/* * Copyright (c) 2008, 2009, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */package sun.nio.ch;import java.util.concurrent.*;import java.security.AccessController;import sun.security.action.GetPropertyAction;import sun.security.action.GetIntegerAction;/** * Encapsulates a thread pool associated with a channel group. */public class ThreadPool { private static final String DEFAULT_THREAD_POOL_THREAD_FACTORY = "java.nio.channels.DefaultThreadPool.threadFactory"; private static final String DEFAULT_THREAD_POOL_INITIAL_SIZE = "java.nio.channels.DefaultThreadPool.initialSize"; private static final ThreadFactory defaultThreadFactory = new ThreadFactory() { @Override public Thread newThread(Runnable r) { Thread t = new Thread(r); t.setDaemon(true); return t; } }; private final ExecutorService executor; // indicates if thread pool is fixed size private final boolean isFixed; // indicates the pool size (for a fixed thread pool configuratin this is // the maximum pool size; for other thread pools it is the initial size) private final int poolSize; private ThreadPool(ExecutorService executor, boolean isFixed, int poolSize) { this.executor = executor; this.isFixed = isFixed; this.poolSize = poolSize; } ExecutorService executor() { return executor; } boolean isFixedThreadPool() { return isFixed; } int poolSize() { return poolSize; } static ThreadFactory defaultThreadFactory() { return defaultThreadFactory; } private static class DefaultThreadPoolHolder { final static ThreadPool defaultThreadPool = createDefault(); } // return the default (system-wide) thread pool static ThreadPool getDefault() { return DefaultThreadPoolHolder.defaultThreadPool; } // create thread using default settings (configured by system properties) static ThreadPool createDefault() { // default the number of fixed threads to the hardware core count int initialSize = getDefaultThreadPoolInitialSize(); if (initialSize < 0) initialSize = Runtime.getRuntime().availableProcessors(); // default to thread factory that creates daemon threads ThreadFactory threadFactory = getDefaultThreadPoolThreadFactory(); if (threadFactory == null) threadFactory = defaultThreadFactory; // create thread pool ExecutorService executor = new ThreadPoolExecutor(0, Integer.MAX_VALUE, Long.MAX_VALUE, TimeUnit.MILLISECONDS, new SynchronousQueue<Runnable>(), threadFactory); return new ThreadPool(executor, false, initialSize); } // create using given parameters static ThreadPool create(int nThreads, ThreadFactory factory) { if (nThreads <= 0) throw new IllegalArgumentException("'nThreads' must be > 0"); ExecutorService executor = Executors.newFixedThreadPool(nThreads, factory); return new ThreadPool(executor, true, nThreads); } // wrap a user-supplied executor public static ThreadPool wrap(ExecutorService executor, int initialSize) { if (executor == null) throw new NullPointerException("'executor' is null"); // attempt to check if cached thread pool if (executor instanceof ThreadPoolExecutor) { int max = ((ThreadPoolExecutor)executor).getMaximumPoolSize(); if (max == Integer.MAX_VALUE) { if (initialSize < 0) { initialSize = Runtime.getRuntime().availableProcessors(); } else { // not a cached thread pool so ignore initial size initialSize = 0; } } } else { // some other type of thread pool if (initialSize < 0) initialSize = 0; } return new ThreadPool(executor, false, initialSize); } private static int getDefaultThreadPoolInitialSize() { String propValue = AccessController.doPrivileged(new GetPropertyAction(DEFAULT_THREAD_POOL_INITIAL_SIZE)); if (propValue != null) { try { return Integer.parseInt(propValue); } catch (NumberFormatException x) { throw new Error("Value of property '" + DEFAULT_THREAD_POOL_INITIAL_SIZE + "' is invalid: " + x); } } return -1; } private static ThreadFactory getDefaultThreadPoolThreadFactory() { String propValue = AccessController.doPrivileged(new GetPropertyAction(DEFAULT_THREAD_POOL_THREAD_FACTORY)); if (propValue != null) { try { Class<?> c = Class .forName(propValue, true, ClassLoader.getSystemClassLoader()); return ((ThreadFactory)c.newInstance()); } catch (ClassNotFoundException x) { throw new Error(x); } catch (InstantiationException x) { throw new Error(x); } catch (IllegalAccessException x) { throw new Error(x); } } return null; }}
/*
* Copyright (c) 2008, 2009, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package sun.nio.ch;
import java.util.concurrent.*;
import java.security.AccessController;
import sun.security.action.GetPropertyAction;
import sun.security.action.GetIntegerAction;
/**
* Encapsulates a thread pool associated with a channel group.
