org.apache.hadoop.mapreduce.lib.output

类 LazyOutputFormat<K,V>

java.lang.Object

org.apache.hadoop.mapreduce.OutputFormat<K,V>

org.apache.hadoop.mapreduce.lib.output.FilterOutputFormat<K,V>

org.apache.hadoop.mapreduce.lib.output.LazyOutputFormat<K,V>

@InterfaceAudience.Public
@InterfaceStability.Stable
public class LazyOutputFormat<K,V>
extends FilterOutputFormat<K,V>

A Convenience class that creates output lazily.

嵌套类概要

从类继承的嵌套类/接口 org.apache.hadoop.mapreduce.lib.output.FilterOutputFormat

FilterOutputFormat.FilterRecordWriter<K,V>

字段概要

字段

限定符和类型	字段和说明
static String	OUTPUT_FORMAT

从类继承的字段 org.apache.hadoop.mapreduce.lib.output.FilterOutputFormat

baseOut

构造器概要

构造器

构造器和说明
LazyOutputFormat()

方法概要

方法

限定符和类型	方法和说明
void	checkOutputSpecs(JobContext context) Check for validity of the output-specification for the job.
OutputCommitter	getOutputCommitter(TaskAttemptContext context) Get the output committer for this output format.
RecordWriter<K,V>	getRecordWriter(TaskAttemptContext context) Get the RecordWriter for the given task.
static void	setOutputFormatClass(Job job, Class<? extends OutputFormat> theClass) Set the underlying output format for LazyOutputFormat.

从类继承的方法 java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

字段详细资料

OUTPUT_FORMAT

public static String OUTPUT_FORMAT

构造器详细资料

LazyOutputFormat

public LazyOutputFormat()

方法详细资料

setOutputFormatClass

public static void setOutputFormatClass(Job job,
                        Class<? extends OutputFormat> theClass)

Set the underlying output format for LazyOutputFormat.

参数:

job - the Job to modify

theClass - the underlying class

getRecordWriter

public RecordWriter<K,V> getRecordWriter(TaskAttemptContext context)
                                  throws IOException,
                                         InterruptedException

从类复制的说明: OutputFormat

Get the RecordWriter for the given task.

覆盖:

getRecordWriter 在类中 FilterOutputFormat<K,V>

参数:

context - the information about the current task.

返回:

a RecordWriter to write the output for the job.

抛出:

IOException

InterruptedException

checkOutputSpecs

public void checkOutputSpecs(JobContext context)
                      throws IOException,
                             InterruptedException

从类复制的说明: OutputFormat

Check for validity of the output-specification for the job.

This is to validate the output specification for the job when it is a job is submitted. Typically checks that it does not already exist, throwing an exception when it already exists, so that output is not overwritten.

覆盖:

checkOutputSpecs 在类中 FilterOutputFormat<K,V>

参数:

context - information about the job

抛出:

IOException - when output should not be attempted

InterruptedException

getOutputCommitter

public OutputCommitter getOutputCommitter(TaskAttemptContext context)
                                   throws IOException,
                                          InterruptedException

从类复制的说明: OutputFormat

Get the output committer for this output format. This is responsible for ensuring the output is committed correctly.

覆盖:

getOutputCommitter 在类中 FilterOutputFormat<K,V>

参数:

context - the task context

返回:

an output committer

抛出:

IOException

InterruptedException