org.apache.hadoop.examples
Class MultiFileWordCount.MultiFileLineRecordReader

java.lang.Object
  org.apache.hadoop.examples.MultiFileWordCount.MultiFileLineRecordReader

All Implemented Interfaces:

RecordReader<MultiFileWordCount.WordOffset,Text>

Enclosing class:

MultiFileWordCount

public static class MultiFileWordCount.MultiFileLineRecordReader
extends Object
implements RecordReader<MultiFileWordCount.WordOffset,Text>

RecordReader is responsible from extracting records from the InputSplit. This record reader accepts a MultiFileSplit, which encapsulates several files, and no file is divided.

Constructor Summary

MultiFileWordCount.MultiFileLineRecordReader(Configuration conf, MultiFileSplit split)

Method Summary

void	close() Close this InputSplit to future operations.
MultiFileWordCount.WordOffset	createKey() Create an object of the appropriate type to be used as a key.
Text	createValue() Create an object of the appropriate type to be used as a value.
long	getPos() Returns the current position in the input.
float	getProgress() How much of the input has the RecordReader consumed i.e.
boolean	next(MultiFileWordCount.WordOffset key, Text value) Reads the next key/value pair from the input for processing.

Methods inherited from class java.lang.Object

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

Constructor Detail

MultiFileWordCount.MultiFileLineRecordReader

public MultiFileWordCount.MultiFileLineRecordReader(Configuration conf,
                                                    MultiFileSplit split)
                                             throws IOException

Throws:

IOException

Method Detail

close

public void close()
           throws IOException

Description copied from interface: RecordReader

Close this InputSplit to future operations.

Specified by:

close in interface RecordReader<MultiFileWordCount.WordOffset,Text>

Throws:

IOException

getPos

public long getPos()
            throws IOException

Description copied from interface: RecordReader

Returns the current position in the input.

Specified by:

getPos in interface RecordReader<MultiFileWordCount.WordOffset,Text>

Returns:

the current position in the input.

Throws:

IOException

getProgress

public float getProgress()
                  throws IOException

Description copied from interface: RecordReader

How much of the input has the RecordReader consumed i.e. has been processed by?

Specified by:

getProgress in interface RecordReader<MultiFileWordCount.WordOffset,Text>

Returns:

progress from 0.0 to 1.0.

Throws:

IOException

next

public boolean next(MultiFileWordCount.WordOffset key,
                    Text value)
             throws IOException

Description copied from interface: RecordReader

Reads the next key/value pair from the input for processing.

Specified by:

next in interface RecordReader<MultiFileWordCount.WordOffset,Text>

Parameters:

key - the key to read data into

value - the value to read data into

Returns:

true iff a key/value was read, false if at EOF

Throws:

IOException

createKey

public MultiFileWordCount.WordOffset createKey()

Description copied from interface: RecordReader

Create an object of the appropriate type to be used as a key.

Specified by:

createKey in interface RecordReader<MultiFileWordCount.WordOffset,Text>

Returns:

a new key object.

createValue

public Text createValue()

Description copied from interface: RecordReader

Create an object of the appropriate type to be used as a value.

Specified by:

createValue in interface RecordReader<MultiFileWordCount.WordOffset,Text>

Returns:

a new value object.