Java多线程――之一创建线程的四种方法

这篇文章主要介绍了Java创建线程方法，文中通过示例代码介绍的非常详细，对大家的学习或者工作具有一定的参考学习价值，需要的朋友们下面随着小编来一起学习学习吧

1.实现Runnable接口，重载run()，无返回值

 package thread; public class ThreadRunnable implements Runnable { public void run() { for (int i = 0; i <10; i++) { System.out.println(Thread.currentThread().getName() + ":" + i); } } } package thread; public class ThreadMain { public static void main(String[] args) throws Exception { ThreadRunnable threadRunnable1 = new ThreadRunnable(); ThreadRunnable threadRunnable2 = new ThreadRunnable(); ThreadRunnable threadRunnable3 = new ThreadRunnable(); ThreadRunnable threadRunnable4 = new ThreadRunnable(); Thread thread1 = new Thread(threadRunnable1); Thread thread2 = new Thread(threadRunnable2); Thread thread3 = new Thread(threadRunnable3); Thread thread4 = new Thread(threadRunnable4); thread1.start(); thread2.start(); thread3.start(); thread4.start(); } }

2.继承Thread类，复写run()

使用时通过调用Thread的start()（该方法是native），再调用创建线程的run()，不同线程的run方法里面的代码交替执行。

不足：由于java为单继承，若使用线程类已经有个父类，则不能使用该方式创建线程。

 public class ThreadEx extends Thread { public void run() { for (int i = 0; i <10; i++) { System.out.println(Thread.currentThread() + ":" + i); } } } public class ThreadMain { public static void main(String[] args) { ThreadEx threadEx = new ThreadEx(); threadEx.start(); } }

3.实现Callable接口，通过FutureTask/Future来创建有返回值的Thread线程，通过Executor执行

补充：与实现Runnable接口类似，都是实现接口，不同的是该方式有返回值，可以获得异步执行的结果。

延伸：FutureTask是类，Future是接口。

 package thread; import java.util.concurrent.*; public class ThreadCallable { public static void main(String[] args) throws Exception { FutureTask futureTask = new FutureTask(new Callable() { public Integer call() throws Exception { for (int i = 0; i <10; i++) { System.out.println(Thread.currentThread().getName() + ":" + i); } return 1; } }); Executor executor = Executors.newFixedThreadPool(1); ((ExecutorService) executor).submit(futureTask); //获得线程执行状态 System.out.println(Thread.currentThread().getName() + ":" + futureTask.get()); } }

4.使用Executors创建ExecutorService，入参Callable或Future

补充：适用于线程池和并发

 package thread; import java.util.concurrent.Callable; import java.util.concurrent.Executors; import java.util.concurrent.ThreadFactory; import static java.lang.Thread.sleep; public class ThreadExecutors { private final String threadName; public ThreadExecutors(String threadName) { this.threadName = threadName; } private ThreadFactory createThread() { ThreadFactory tf = new ThreadFactory() { public Thread newThread(Runnable r) { Thread thread = new Thread(); thread.setName(threadName); thread.setDaemon(true); try { sleep(1000); } catch (InterruptedException e) { e.printStackTrace(); } return thread; } }; return tf; } public Object runCallable(Callable callable) { return Executors.newSingleThreadExecutor(createThread()).submit(callable); } public Object runFunture(Runnable runnable) { return Executors.newSingleThreadExecutor(createThread()).submit(runnable); } } package thread; import java.util.concurrent.*; public class ThreadMain { public static void main(String[] args) throws Exception { ThreadExecutors threadExecutors = new ThreadExecutors("callableThread"); threadExecutors.runCallable(new Callable() { public String call() throws Exception { return "success"; } }); threadExecutors.runFunture(new Runnable() { public void run() { System.out.println("execute runnable thread."); } }); } }

5 Runnable接口和Callable接口区别