org.apache.hadoop.io
Class ArrayFile.Reader

java.lang.Object
  extended by org.apache.hadoop.io.MapFile.Reader
      extended by 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.


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, 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


Copyright © 2009 The Apache Software Foundation