAP_CLASS_ATTR

See Also:

Constant Field Values

MAP_OUTPUT_COLLECTOR_CLASS_ATTR

static final String MAP_OUTPUT_COLLECTOR_CLASS_ATTR

See Also:

Constant Field Values

COMBINE_CLASS_ATTR

static final String COMBINE_CLASS_ATTR

See Also:

Constant Field Values

SHUFFLE_CONSUMER_PLUGIN_ATTR

static final String SHUFFLE_CONSUMER_PLUGIN_ATTR

See Also:

Constant Field Values

REDUCE_CLASS_ATTR

static final String REDUCE_CLASS_ATTR

See Also:

Constant Field Values

OUTPUT_FORMAT_CLASS_ATTR

static final String OUTPUT_FORMAT_CLASS_ATTR

See Also:

Constant Field Values

PARTITIONER_CLASS_ATTR

static final String PARTITIONER_CLASS_ATTR

See Also:

Constant Field Values

JAR_UNPACK_PATTERN

static final String JAR_UNPACK_PATTERN

See Also:

Constant Field Values

JOB_NAMENODES

static final String JOB_NAMENODES

See Also:

Constant Field Values

JOB_ACL_VIEW_JOB

static final String JOB_ACL_VIEW_JOB

See Also:

Constant Field Values

JOB_ACL_MODIFY_JOB

static final String JOB_ACL_MODIFY_JOB

See Also:

Constant Field Values

CACHE_FILE_VISIBILITIES

static final String CACHE_FILE_VISIBILITIES

See Also:

Constant Field Values

CACHE_ARCHIVES_VISIBILITIES

static final String CACHE_ARCHIVES_VISIBILITIES

See Also:

Constant Field Values

JOB_CANCEL_DELEGATION_TOKEN

static final String JOB_CANCEL_DELEGATION_TOKEN

See Also:

Constant Field Values

USER_LOG_RETAIN_HOURS

static final String USER_LOG_RETAIN_HOURS

See Also:

Constant Field Values

MAPREDUCE_TASK_CLASSPATH_PRECEDENCE

static final String MAPREDUCE_TASK_CLASSPATH_PRECEDENCE

See Also:

Constant Field Values

MAP_MEMORY_PHYSICAL_MB

static final String MAP_MEMORY_PHYSICAL_MB

See Also:

Constant Field Values

REDUCE_MEMORY_PHYSICAL_MB

static final String REDUCE_MEMORY_PHYSICAL_MB

See Also:

Constant Field Values

Method Detail

getConfiguration

org.apache.hadoop.conf.Configuration getConfiguration()

Return the configuration for the job.

Returns:

the shared configuration object

getCredentials

org.apache.hadoop.security.Credentials getCredentials()

Get credentials for the job.

Returns:

credentials for the job

getJobID

JobID getJobID()

Get the unique ID for the job.

Returns:

the object with the job id

getNumReduceTasks

int getNumReduceTasks()

Get configured the number of reduce tasks for this job. Defaults to 1.

Returns:

the number of reduce tasks for this job.

getWorkingDirectory

org.apache.hadoop.fs.Path getWorkingDirectory()
                                              throws IOException

Get the current working directory for the default file system.

Returns:

the directory name.

Throws:

IOException

getOutputKeyClass

Class<?> getOutputKeyClass()

Get the key class for the job output data.

Returns:

the key class for the job output data.

getOutputValueClass

Class<?> getOutputValueClass()

Get the value class for job outputs.

Returns:

the value class for job outputs.

getMapOutputKeyClass

Class<?> getMapOutputKeyClass()

Get the key class for the map output data. If it is not set, use the (final) output key class. This allows the map output key class to be different than the final output key class.

Returns:

the map output key class.

getMapOutputValueClass

Class<?> getMapOutputValueClass()

Get the value class for the map output data. If it is not set, use the (final) output value class This allows the map output value class to be different than the final output value class.

Returns:

the map output value class.

getJobName

String getJobName()

Get the user-specified job name. This is only used to identify the job to the user.

Returns:

the job's name, defaulting to "".

userClassesTakesPrecedence

boolean userClassesTakesPrecedence()

Get the boolean value for the property that specifies which classpath takes precedence when tasks are launched. True - user's classes takes precedence. False - system's classes takes precedence.

Returns:

true if user's classes should take precedence

getInputFormatClass

Class<? extends InputFormat<?,?>> getInputFormatClass()
                                                      throws ClassNotFoundException

Get the InputFormat class for the job.

