com.sun.labs.minion.indexer.postings.io
Class FileBackedPostingsInput

java.lang.Object
  com.sun.labs.minion.util.buffer.StdReadableImpl
      com.sun.labs.minion.util.buffer.FileReadableBuffer
          com.sun.labs.minion.indexer.postings.io.FileBackedPostingsInput

All Implemented Interfaces:

PostingsInput, Buffer, ReadableBuffer

public class FileBackedPostingsInput
extends FileReadableBuffer
implements PostingsInput

A postings input that extends a file backed buffer. The postings that are returned are this buffer. This is useful in situations where we're iterating through a large portion of the postings for a file and the postings are not multipart (e.g., IDPostings).

Field Summary

protected static java.lang.String

logTag

Fields inherited from class com.sun.labs.minion.util.buffer.FileReadableBuffer

be, bs, buff, DEFAULT_BUFF_SIZE, me, ms, pos, raf

Constructor Summary

FileBackedPostingsInput(java.io.RandomAccessFile raf, long offset, int buffSize)

Method Summary

ReadableBuffer

read(long offset, int size) Reads a set of postings, returning them in a buffer suitable for decoding.

Methods inherited from class com.sun.labs.minion.util.buffer.FileReadableBuffer

checkBounds, duplicate, get, get, limit, limit, position, position, read, remaining, slice, toString

Methods inherited from class com.sun.labs.minion.util.buffer.StdReadableImpl

byteDecode, byteDecode, byteDecode, byteDecodeLong, byteDecodeLong, byteDecodeLong, countBits, decodeFloat, getString, skipByteEncoded, test, toString, toString

Methods inherited from class java.lang.Object

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

Field Detail

logTag

protected static java.lang.String logTag

Constructor Detail

FileBackedPostingsInput

public FileBackedPostingsInput(java.io.RandomAccessFile raf,
                               long offset,
                               int buffSize)
                        throws java.io.IOException

Throws:

java.io.IOException

Method Detail

read

public ReadableBuffer read(long offset,
                           int size)
                    throws java.io.IOException

Reads a set of postings, returning them in a buffer suitable for decoding. The buffer that is returned is backed by the file containing the postings.

Specified by:

read in interface PostingsInput

Parameters:

offset - The offset in the input at which the postings can be found.

size - The number of bytes to read to get the postings.

Returns:

A readable buffer containing the postings.

Throws:

java.io.IOException - if there is any error reading the postings.