org.apache.hadoop.io
Class ArrayFile.Reader

java.lang.Object
  org.apache.hadoop.io.MapFile.Reader
      org.apache.hadoop.io.ArrayFile.Reader

All Implemented Interfaces:

Closeable

Enclosing class:

ArrayFile

public static class ArrayFile.Reader
extends MapFile.Reader

Provide access to an existing array file.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.hadoop.io.MapFile.Reader

MapFile.Reader.Option

Constructor Summary

ArrayFile.Reader(FileSystem fs, String file, Configuration conf)
Construct an array reader for the named file.

Method Summary

Writable	get(long n, Writable value) Return the nth value in the file.
long	key() Returns the key associated with the most recent call to seek(long), next(Writable), or get(long,Writable).
Writable	next(Writable value) Read and return the next value in the file.
void	seek(long n) Positions the reader before its nth value.

Methods inherited from class org.apache.hadoop.io.MapFile.Reader

close, comparator, createDataFileReader, finalKey, get, getClosest, getClosest, getKeyClass, getValueClass, midKey, next, open, reset, seek

Methods inherited from class java.lang.Object

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

Constructor Detail

ArrayFile.Reader

public ArrayFile.Reader(FileSystem fs,
                        String file,
                        Configuration conf)
                 throws IOException

Construct an array reader for the named file.

Throws:

IOException

Method Detail

seek

public void seek(long n)
          throws IOException

Positions the reader before its nth value.

Throws:

IOException

next

public Writable next(Writable value)
              throws IOException

Read and return the next value in the file.

Throws:

IOException

key

public long key()
         throws IOException

Returns the key associated with the most recent call to seek(long), next(Writable), or get(long,Writable).

Throws:

IOException

get

public Writable get(long n,
                    Writable value)
             throws IOException

Return the nth value in the file.

Throws:

IOException