/*******************************************************************************
* Copyright (c) 2016 Zend Technologies and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* Zend Technologies - initial API and implementation
*******************************************************************************/
package org.eclipse.dltk.internal.core.index.lucene;
import java.io.FileOutputStream;
import java.io.FilterOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.nio.file.Path;
import java.text.MessageFormat;
import java.util.concurrent.Future;
import org.apache.lucene.store.FSDirectory;
import org.apache.lucene.store.IOContext;
import org.apache.lucene.store.IndexOutput;
import org.apache.lucene.store.LockFactory;
import org.apache.lucene.store.OutputStreamIndexOutput;
import org.apache.lucene.store.RAFDirectory;
/**
* <p>
* Default directory implementation that store index files in the file system.
* </p>
* <p>
* This extended implementation of {@link RAFDirectory} prevents from abnormal
* index closing in case of interrupting indexing/searching threads via
* {@link Thread#interrupt()} or {@link Future#cancel(boolean)}. As RAFDirectory
* itself is using {@link FSDirectory.FSIndexOutput} that is vulnerable to
* thread interruption, this implementation provides additional
* {@link RAFIndexOutput} as a safe substitution.
* </p>
*
* @author Bartlomiej Laczkowski
*/
public class IndexDirectory extends RAFDirectory {
final class RAFIndexOutput extends OutputStreamIndexOutput {
private static final int CHUNK_SIZE = 8192;
private static final String DESCRIPTION = "RAFIndexOutput(path=\"{0}\")"; //$NON-NLS-1$
public RAFIndexOutput(String name) throws IOException {
super(MessageFormat.format(DESCRIPTION, directory.resolve(name)),
name,
new RAFOutputStream(
new FileOutputStream(
directory.resolve(name).toFile()),
CHUNK_SIZE),
CHUNK_SIZE);
}
}
final static class RAFOutputStream extends FilterOutputStream {
final private int fChunkSize;
public RAFOutputStream(OutputStream out, int chunkSize) {
super(out);
fChunkSize = chunkSize;
}
@Override
public void write(byte[] b, int offset, int length) throws IOException {
while (length > 0) {
final int chunk = Math.min(length, fChunkSize);
out.write(b, offset, chunk);
length -= chunk;
offset += chunk;
}
}
}
public IndexDirectory(Path path) throws IOException {
super(path);
}
public IndexDirectory(Path path, LockFactory lockFactory)
throws IOException {
super(path, lockFactory);
}
@Override
public IndexOutput createOutput(String name, IOContext context)
throws IOException {
ensureOpen();
return new RAFIndexOutput(name);
}
}