/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF 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.apache.solr.util;
import java.io.File;
import java.lang.ref.PhantomReference;
import java.lang.ref.ReferenceQueue;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import org.apache.commons.io.FileCleaningTracker;
import org.apache.commons.io.FileDeleteStrategy;
public class SolrFileCleaningTracker extends FileCleaningTracker {
ReferenceQueue<Object> q = new ReferenceQueue<>();
final Collection<Tracker> trackers = Collections.synchronizedSet(new HashSet<Tracker>());
final List<String> deleteFailures = Collections.synchronizedList(new ArrayList<String>());
volatile boolean exitWhenFinished = false;
Thread reaper;
public void track(final File file, final Object marker) {
track(file, marker, null);
}
public void track(final File file, final Object marker, final FileDeleteStrategy deleteStrategy) {
if (file == null) {
throw new NullPointerException("The file must not be null");
}
addTracker(file.getPath(), marker, deleteStrategy);
}
public void track(final String path, final Object marker) {
track(path, marker, null);
}
public void track(final String path, final Object marker, final FileDeleteStrategy deleteStrategy) {
if (path == null) {
throw new NullPointerException("The path must not be null");
}
addTracker(path, marker, deleteStrategy);
}
private synchronized void addTracker(final String path, final Object marker,
final FileDeleteStrategy deleteStrategy) {
if (exitWhenFinished) {
throw new IllegalStateException("No new trackers can be added once exitWhenFinished() is called");
}
if (reaper == null) {
reaper = new Reaper();
reaper.start();
}
trackers.add(new Tracker(path, deleteStrategy, marker, q));
}
public int getTrackCount() {
return trackers.size();
}
public List<String> getDeleteFailures() {
return deleteFailures;
}
public synchronized void exitWhenFinished() {
// synchronized block protects reaper
exitWhenFinished = true;
if (reaper != null) {
synchronized (reaper) {
reaper.interrupt();
try {
reaper.join();
} catch (InterruptedException e) {
Thread.currentThread().interrupt();
}
}
}
}
private final class Reaper extends Thread {
Reaper() {
super("MultiPart Upload Tmp File Reaper");
setDaemon(true);
}
@Override
public void run() {
while (exitWhenFinished == false || trackers.size() > 0) {
try {
// Wait for a tracker to remove.
final Tracker tracker = (Tracker) q.remove(); // cannot return null
trackers.remove(tracker);
if (!tracker.delete()) {
deleteFailures.add(tracker.getPath());
}
tracker.clear();
} catch (final InterruptedException e) {
Thread.currentThread().interrupt();
break;
}
}
}
}
private static final class Tracker extends PhantomReference<Object> {
private final String path;
private final FileDeleteStrategy deleteStrategy;
Tracker(final String path, final FileDeleteStrategy deleteStrategy, final Object marker,
final ReferenceQueue<? super Object> queue) {
super(marker, queue);
this.path = path;
this.deleteStrategy = deleteStrategy == null ? FileDeleteStrategy.NORMAL : deleteStrategy;
}
public String getPath() {
return path;
}
public boolean delete() {
return deleteStrategy.deleteQuietly(new File(path));
}
}
}