/*
* Licensed to Elastic Search and Shay Banon under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. Elastic Search licenses this
* file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.elasticsearch.common.lucene.store;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.IndexInput;
import org.apache.lucene.store.IndexOutput;
import org.elasticsearch.common.collect.ImmutableSet;
import org.elasticsearch.index.store.support.ForceSyncDirectory;
import java.io.IOException;
import java.util.*;
/**
* A Directory instance that switches files between
* two other Directory instances.
*
* <p>Files with the specified extensions are placed in the
* primary directory; others are placed in the secondary
* directory.
*
* @author kimchy (shay.banon)
*/
public class SwitchDirectory extends Directory implements ForceSyncDirectory {
private final Directory secondaryDir;
private final Directory primaryDir;
private final ImmutableSet<String> primaryExtensions;
private boolean doClose;
public SwitchDirectory(Set<String> primaryExtensions, Directory primaryDir, Directory secondaryDir, boolean doClose) {
this.primaryExtensions = ImmutableSet.copyOf(primaryExtensions);
this.primaryDir = primaryDir;
this.secondaryDir = secondaryDir;
this.doClose = doClose;
this.lockFactory = primaryDir.getLockFactory();
}
public ImmutableSet<String> primaryExtensions() {
return primaryExtensions;
}
/**
* Return the primary directory
*/
public Directory primaryDir() {
return primaryDir;
}
/**
* Return the secondary directory
*/
public Directory secondaryDir() {
return secondaryDir;
}
@Override public void close() throws IOException {
if (doClose) {
try {
secondaryDir.close();
} finally {
primaryDir.close();
}
doClose = false;
}
}
@Override public String[] listAll() throws IOException {
Set<String> files = new HashSet<String>();
for (String f : primaryDir.listAll()) {
files.add(f);
}
for (String f : secondaryDir.listAll()) {
files.add(f);
}
return files.toArray(new String[files.size()]);
}
/**
* Utility method to return a file's extension.
*/
public static String getExtension(String name) {
int i = name.lastIndexOf('.');
if (i == -1) {
return "";
}
return name.substring(i + 1, name.length());
}
private Directory getDirectory(String name) {
String ext = getExtension(name);
if (primaryExtensions.contains(ext)) {
return primaryDir;
} else {
return secondaryDir;
}
}
@Override public boolean fileExists(String name) throws IOException {
return getDirectory(name).fileExists(name);
}
@Override public long fileModified(String name) throws IOException {
return getDirectory(name).fileModified(name);
}
@Override public void touchFile(String name) throws IOException {
getDirectory(name).touchFile(name);
}
@Override public void deleteFile(String name) throws IOException {
getDirectory(name).deleteFile(name);
}
@Override public long fileLength(String name) throws IOException {
return getDirectory(name).fileLength(name);
}
@Override public IndexOutput createOutput(String name) throws IOException {
return getDirectory(name).createOutput(name);
}
@Override public void sync(Collection<String> names) throws IOException {
List<String> primaryNames = new ArrayList<String>();
List<String> secondaryNames = new ArrayList<String>();
for (String name : names)
if (primaryExtensions.contains(getExtension(name)))
primaryNames.add(name);
else
secondaryNames.add(name);
primaryDir.sync(primaryNames);
secondaryDir.sync(secondaryNames);
}
@Override public void sync(String name) throws IOException {
getDirectory(name).sync(name);
}
@Override public void forceSync(String name) throws IOException {
Directory dir = getDirectory(name);
if (dir instanceof ForceSyncDirectory) {
((ForceSyncDirectory) dir).forceSync(name);
} else {
dir.sync(name);
}
}
@Override public IndexInput openInput(String name) throws IOException {
return getDirectory(name).openInput(name);
}
}