org.apache.hadoop.mapreduce.lib.input

类 SequenceFileRecordReader<K,V>

java.lang.Object

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

org.apache.hadoop.mapreduce.lib.input.SequenceFileRecordReader<K,V>

所有已实现的接口:

Closeable, AutoCloseable

public class SequenceFileRecordReader<K,V>
extends RecordReader<K,V>

An RecordReader for SequenceFiles.

字段概要

字段

限定符和类型	字段和说明
protected Configuration	conf

构造器概要

构造器

构造器和说明
SequenceFileRecordReader()

方法概要

方法

限定符和类型	方法和说明
void	close() Close the record reader.
K	getCurrentKey() Get the current key
V	getCurrentValue() Get the current value.
float	getProgress() Return the progress within the input split
void	initialize(InputSplit split, TaskAttemptContext context) Called once at initialization.
boolean	nextKeyValue() Read the next key, value pair.

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

conf

protected Configuration conf

构造器详细资料

SequenceFileRecordReader

public SequenceFileRecordReader()

方法详细资料

initialize

public void initialize(InputSplit split,
              TaskAttemptContext context)
                throws IOException,
                       InterruptedException

从类复制的说明: RecordReader

Called once at initialization.

指定者:

initialize 在类中 RecordReader<K,V>

参数:

split - the split that defines the range of records to read

context - the information about the task

抛出:

IOException

InterruptedException

nextKeyValue

public boolean nextKeyValue()
                     throws IOException,
                            InterruptedException

从类复制的说明: RecordReader

Read the next key, value pair.

指定者:

nextKeyValue 在类中 RecordReader<K,V>

返回:

true if a key/value pair was read

抛出:

IOException

InterruptedException

getCurrentKey

public K getCurrentKey()

从类复制的说明: RecordReader

Get the current key

指定者:

getCurrentKey 在类中 RecordReader<K,V>

返回:

the current key or null if there is no current key

getCurrentValue

public V getCurrentValue()

从类复制的说明: RecordReader

Get the current value.

指定者:

getCurrentValue 在类中 RecordReader<K,V>

返回:

the object that was read

getProgress

public float getProgress()
                  throws IOException

Return the progress within the input split

指定者:

getProgress 在类中 RecordReader<K,V>

返回:

0.0 to 1.0 of the input byte range

抛出:

IOException

close

public void close()
           throws IOException

从类复制的说明: RecordReader

Close the record reader.

指定者:

close 在接口中 Closeable

指定者:

close 在接口中 AutoCloseable

指定者:

close 在类中 RecordReader<K,V>

抛出:

IOException