org.apache.avro.mapred
Class SequenceFileReader<K,V>

java.lang.Object
  org.apache.avro.mapred.SequenceFileReader<K,V>

All Implemented Interfaces:

Closeable, Iterable<Pair<K,V>>, Iterator<Pair<K,V>>, FileReader<Pair<K,V>>

public class SequenceFileReader<K,V>
extends Object
implements FileReader<Pair<K,V>>

A FileReader for sequence files.

Constructor Summary

SequenceFileReader(File file)

SequenceFileReader(SequenceFile.Reader reader, Configuration conf)

SequenceFileReader(URI uri, Configuration c)

Method Summary

void	close()
Schema	getSchema() Return the schema for data in this file.
boolean	hasNext()
Iterator<Pair<K,V>>	iterator()
Pair<K,V>	next()
Pair<K,V>	next(Pair<K,V> reuse) Read the next datum from the file.
boolean	pastSync(long position) Return true if past the next synchronization point after a position.
void	remove()
void	sync(long position) Move to the next synchronization point after a position.
long	tell() Return the current position in the input.

Methods inherited from class java.lang.Object

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

Constructor Detail

SequenceFileReader

public SequenceFileReader(File file)
                   throws IOException

Throws:

IOException

SequenceFileReader

public SequenceFileReader(URI uri,
                          Configuration c)
                   throws IOException

Throws:

IOException

SequenceFileReader

public SequenceFileReader(SequenceFile.Reader reader,
                          Configuration conf)

Method Detail

close

public void close()
           throws IOException

Specified by:

close in interface Closeable

Throws:

IOException

remove

public void remove()

Specified by:

remove in interface Iterator<Pair<K,V>>

iterator

public Iterator<Pair<K,V>> iterator()

Specified by:

iterator in interface Iterable<Pair<K,V>>

getSchema

public Schema getSchema()

Description copied from interface: FileReader

Return the schema for data in this file.

Specified by:

getSchema in interface FileReader<Pair<K,V>>

hasNext

public boolean hasNext()

Specified by:

hasNext in interface Iterator<Pair<K,V>>

next

public Pair<K,V> next()

Specified by:

next in interface Iterator<Pair<K,V>>

next

public Pair<K,V> next(Pair<K,V> reuse)
               throws IOException

Description copied from interface: FileReader

Read the next datum from the file.

Specified by:

next in interface FileReader<Pair<K,V>>

Parameters:

reuse - an instance to reuse.

Throws:

IOException

sync

public void sync(long position)
          throws IOException

Description copied from interface: FileReader

Move to the next synchronization point after a position. To process a range of file entires, call this with the starting position, then check FileReader.pastSync(long) with the end point before each call to Iterator.next().

Specified by:

sync in interface FileReader<Pair<K,V>>

Throws:

IOException

pastSync

public boolean pastSync(long position)
                 throws IOException

Description copied from interface: FileReader

Return true if past the next synchronization point after a position.

Specified by:

pastSync in interface FileReader<Pair<K,V>>

Throws:

IOException

tell

public long tell()
          throws IOException

Description copied from interface: FileReader

Return the current position in the input.

Specified by:

tell in interface FileReader<Pair<K,V>>

Throws:

IOException