org.apache.hadoop.mapred.lib

クラス RegexMapper<K>

java.lang.Object

org.apache.hadoop.mapred.MapReduceBase

org.apache.hadoop.mapred.lib.RegexMapper<K>

すべての実装されたインタフェース:

Closeable, AutoCloseable, JobConfigurable, Mapper<K,Text,Text,LongWritable>

@InterfaceAudience.Public
 @InterfaceStability.Stable
public class RegexMapper<K>
extends MapReduceBase
implements Mapper<K,Text,Text,LongWritable>

A Mapper that extracts text matching a regular expression.

コンストラクタのサマリー

コンストラクタ

コンストラクタと説明
RegexMapper()

メソッドのサマリー

修飾子とタイプ	メソッドと説明
void	configure(JobConf job) Default implementation that does nothing.
void	map(K key, Text value, OutputCollector<Text,LongWritable> output, Reporter reporter) Maps a single input key/value pair into an intermediate key/value pair.

クラスから継承されたメソッド org.apache.hadoop.mapred.MapReduceBase

close

クラスから継承されたメソッド java.lang.Object

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

インタフェースから継承されたメソッド java.io.Closeable

close

コンストラクタの詳細

RegexMapper

public RegexMapper()

メソッドの詳細

configure

public void configure(JobConf job)

クラスからコピーされた説明: MapReduceBase

Default implementation that does nothing.

定義:

configure インタフェース内 JobConfigurable

オーバーライド:

configure クラス内 MapReduceBase

パラメータ:

job - the configuration

map

public void map(K key,
                Text value,
                OutputCollector<Text,LongWritable> output,
                Reporter reporter)
         throws IOException

インタフェースからコピーされた説明: Mapper

Maps a single input key/value pair into an intermediate key/value pair.

Output pairs need not be of the same types as input pairs. A given input pair may map to zero or many output pairs. Output pairs are collected with calls to OutputCollector.collect(Object,Object).

Applications can use the Reporter provided to report progress or just indicate that they are alive. In scenarios where the application takes significant amount of time to process individual key/value pairs, this is crucial since the framework might assume that the task has timed-out and kill that task. The other way of avoiding this is to set mapreduce.task.timeout to a high-enough value (or even zero for no time-outs).

定義:

map インタフェース内 Mapper<K,Text,Text,LongWritable>

パラメータ:

key - the input key.

value - the input value.

output - collects mapped keys and values.

reporter - facility to report progress.

例外:

IOException