Returns:

the InputFormat class for the job.

Throws:

ClassNotFoundException

getMapperClass

Class<? extends Mapper<?,?,?,?>> getMapperClass()
                                                throws ClassNotFoundException

Get the Mapper class for the job.

Returns:

the Mapper class for the job.

Throws:

ClassNotFoundException

getCombinerClass

Class<? extends Reducer<?,?,?,?>> getCombinerClass()
                                                   throws ClassNotFoundException

Get the combiner class for the job.

Returns:

the combiner class for the job.

Throws:

ClassNotFoundException

getReducerClass

Class<? extends Reducer<?,?,?,?>> getReducerClass()
                                                  throws ClassNotFoundException

Get the Reducer class for the job.

Returns:

the Reducer class for the job.

Throws:

ClassNotFoundException

getOutputFormatClass

Class<? extends OutputFormat<?,?>> getOutputFormatClass()
                                                        throws ClassNotFoundException

Get the OutputFormat class for the job.

Returns:

the OutputFormat class for the job.

Throws:

ClassNotFoundException

getPartitionerClass

Class<? extends Partitioner<?,?>> getPartitionerClass()
                                                      throws ClassNotFoundException

Get the Partitioner class for the job.

Returns:

the Partitioner class for the job.

Throws:

ClassNotFoundException

getSortComparator

org.apache.hadoop.io.RawComparator<?> getSortComparator()

Get the RawComparator comparator used to compare keys.

Returns:

the RawComparator comparator used to compare keys.

getJar

String getJar()

Get the pathname of the job's jar.

Returns:

the pathname

getCombinerKeyGroupingComparator

org.apache.hadoop.io.RawComparator<?> getCombinerKeyGroupingComparator()

Get the user defined RawComparator comparator for grouping keys of inputs to the combiner.

Returns:

comparator set by the user for grouping values.

See Also:

Job.setCombinerKeyGroupingComparatorClass(Class)

getGroupingComparator

org.apache.hadoop.io.RawComparator<?> getGroupingComparator()

Get the user defined RawComparator comparator for grouping keys of inputs to the reduce.

Returns:

comparator set by the user for grouping values.

See Also:

for details., getCombinerKeyGroupingComparator()

getJobSetupCleanupNeeded

boolean getJobSetupCleanupNeeded()

Get whether job-setup and job-cleanup is needed for the job

Returns:

boolean

getProfileEnabled

boolean getProfileEnabled()

Get whether the task profiling is enabled.

Returns:

true if some tasks will be profiled

getProfileParams

String getProfileParams()

Returns:

the parameters to pass to the task child to configure profiling

getUser

String getUser()

Get the reported username for this job.

Returns:

the username

getSymlink

boolean getSymlink()

This method checks to see if symlinks are to be create for the localized cache files in the current working directory

Returns:

true if symlinks are to be created- else return false

getArchiveClassPaths

org.apache.hadoop.fs.Path[] getArchiveClassPaths()

Get the archive entries in classpath as an array of Path

getCacheArchives

URI[] getCacheArchives()
                       throws IOException

Get cache archives set in the Configuration

Returns:

A URI array of the caches set in the Configuration

Throws:

IOException

getCacheFiles

URI[] getCacheFiles()
                    throws IOException

Get cache files set in the Configuration

Throws:

IOException

getLocalCacheArchives

org.apache.hadoop.fs.Path[] getLocalCacheArchives()
                                                  throws IOException

Return the path array of the localized caches

Returns:

A path array of localized caches

Throws:

IOException

getLocalCacheFiles

org.apache.hadoop.fs.Path[] getLocalCacheFiles()
                                               throws IOException

Return the path array of the localized files

Returns:

A path array of localized files

Throws:

IOException

getFileClassPaths

org.apache.hadoop.fs.Path[] getFileClassPaths()

Get the file entries in classpath as an array of Path

getArchiveTimestamps

String[] getArchiveTimestamps()

Get the timestamps of the archives. Used by internal

Returns:

a string array of timestamps

Throws:

IOException

getFileTimestamps

String[] getFileTimestamps()

Get the timestamps of the files. Used by internal

Returns:

a string array of timestamps

Throws:

IOException

getMaxMapAttempts

int getMaxMapAttempts()

Get the configured number of maximum attempts that will be made to run a

Returns:

the max number of attempts per map task.

getMaxReduceAttempts

int getMaxReduceAttempts()

Get the configured number of maximum attempts that will be made to run a

Returns:

the max number of attempts per reduce task.