org.apache.hadoop.mapred

接口 MapRunnable<K1,V1,K2,V2>

所有超级接口:

JobConfigurable

所有已知实现类:

MapRunner, MultithreadedMapRunner, PipeMapRunner

public interface MapRunnable<K1,V1,K2,V2>
extends JobConfigurable

Expert: Generic interface for Mappers.

Custom implementations of MapRunnable can exert greater control on map processing e.g. multi-threaded, asynchronous mappers etc.

另请参阅:

Mapper

方法概要

方法

限定符和类型	方法和说明
void	run(RecordReader<K1,V1> input, OutputCollector<K2,V2> output, Reporter reporter) Start mapping input <key, value> pairs.

从接口继承的方法 org.apache.hadoop.mapred.JobConfigurable

configure

方法详细资料

run

void run(RecordReader<K1,V1> input,
       OutputCollector<K2,V2> output,
       Reporter reporter)
         throws IOException

Start mapping input <key, value> pairs.

Mapping of input records to output records is complete when this method returns.

参数:

input - the RecordReader to read the input records.

output - the OutputCollector to collect the outputrecords.

reporter - Reporter to report progress, status-updates etc.

抛出:

IOException