*/
public class ThreadPool {
private static final String DEFAULT_THREAD_POOL_THREAD_FACTORY =
"java.nio.channels.DefaultThreadPool.threadFactory";
private static final String DEFAULT_THREAD_POOL_INITIAL_SIZE =
"java.nio.channels.DefaultThreadPool.initialSize";
private static final ThreadFactory defaultThreadFactory = new ThreadFactory() {
@Override
public Thread newThread(Runnable r) {
Thread t = new Thread(r);
t.setDaemon(true);
return t;
}
};
private final ExecutorService executor;
// indicates if thread pool is fixed size
private final boolean isFixed;
// indicates the pool size (for a fixed thread pool configuratin this is
// the maximum pool size; for other thread pools it is the initial size)
private final int poolSize;
private ThreadPool(ExecutorService executor,
boolean isFixed,
int poolSize)
{
this.executor = executor;
this.isFixed = isFixed;
this.poolSize = poolSize;
}
ExecutorService executor() {
return executor;
}
boolean isFixedThreadPool() {
return isFixed;
}
int poolSize() {
return poolSize;
}
static ThreadFactory defaultThreadFactory() {
return defaultThreadFactory;
}
private static class DefaultThreadPoolHolder {
final static ThreadPool defaultThreadPool = createDefault();
}
// return the default (system-wide) thread pool
static ThreadPool getDefault() {
return DefaultThreadPoolHolder.defaultThreadPool;
}
// create thread using default settings (configured by system properties)
static ThreadPool createDefault() {
// default the number of fixed threads to the hardware core count
int initialSize = getDefaultThreadPoolInitialSize();
if (initialSize < 0)
initialSize = Runtime.getRuntime().availableProcessors();
// default to thread factory that creates daemon threads
ThreadFactory threadFactory = getDefaultThreadPoolThreadFactory();
if (threadFactory == null)
threadFactory = defaultThreadFactory;
// create thread pool
ExecutorService executor =
new ThreadPoolExecutor(0, Integer.MAX_VALUE,
Long.MAX_VALUE, TimeUnit.MILLISECONDS,
new SynchronousQueue<Runnable>(),
threadFactory);
return new ThreadPool(executor, false, initialSize);
}
// create using given parameters
static ThreadPool create(int nThreads, ThreadFactory factory) {
if (nThreads <= 0)
throw new IllegalArgumentException("'nThreads' must be > 0");
ExecutorService executor = Executors.newFixedThreadPool(nThreads, factory);
return new ThreadPool(executor, true, nThreads);
}
// wrap a user-supplied executor
public static ThreadPool wrap(ExecutorService executor, int initialSize) {
if (executor == null)
throw new NullPointerException("'executor' is null");
// attempt to check if cached thread pool
if (executor instanceof ThreadPoolExecutor) {
int max = ((ThreadPoolExecutor)executor).getMaximumPoolSize();
if (max == Integer.MAX_VALUE) {
if (initialSize < 0) {
initialSize = Runtime.getRuntime().availableProcessors();
} else {
// not a cached thread pool so ignore initial size
initialSize = 0;
}
}
} else {
// some other type of thread pool
if (initialSize < 0)
initialSize = 0;
}
return new ThreadPool(executor, false, initialSize);
}
private static int getDefaultThreadPoolInitialSize() {
String propValue = AccessController.doPrivileged(new
GetPropertyAction(DEFAULT_THREAD_POOL_INITIAL_SIZE));
if (propValue != null) {
try {
return Integer.parseInt(propValue);
} catch (NumberFormatException x) {
throw new Error("Value of property '" + DEFAULT_THREAD_POOL_INITIAL_SIZE +
"' is invalid: " + x);
}
}
return -1;
}
private static ThreadFactory getDefaultThreadPoolThreadFactory() {
String propValue = AccessController.doPrivileged(new
GetPropertyAction(DEFAULT_THREAD_POOL_THREAD_FACTORY));
if (propValue != null) {
try {
Class<?> c = Class
.forName(propValue, true, ClassLoader.getSystemClassLoader());
return ((ThreadFactory)c.newInstance());
} catch (ClassNotFoundException x) {
throw new Error(x);
} catch (InstantiationException x) {
throw new Error(x);
} catch (IllegalAccessException x) {
throw new Error(x);
}
}
return null;
}
}