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]。
ThreadFactory扩展
公共接口
根据需要创建新线程的对象。使用线程工厂消除了对新线程的硬连接,使应用程序能够使用特殊的线程子类、优先级等。
线程newThread(可运行r)
构造一个新的线程。实现也可以初始化优先级、名称、守护进程状态、线程组等。
示例代码:
import java.util.concurrent.*;
import java.util.concurrent.atomic.*;
import java.util.concurrent.ThreadPoolExecutor.DiscardPolicy;
class SimpleThreadFactory implements ThreadFactory {
String name;
AtomicInteger threadNo = new AtomicInteger(0);
public SimpleThreadFactory (String name){
this.name = name;
}
public Thread newThread(Runnable r) {
String threadName = name+":"+threadNo.incrementAndGet();
System.out.println("threadName:"+threadName);
return new Thread(r,threadName );
}
public static void main(String args[]){
SimpleThreadFactory factory = new SimpleThreadFactory("Factory Thread");
ThreadPoolExecutor executor= new ThreadPoolExecutor(1,1,60,
TimeUnit.SECONDS,new ArrayBlockingQueue<Runnable>(1),new ThreadPoolExecutor.DiscardPolicy());
final ExecutorService executorService = Executors.newFixedThreadPool(5,factory);
for ( int i=0; i < 100; i++){
executorService.submit(new Runnable(){
public void run(){
System.out.println("Thread Name in Runnable:"+Thread.currentThread().getName());
}
});
}
executorService.shutdown();
}
}
输出:
java SimpleThreadFactory
thread no:1
thread no:2
Thread Name in Runnable:Factory Thread:1
Thread Name in Runnable:Factory Thread:2
thread no:3
thread no:4
Thread Name in Runnable:Factory Thread:3
Thread Name in Runnable:Factory Thread:4
thread no:5
Thread Name in Runnable:Factory Thread:5
等
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