新建一个Thread,代码如下:
package com.thread.test;
public class MyThread extends Thread {
private String name;
public MyThread(String name) {
this.name = name;
}
@Override
public void run() {
for (int i = 0; i < 100; i++) {
System.out.println(name+"["+i+"]");
}
super.run();
}
}
之后新建测试类,代码如下:
package com.thread.test;
/*
* 0-50执行的是主线程,50-100执行的是A线程,并且将A线程完全执行完后才继续执行主线程
*/
public class ThreadDemo{
public static void main(String[] args) {
MyThread t = new MyThread("A");
t.start();
for (int i = 0; i < 100; i++) {
if (i>50) {
try {
t.join();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
System.out.println("主线程"+"["+i+"]");
}
}
}
下面是Java Platform SE8 API中对Thread中Join方法的解释:
public final void join(long millis)
throws InterruptedExceptionWaits at most millis milliseconds for this thread to die. A timeout of 0 means to wait forever.
This implementation uses a loop of this.wait calls conditioned on this.isAlive. As a thread terminates the this.notifyAll method is invoked. It is recommended that applications not use wait, notify, or notifyAll on Thread instances.
Parameters:
millis - the time to wait in milliseconds
Throws:
IllegalArgumentException - if the value of millis is negative
InterruptedException - if any thread has interrupted the current thread. The interrupted status of the current thread is cleared when this exception is thrown.
先上代码
新建一个Thread,代码如下:
package com.thread.test;
public class MyThread extends Thread {
private String name;
public MyThread(String name) {
this.name = name;
}
@Override
public void run() {
for (int i = 0; i < 100; i++) {
System.out.println(name+"["+i+"]");
}
super.run();
}
}
之后新建测试类,代码如下:
package com.thread.test;
/*
* 0-50执行的是主线程,50-100执行的是A线程,并且将A线程完全执行完后才继续执行主线程
*/
public class ThreadDemo{
public static void main(String[] args) {
MyThread t = new MyThread("A");
t.start();
for (int i = 0; i < 100; i++) {
if (i>50) {
try {
t.join();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
System.out.println("主线程"+"["+i+"]");
}
}
}
下面是Java Platform SE8 API中对Thread中Join方法的解释:
public final void join(long millis)
throws InterruptedExceptionWaits at most millis milliseconds for this thread to die. A timeout of 0 means to wait forever.
This implementation uses a loop of this.wait calls conditioned on this.isAlive. As a thread terminates the this.notifyAll method is invoked. It is recommended that applications not use wait, notify, or notifyAll on Thread instances.
Parameters:
millis - the time to wait in milliseconds
Throws:
IllegalArgumentException - if the value of millis is negative
InterruptedException - if any thread has interrupted the current thread. The interrupted status of the current thread is cleared when this exception is thrown.
我自己的理解就是会强行进入使用join方法的线程，其他线程等待该线程完全执行完后才会进来。