join与中断线程（2）
1、join
join()方法：加入线程让调用的线程先执行指定时间或者是指向完毕
异常：InterruptedException-如果任何线程中断当前线程。当抛出异常时，当前线程的中断状态被清除package com.huanghe;
/**
* @Author: River
* @Date:Created in 10:27 2018/5/28
* @Description: join()方法：加入线程让调用的线程先执行指定时间或者是指向完毕
*/
public class ThreadDemo2 {
public static void main(String[] args) {
MyRunable2 mr2 = new MyRunable2();
Thread t = new Thread(mr2);
t.start();
for (int i = 0; i <20 ; i++) {
System.out.println(Thread.currentThread().getName()+"--"+i);
try {
Thread.sleep(500);
} catch (InterruptedException e) {
e.printStackTrace();
}
if (i == 10) {
try {
t.join();//让t线程执行完毕
}catch (InterruptedException e){
e.printStackTrace();
}
}
}
}
}
class MyRunable2 implements Runnable{
@Override
public void run() {
for (int i = 0; i <20 ; i++) {
System.out.println(Thread.currentThread().getName()+"--"+i);
try {
Thread.sleep(500);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
执行的结果如下：
main--0
Thread-0--0
main--1
Thread-0--1
main--2
Thread-0--2
main--3
Thread-0--3
Thread-0--4
main--4
Thread-0--5
main--5
Thread-0--6
main--6
Thread-0--7
main--7
main--8
Thread-0--8
Thread-0--9
main--9
main--10
Thread-0--10
Thread-0--11
Thread-0--12
Thread-0--13
Thread-0--14
Thread-0--15
Thread-0--16
Thread-0--17
Thread-0--18
Thread-0--19
main--11
main--12
main--13
main--14
main--15
main--16
main--17
main--18
main--19
2、中断
public void interrupt():
//中断这个线程
//除非当前线程中断自身，这是始终允许的public static boolean interrupted()
//测试当前线程是否中断。该方法可以清除中断状态。换句话说，如果这个方法被连续的调用两次，那么第二个调用将返回false(除非当前线程再次中断，在第一个调用已经清除其中的中断状态之后，在第二个调用之前已经检查过)package com.huanghe;
/**
* @Author: River
* @Date:Created in 10:27 2018/5/28
* @Description: join()方法：加入线程让调用的线程先执行指定时间或者是指向完毕
*/
public class ThreadDemo2 {
public static void main(String[] args) {
MyRunable2 mr2 = new MyRunable2();
Thread t = new Thread(mr2);
t.start();
for (int i = 0; i <20 ; i++) {
System.out.println(Thread.currentThread().getName()+"--"+i);
try {
Thread.sleep(500);
} catch (InterruptedException e) {
e.printStackTrace();
}
if (i == 10) {
// try {
// t.join();//让t线程执行完毕
// }catch (InterruptedException e){
// e.printStackTrace();
// }
t.interrupt();//1、中断线程,中断标记
}
}
}
}
class MyRunable2 implements Runnable{
@Override
public void run() {
for (int i = 0; i <20 ; i++) {
if (Thread.interrupted()){//4）测试中断状态，此方法会把中断标记清除
break;
}
System.out.println(Thread.currentThread().getName()+"--"+i);
try {
Thread.sleep(500);
} catch (InterruptedException e) {
e.printStackTrace(); //2、因为在sleep中会抛出中断异常，并且异常会被清除
t.interrupt();//3、中断标记需要再次的被打上
}
}
}
}
//执行的结果
main--0
Thread-0--0
main--1
java.lang.InterruptedException: sleep interrupted
Thread-0--1
at java.lang.Thread.sleep(Native Method)
at com.huanghe.MyRunable2.run(ThreadDemo2.java:42)
at java.lang.Thread.run(Thread.java:745)
java.lang.InterruptedException: sleep interrupted
main--2
Thread-0--2
at java.lang.Thread.sleep(Native Method)
at com.huanghe.MyRunable2.run(ThreadDemo2.java:42)
at java.lang.Thread.run(Thread.java:745)
main--3
java.lang.InterruptedException: sleep interrupted
Thread-0--3
at java.lang.Thread.sleep(Native Method)
Thread-0--4
at com.huanghe.MyRunable2.run(ThreadDemo2.java:42)
at java.lang.Thread.run(Thread.java:745)
main--4
java.lang.InterruptedException: sleep interrupted
Thread-0--5
at java.lang.Thread.sleep(Native Method)
Thread-0--6
at com.huanghe.MyRunable2.run(ThreadDemo2.java:42)
at java.lang.Thread.run(Thread.java:745)
java.lang.InterruptedException: sleep interrupted
at java.lang.Thread.sleep(Native Method)
