假设我有一个利用Executor框架的应用程序
Executors.newSingleThreadExecutor().submit(new Runnable(){
@Override
public void run(){
// do stuff
}
}
当我在调试器中运行此应用程序时，将创建一个具有以下(默认)名称的线程:thread [pool-1-thread-1]。正如您所看到的，这并不是非常有用，而且据我所知，Executor框架并没有提供一种简单的方法来命名创建的线程或线程池。
那么，如何为线程/线程池提供名称呢?例如，Thread[fopool - foothread]。
当前回答
这是我的定制工厂，为线程转储分析器提供定制名称。通常我只是给tf=null来重用JVM默认的线程工厂。本网站有比较先进的螺纹工厂。
public class SimpleThreadFactory implements ThreadFactory {
private ThreadFactory tf;
private String nameSuffix;
public SimpleThreadFactory (ThreadFactory tf, String nameSuffix) {
this.tf = tf!=null ? tf : Executors.defaultThreadFactory();
this.nameSuffix = nameSuffix;
}
@Override public Thread newThread(Runnable task) {
// default "pool-1-thread-1" to "pool-1-thread-1-myapp-MagicTask"
Thread thread=tf.newThread(task);
thread.setName(thread.getName()+"-"+nameSuffix);
return thread;
}
}
- - - - -
ExecutorService es = Executors.newFixedThreadPool(4, new SimpleThreadFactory(null, "myapp-MagicTask") );
为了方便起见，这是一个用于调试的线程转储循环。
ThreadMXBean mxBean=ManagementFactory.getThreadMXBean();
long[] tids = mxBean.getAllThreadIds();
System.out.println("------------");
System.out.println("ThreadCount="+tids.length);
for(long tid : tids) {
ThreadInfo mxInfo=mxBean.getThreadInfo(tid);
if (mxInfo==null) {
System.out.printf("%d %s\n", tid, "Thread not found");
} else {
System.out.printf("%d %s, state=%s, suspended=%d, lockowner=%d %s\n"
, mxInfo.getThreadId(), mxInfo.getThreadName()
, mxInfo.getThreadState().toString()
, mxInfo.isSuspended()?1:0
, mxInfo.getLockOwnerId(), mxInfo.getLockOwnerName()
);
}
}
其他回答
apache common -lang中的BasicThreadFactory在提供命名行为方面也很有用。您可以使用Builder根据需要命名线程，而不是编写匿名的内部类。下面是来自javadocs的例子:
// Create a factory that produces daemon threads with a naming pattern and
// a priority
BasicThreadFactory factory = new BasicThreadFactory.Builder()
.namingPattern("workerthread-%d")
.daemon(true)
.priority(Thread.MAX_PRIORITY)
.build();
// Create an executor service for single-threaded execution
ExecutorService exec = Executors.newSingleThreadExecutor(factory);
这是我的定制工厂，为线程转储分析器提供定制名称。通常我只是给tf=null来重用JVM默认的线程工厂。本网站有比较先进的螺纹工厂。
public class SimpleThreadFactory implements ThreadFactory {
private ThreadFactory tf;
private String nameSuffix;
public SimpleThreadFactory (ThreadFactory tf, String nameSuffix) {
this.tf = tf!=null ? tf : Executors.defaultThreadFactory();
this.nameSuffix = nameSuffix;
}
@Override public Thread newThread(Runnable task) {
// default "pool-1-thread-1" to "pool-1-thread-1-myapp-MagicTask"
Thread thread=tf.newThread(task);
thread.setName(thread.getName()+"-"+nameSuffix);
return thread;
}
}
- - - - -
ExecutorService es = Executors.newFixedThreadPool(4, new SimpleThreadFactory(null, "myapp-MagicTask") );
为了方便起见，这是一个用于调试的线程转储循环。
ThreadMXBean mxBean=ManagementFactory.getThreadMXBean();
long[] tids = mxBean.getAllThreadIds();
System.out.println("------------");
System.out.println("ThreadCount="+tids.length);
for(long tid : tids) {
ThreadInfo mxInfo=mxBean.getThreadInfo(tid);
if (mxInfo==null) {
System.out.printf("%d %s\n", tid, "Thread not found");
} else {
System.out.printf("%d %s, state=%s, suspended=%d, lockowner=%d %s\n"
, mxInfo.getThreadId(), mxInfo.getThreadName()
, mxInfo.getThreadState().toString()
, mxInfo.isSuspended()?1:0
, mxInfo.getLockOwnerId(), mxInfo.getLockOwnerName()
);
}
}
您可以编写自己的ThreadFactory实现，例如使用一些现有的实现(如defaultThreadFactory)，并在最后更改名称。
实现ThreadFactory的例子:
class ThreadFactoryWithCustomName implements ThreadFactory {
private final ThreadFactory threadFactory;
private final String name;
public ThreadFactoryWithCustomName(final ThreadFactory threadFactory, final String name) {
this.threadFactory = threadFactory;
this.name = name;
}
@Override
public Thread newThread(final Runnable r) {
final Thread thread = threadFactory.newThread(r);
thread.setName(name);
return thread;
}
}
和用法:
Executors.newSingleThreadExecutor(new ThreadFactoryWithCustomName(
Executors.defaultThreadFactory(),
"customName")
);
正如其他答案已经说过的，您可以创建并使用自己的java.util.concurrent.ThreadFactory接口的实现(不需要外部库)。 我把我的代码粘贴在下面，因为它不同于以前的答案，因为它使用字符串。Format方法，并将线程的基名称作为构造函数参数:
import java.util.concurrent.ThreadFactory;
public class NameableThreadFactory implements ThreadFactory{
private int threadsNum;
private final String namePattern;
public NameableThreadFactory(String baseName){
namePattern = baseName + "-%d";
}
@Override
public Thread newThread(Runnable runnable){
threadsNum++;
return new Thread(runnable, String.format(namePattern, threadsNum));
}
}
这是一个用法的例子:
ThreadFactory threadFactory = new NameableThreadFactory("listenerThread");
final ExecutorService executorService = Executors.newFixedThreadPool(5, threadFactory);
编辑:使我的ThreadFactory实现线程安全，感谢@mchernyakov指出这一点。 尽管在ThreadFactory文档中没有任何地方说它的实现必须是线程安全的，但DefaultThreadFactory是线程安全的事实是一个很大的提示:
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.atomic.AtomicInteger;
public class NameableThreadFactory implements ThreadFactory{
private final AtomicInteger threadsNum = new AtomicInteger();
private final String namePattern;
public NameableThreadFactory(String baseName){
namePattern = baseName + "-%d";
}
@Override
public Thread newThread(Runnable runnable){
return new Thread(runnable, String.format(namePattern, threadsNum.addAndGet(1)));
}
}
你可以提供一个ThreadFactory给newSingleThreadScheduledExecutor(ThreadFactory)。工厂将负责创建线程，并能够为它们命名。
引用Javadoc的话:
Creating new threads New threads are created using a ThreadFactory. If not otherwise specified, a Executors.defaultThreadFactory() is used, that creates threads to all be in the same ThreadGroup and with the same NORM_PRIORITY priority and non-daemon status. By supplying a different ThreadFactory, you can alter the thread's name, thread group, priority, daemon status, etc. If a ThreadFactory fails to create a thread when asked by returning null from newThread, the executor will continue, but might not be able to execute any tasks
