org.apache.hadoop.streaming.io
Class OutputReader<K,V>

java.lang.Object
  org.apache.hadoop.streaming.io.OutputReader<K,V>

Direct Known Subclasses:

RawBytesOutputReader, TextOutputReader, TypedBytesOutputReader

public abstract class OutputReader<K,V>
extends Object

Abstract base for classes that read the client's output.

Constructor Summary

OutputReader()

Method Summary

abstract K	getCurrentKey() Returns the current key.
abstract V	getCurrentValue() Returns the current value.
abstract String	getLastOutput() Returns the last output from the client as a String.
void	initialize(PipeMapRed pipeMapRed) Initializes the OutputReader.
abstract boolean	readKeyValue() Read the next key/value pair outputted by the client.

Methods inherited from class java.lang.Object

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

Constructor Detail

OutputReader

public OutputReader()

Method Detail

initialize

public void initialize(PipeMapRed pipeMapRed)
                throws IOException

Initializes the OutputReader. This method has to be called before calling any of the other methods.

Throws:

IOException

readKeyValue

public abstract boolean readKeyValue()
                              throws IOException

Read the next key/value pair outputted by the client.

Returns:

true iff a key/value pair was read

Throws:

IOException

getCurrentKey

public abstract K getCurrentKey()
                         throws IOException

Returns the current key.

Throws:

IOException

getCurrentValue

public abstract V getCurrentValue()
                           throws IOException

Returns the current value.

Throws:

IOException

getLastOutput

public abstract String getLastOutput()

Returns the last output from the client as a String.