at com.huanghe.MyRunable2.run(ThreadDemo2.java:42)
at java.lang.Thread.run(Thread.java:745)
Thread-0--7
main--5
java.lang.InterruptedException: sleep interrupted
Thread-0--8
at java.lang.Thread.sleep(Native Method)
main--6
at com.huanghe.MyRunable2.run(ThreadDemo2.java:42)
Thread-0--9
at java.lang.Thread.run(Thread.java:745)
java.lang.InterruptedException: sleep interrupted
main--7
at java.lang.Thread.sleep(Native Method)
Thread-0--10
at com.huanghe.MyRunable2.run(ThreadDemo2.java:42)
Thread-0--11
at java.lang.Thread.run(Thread.java:745)
java.lang.InterruptedException: sleep interrupted
main--8
at java.lang.Thread.sleep(Native Method)
Thread-0--12
at com.huanghe.MyRunable2.run(ThreadDemo2.java:42)
at java.lang.Thread.run(Thread.java:745)
java.lang.InterruptedException: sleep interrupted
Thread-0--13
at java.lang.Thread.sleep(Native Method)
main--9
at com.huanghe.MyRunable2.run(ThreadDemo2.java:42)
Thread-0--14
at java.lang.Thread.run(Thread.java:745)
java.lang.InterruptedException: sleep interrupted
at java.lang.Thread.sleep(Native Method)
at com.huanghe.MyRunable2.run(ThreadDemo2.java:42)
at java.lang.Thread.run(Thread.java:745)
Thread-0--15
main--10
Thread-0--16
java.lang.InterruptedException: sleep interrupted
at java.lang.Thread.sleep(Native Method)
at com.huanghe.MyRunable2.run(ThreadDemo2.java:42)
at java.lang.Thread.run(Thread.java:745)
main--11
Thread-0--17
main--12
java.lang.InterruptedException: sleep interrupted
Thread-0--18
at java.lang.Thread.sleep(Native Method)
Thread-0--19
at com.huanghe.MyRunable2.run(ThreadDemo2.java:42)
at java.lang.Thread.run(Thread.java:745)
main--13
java.lang.InterruptedException: sleep interrupted
at java.lang.Thread.sleep(Native Method)
at com.huanghe.MyRunable2.run(ThreadDemo2.java:42)
at java.lang.Thread.run(Thread.java:745)
main--14
main--15
main--16
main--17
main--18
main--19
从执行的结果中可以看出，程序并没有停止执行，但是抛出了异常，这个异常是Runable里面的sleep抛出的异常，t.interrup();只是做了一个中断标记，t是不是真的需要中断进行，需要线程自己进行决定；
所以如果需要完成一个正常的中断，需要上面的四步才可以顺序的完成
3、自定义标记中断线程
由于上面的中断过程很麻烦，所以在做中断线程的时候使用的是自定义中断线程
package com.huanghe;
/**
* @Author: River
* @Date:Created in 10:27 2018/5/28
* @Description: join()方法：加入线程让调用的线程先执行指定时间或者是指向完毕
* (1):使用Interrupt方法中断线程，设置一个中断标记
* (2):自定义中断标记
*/
public class ThreadDemo2 {
public static void main(String[] args) {
MyRunable2 mr2 = new MyRunable2();
Thread t = new Thread(mr2);
// t.start();
MyRunable3 mr3 = new MyRunable3();
Thread t2 = new Thread(mr3);
t2.start();
for (int i = 0; i <20 ; i++) {
System.out.println(Thread.currentThread().getName()+"--"+i);
try {
Thread.sleep(500);
} catch (InterruptedException e) {
e.printStackTrace();
}
if (i == 10) {
// try {
// t.join();//让t线程执行完毕
// }catch (InterruptedException e){
// e.printStackTrace();
// }
// t.interrupt();//中断线程,中断标记
mr3.flag=false;//自定义中断异常
}
}
}
}
class MyRunable2 implements Runnable{
@Override
public void run() {
for (int i = 0; i <20 ; i++) {
if (Thread.interrupted()){//测试中断状态，此方法会把中断标记清除
break;
}
System.out.println(Thread.currentThread().getName()+"--"+i);
try {
Thread.sleep(500);
} catch (InterruptedException e) {
e.printStackTrace();
Thread.currentThread().interrupt();
}
}
}
}
class MyRunable3 implements Runnable{
public boolean flag=true;
public MyRunable3(){
flag = true;
}
@Override
public void run() {
int i = 0;
while (flag) {
System.out.println(Thread.currentThread().getName() + "====" + (i++));
try {
Thread.sleep(300);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}