org.apache.hadoop.mapred

Class LineRecordReader

java.lang.Object

org.apache.hadoop.mapred.LineRecordReader

All Implemented Interfaces:

RecordReader<LongWritable,Text>

@InterfaceAudience.LimitedPrivate(value={"MapReduce","Pig"})
@InterfaceStability.Unstable
public class LineRecordReader
extends Object
implements RecordReader<LongWritable,Text>

Treats keys as offset in file and value as line.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	LineRecordReader.LineReader Deprecated. Use LineReader instead.

Constructor Summary

Constructors

Constructor and Description
LineRecordReader(Configuration job, FileSplit split)
LineRecordReader(Configuration job, FileSplit split, byte[] recordDelimiter)
LineRecordReader(InputStream in, long offset, long endOffset, Configuration job)
LineRecordReader(InputStream in, long offset, long endOffset, Configuration job, byte[] recordDelimiter)
LineRecordReader(InputStream in, long offset, long endOffset, int maxLineLength)
LineRecordReader(InputStream in, long offset, long endOffset, int maxLineLength, byte[] recordDelimiter)

Method Summary

Methods

Modifier and Type	Method and Description
void	close() Close this InputSplit to future operations.
LongWritable	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() Get the progress within the split
boolean	next(LongWritable key, Text value) Read a line.

Methods inherited from class java.lang.Object

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

Constructor Detail

LineRecordReader

public LineRecordReader(Configuration job,
                FileSplit split)
                 throws IOException

Throws:

IOException

LineRecordReader

public LineRecordReader(Configuration job,
                FileSplit split,
                byte[] recordDelimiter)
                 throws IOException

Throws:

IOException

LineRecordReader

public LineRecordReader(InputStream in,
                long offset,
                long endOffset,
                int maxLineLength)

LineRecordReader

public LineRecordReader(InputStream in,
                long offset,
                long endOffset,
                int maxLineLength,
                byte[] recordDelimiter)

LineRecordReader

public LineRecordReader(InputStream in,
                long offset,
                long endOffset,
                Configuration job)
                 throws IOException

Throws:

IOException

LineRecordReader

public LineRecordReader(InputStream in,
                long offset,
                long endOffset,
                Configuration job,
                byte[] recordDelimiter)
                 throws IOException

Throws:

IOException

Method Detail

createKey

public LongWritable 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<LongWritable,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<LongWritable,Text>

Returns:

a new value object.

next

public boolean next(LongWritable key,
           Text value)
             throws IOException

Read a line.

Specified by:

next in interface RecordReader<LongWritable,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

getProgress

public float getProgress()
                  throws IOException

Get the progress within the split

Specified by:

getProgress in interface RecordReader<LongWritable,Text>

Returns:

progress from 0.0 to 1.0.

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<LongWritable,Text>

Returns:

the current position in the input.

Throws:

IOException

close

public void close()
           throws IOException

Description copied from interface: RecordReader

Close this InputSplit to future operations.

Specified by:

close in interface RecordReader<LongWritable,Text>

Throws:

IOException