/*
* 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.mina.common;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.Executor;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.atomic.AtomicInteger;
import org.apache.mina.filter.executor.ExecutorFilter;
/**
* A {@link ThreadModel} which represents a thread model with an {@link Executor}
* per service. The default underlying {@link Executor} is {@link ThreadPoolExecutor},
* so you can safely downcast the returned {@link Executor} of {@link #getExecutor()} to
* {@link ThreadPoolExecutor} by default.
*
* @author The Apache Directory Project (mina-dev@directory.apache.org)
* @version $Rev: 555855 $, $Date: 2007-07-13 12:19:00 +0900 (Fri, 13 Jul 2007) $
*/
public class ExecutorThreadModel implements ThreadModel {
/**
* Maps a service name to a PooledThreadModel instance.
* Without this map, we might create extremely many thread pools that leads the system to
* coma. */
private static final Map<String, ExecutorThreadModel> service2model = new HashMap<String, ExecutorThreadModel>();
/**
* Returns a {@link ExecutorThreadModel} instance for the specified <tt>serviceName</tt>.
* Please note that all returned instances will be managed globally; the same instance
* will be returned if you specified the same service name. Please try to specify
* different names for different services.
*
* @param serviceName the name of the service that needs thread pooling
*/
public static ExecutorThreadModel getInstance(String serviceName) {
if (serviceName == null) {
throw new NullPointerException("serviceName");
}
ExecutorThreadModel model;
synchronized (service2model) {
model = service2model.get(serviceName);
if (model == null) {
model = new ExecutorThreadModel(serviceName);
service2model.put(serviceName, model);
}
}
return model;
}
private final String threadNamePrefix;
private final ExecutorFilter defaultFilter;
private ExecutorFilter filter = new ExecutorFilter();
private ExecutorThreadModel(String threadNamePrefix) {
this.threadNamePrefix = threadNamePrefix;
// Create the default filter
defaultFilter = new ExecutorFilter();
ThreadPoolExecutor tpe = (ThreadPoolExecutor) defaultFilter
.getExecutor();
final ThreadFactory originalThreadFactory = tpe.getThreadFactory();
ThreadFactory newThreadFactory = new ThreadFactory() {
private final AtomicInteger threadId = new AtomicInteger(0);
public Thread newThread(Runnable runnable) {
Thread t = originalThreadFactory.newThread(runnable);
t.setName(ExecutorThreadModel.this.threadNamePrefix + '-'
+ threadId.incrementAndGet());
t.setDaemon(true);
return t;
}
};
tpe.setThreadFactory(newThreadFactory);
// Set to default.
setExecutor(null);
}
/**
* Returns the underlying {@link Executor} of this model.
* You can change various properties such as the number of threads
* by calling methods of the {@link Executor} implementation.
*/
public Executor getExecutor() {
return filter.getExecutor();
}
/**
* Changes the underlying {@link Executor} of this model.
* Previous settings such as the number of threads should be configured again.
* Only newly created {@link IoSession}s will be affected.
*
* @param executor <tt>null</tt> to revert to the default setting
*/
public void setExecutor(Executor executor) {
if (executor == null) {
filter = defaultFilter;
} else {
filter = new ExecutorFilter(executor);
}
}
public void buildFilterChain(IoFilterChain chain) throws Exception {
chain.addFirst(ExecutorThreadModel.class.getName(), filter);
}
}