org.apache.hadoop.mapreduce.lib.input

类 KeyValueTextInputFormat

java.lang.Object

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

org.apache.hadoop.mapreduce.lib.input.FileInputFormat<Text,Text>

org.apache.hadoop.mapreduce.lib.input.KeyValueTextInputFormat

@InterfaceAudience.Public
@InterfaceStability.Stable
public class KeyValueTextInputFormat
extends FileInputFormat<Text,Text>

An InputFormat for plain text files. Files are broken into lines. Either line feed or carriage-return are used to signal end of line. Each line is divided into key and value parts by a separator byte. If no such a byte exists, the key will be the entire line and value will be empty.

嵌套类概要

从类继承的嵌套类/接口 org.apache.hadoop.mapreduce.lib.input.FileInputFormat

FileInputFormat.Counter

构造器概要

构造器

构造器和说明
KeyValueTextInputFormat()

方法概要

方法

限定符和类型	方法和说明
RecordReader<Text,Text>	createRecordReader(InputSplit genericSplit, TaskAttemptContext context) Create a record reader for a given split.
protected boolean	isSplitable(JobContext context, Path file) Is the given filename splitable?

从类继承的方法 org.apache.hadoop.mapreduce.lib.input.FileInputFormat

addInputPath, addInputPaths, computeSplitSize, getBlockIndex, getFormatMinSplitSize, getInputPathFilter, getInputPaths, getMaxSplitSize, getMinSplitSize, getSplits, listStatus, setInputPathFilter, setInputPaths, setInputPaths, setMaxInputSplitSize, setMinInputSplitSize

从类继承的方法 java.lang.Object

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

构造器详细资料

KeyValueTextInputFormat

public KeyValueTextInputFormat()

方法详细资料

isSplitable

protected boolean isSplitable(JobContext context,
                  Path file)

从类复制的说明: FileInputFormat

Is the given filename splitable? Usually, true, but if the file is stream compressed, it will not be. FileInputFormat implementations can override this and return false to ensure that individual input files are never split-up so that Mappers process entire files.

覆盖:

isSplitable 在类中 FileInputFormat<Text,Text>

参数:

context - the job context

file - the file name to check

返回:

is this file splitable?

createRecordReader

public RecordReader<Text,Text> createRecordReader(InputSplit genericSplit,
                                         TaskAttemptContext context)
                                           throws IOException

从类复制的说明: InputFormat

Create a record reader for a given split. The framework will call RecordReader.initialize(InputSplit, TaskAttemptContext) before the split is used.

指定者:

createRecordReader 在类中 InputFormat<Text,Text>

参数:

genericSplit - the split to be read

context - the information about the task

返回:

a new record reader

抛出:

IOException