gate.creole.annic.apache.lucene.index
Class CompoundFileWriter

java.lang.Object
  gate.creole.annic.apache.lucene.index.CompoundFileWriter

final class CompoundFileWriter
extends Object

Combines multiple files into a single compound file. The file format:

• VInt fileCount
• {Directory} fileCount entries with the following structure:
• long dataOffset
• UTFString extension
• {File Data} fileCount entries with the raw data of the corresponding file

The fileCount integer indicates how many files are contained in this compound file. The {directory} that follows has that many entries. Each directory entry contains an encoding identifier, an long pointer to the start of this file's data section, and a UTF String with that file's extension.

Version:

$Id: CompoundFileWriter.java 529 2004-10-05 11:55:26Z niraj $

Author:

Dmitry Serebrennikov

Nested Class Summary

private static class

CompoundFileWriter.FileEntry

Field Summary

private Directory	directory
private LinkedList	entries
private String	fileName
private HashSet	ids
private boolean	merged

Constructor Summary

CompoundFileWriter(Directory dir, String name)
Create the compound stream in the specified file.

Method Summary

void	addFile(String file) Add a source stream.
void	close() Merge files with the extensions added up to now.
private void	copyFile(CompoundFileWriter.FileEntry source, OutputStream os, byte[] buffer) Copy the contents of the file with specified extension into the provided output stream.
Directory	getDirectory() Returns the directory of the compound file.
String	getName() Returns the name of the compound file.

Methods inherited from class java.lang.Object

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

Field Detail

directory

private Directory directory

fileName

private String fileName

ids

private HashSet ids

entries

private LinkedList entries

merged

private boolean merged

Constructor Detail

CompoundFileWriter

public CompoundFileWriter(Directory dir,
                          String name)

Create the compound stream in the specified file. The file name is the entire name (no extensions are added).

Method Detail

getDirectory

public Directory getDirectory()

Returns the directory of the compound file.

getName

public String getName()

Returns the name of the compound file.

addFile

public void addFile(String file)

Add a source stream. If sourceDir is null, it is set to the same value as the directory where this compound stream exists. The id is the string by which the sub-stream will be know in the compound stream. The caller must ensure that the ID is unique. If the id is null, it is set to the name of the source file.

close

public void close()
           throws IOException

Merge files with the extensions added up to now. All files with these extensions are combined sequentially into the compound stream. After successful merge, the source files are deleted.

Throws:

IOException

copyFile

private void copyFile(CompoundFileWriter.FileEntry source,
                      OutputStream os,
                      byte[] buffer)
               throws IOException

Copy the contents of the file with specified extension into the provided output stream. Use the provided buffer for moving data to reduce memory allocation.

Throws:

IOException