eu.stratosphere.nephele.taskmanager.bytebuffered.CanceledChannelSet Maven / Gradle / Ivy
/***********************************************************************************************************************
* Copyright (C) 2010-2013 by the Stratosphere project (http://stratosphere.eu)
*
* Licensed 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 eu.stratosphere.nephele.taskmanager.bytebuffered;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import eu.stratosphere.nephele.io.channels.ChannelID;
/**
* This channel set stores the ID's of all channels whose tasks have been canceled recently. The set is cleaned up by
* periodically calling the method cleanup.
*
* This class is thread-safe.
*
*/
public final class CanceledChannelSet implements Set {
/**
* The period of time the entries must at least remain in the map.
*/
private final static long CLEANUP_INTERVAL = 30000; // 30 sec.
/**
* The map which stores the ID's of the channels whose tasks have been canceled.
*/
private final Map canceledChannels = new HashMap();
@Override
public boolean add(ChannelID arg0) {
final long now = System.currentTimeMillis();
synchronized (this.canceledChannels) {
if (this.canceledChannels.put(arg0, Long.valueOf(now)) == null) {
return true;
}
}
return false;
}
@Override
public boolean addAll(Collection arg0) {
final Long now = Long.valueOf(System.currentTimeMillis());
final Iterator it = arg0.iterator();
boolean retVal = false;
synchronized (this.canceledChannels) {
while (it.hasNext()) {
if (this.canceledChannels.put(it.next(), now) == null) {
retVal = true;
}
}
}
return retVal;
}
@Override
public void clear() {
synchronized (this.canceledChannels) {
this.canceledChannels.clear();
}
}
@Override
public boolean contains(Object arg0) {
synchronized (this.canceledChannels) {
return this.canceledChannels.containsKey(arg0);
}
}
@Override
public boolean containsAll(Collection arg0) {
synchronized (this.canceledChannels) {
return this.canceledChannels.keySet().containsAll(arg0);
}
}
@Override
public boolean isEmpty() {
synchronized (this.canceledChannels) {
return this.canceledChannels.isEmpty();
}
}
@Override
public Iterator iterator() {
synchronized (this.canceledChannels) {
return this.canceledChannels.keySet().iterator();
}
}
@Override
public boolean remove(Object arg0) {
synchronized (this.canceledChannels) {
if (this.canceledChannels.remove(arg0) == null) {
return false;
}
}
return true;
}
@Override
public boolean removeAll(Collection arg0) {
final Iterator it = arg0.iterator();
boolean retVal = false;
synchronized (this.canceledChannels) {
while (it.hasNext()) {
if (this.canceledChannels.remove(it.next()) != null) {
retVal = true;
}
}
}
return retVal;
}
@Override
public boolean retainAll(Collection arg0) {
throw new RuntimeException("Method not implemented");
}
@Override
public int size() {
synchronized (this.canceledChannels) {
return this.canceledChannels.size();
}
}
@Override
public Object[] toArray() {
synchronized (this.canceledChannels) {
return this.canceledChannels.keySet().toArray();
}
}
@Override
public T[] toArray(T[] arg0) {
synchronized (this.canceledChannels) {
return this.canceledChannels.keySet().toArray(arg0);
}
}
/**
* Removes all entries from the set which have been added longer than CLEANUP_INTERVAL milliseconds
* ago.
*/
public void cleanup() {
final long now = System.currentTimeMillis();
synchronized (this.canceledChannels) {
final Iterator> it = this.canceledChannels.entrySet().iterator();
while (it.hasNext()) {
final Map.Entry entry = it.next();
if ((entry.getValue().longValue() + CLEANUP_INTERVAL) < now) {
it.remove();
}
}
}
}
}