Thread类的基本用法（上）

一、线程创建方法（5种）

1.继承Thread类

class MyThread extends Thread {@Overridepublic void run() {System.out.println("MyThread is running");try {Thread.sleep(1000);} catch (InterruptedException e) {throw new RuntimeException(e);}}
}

这里中间运行的代码，需要抛出异常。

然后创建MyThread的实例，并执行

public class Demo1 {public static void main(String[] args) throws InterruptedException {Thread t = new MyThread();t.start();//t.run();while(true){System.out.println("hello world");Thread.sleep(1000);}}
}

2.实现Runnable接口

class MyRunnable implements Runnable {@Overridepublic void run() {while (true) {System.out.println("hello thread");try {Thread.sleep(1000);} catch (InterruptedException e) {throw new RuntimeException(e);}}}
}

然后创建Thread实例，将Runnable对象作为参数。

public class Demon2 {public static void main(String[] args) throws InterruptedException {Runnable runnable = new MyRunnable();Thread thread = new Thread(runnable);thread.start();while(true) {System.out.println("hello main");Thread.sleep(1000);}}
}

这里也可以写成

public class Demon2 {public static void main(String[] args) throws InterruptedException {
/*        Runnable runnable = new MyRunnable();Thread thread = new Thread(runnable);*/Thread thread = new Thread(new MyRunnable());thread.start();while(true) {System.out.println("hello main");Thread.sleep(1000);}}
}

后面的使用方法不变。

3.使用匿名内部类创建Thread子类对象

public class Demon2 {public static void main(String[] args) throws InterruptedException {Thread t = new Thread(){@Overridepublic void run() {while(true) {System.out.println("hello world");try {Thread.sleep(1000);} catch (InterruptedException e) {throw new RuntimeException(e);}}}};t.start();while(true) {System.out.println("hello my");Thread.sleep(1000);}}
}

实际上就是第一种方法的变形。

4.匿名内部类创建Runnable子类对象

public class Demon3 {public static void main(String[] args) throws InterruptedException {Runnable runnable = new Runnable() {@Overridepublic void run() {while(true) {System.out.println("hello world");try {Thread.sleep(1000);} catch (InterruptedException e) {throw new RuntimeException(e);}}}};Thread thread = new Thread(runnable);thread.start();while(true) {System.out.println("hello my");Thread.sleep(1000);}}
}

后面依旧需要创建Thread实例化，将Runnable作为对象参数传入。

5.使用lambda表达式创建子类

public class Demon4 {public static void main(String[] args) throws InterruptedException {Thread t  = new Thread(()->{while(true) {System.out.println("hello thread");try {Thread.sleep(1000);} catch (InterruptedException e) {throw new RuntimeException(e);}}});t.start();while(true) {System.out.println("hello my");Thread.sleep(1000);}}
}

这也是最简单最常用的方法。

二、线程中断

这里采用Thread中的interrupted方法

public class Demon10 {public static void main(String[] args) throws InterruptedException {Thread t = new Thread(()->{while(!Thread.currentThread().isInterrupted()){//System.out.println("t:"+Thread.currentThread().getName());System.out.println("hello thread");try {Thread.sleep(1000);} catch (InterruptedException e) {//throw new RuntimeException(e);break;}}System.out.println("t结束");});t.start();//System.out.println("main:"+Thread.currentThread().getName());Thread.sleep(3000);System.out.println("main尝试终止");t.interrupt();}
}

t.interrupt在调用后内部类中的while循环条件被打破，直接打印“t结束”。