關於Java多線程中的join方法，我自己的理解就是會強行進入使用join方法的線程，其他線程等待該線程完全執行完後才會進來。
先上代碼
新建一個Thread,代碼如下:
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();
}
}
之後新建測試類,代碼如下:
package com.thread.test;
/*
* 0-50執行的是主線程,50-100執行的是A線程,並且將A線程完全執行完後才繼續執行主線程
*/
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("主線程"+"["+i+"]");
}
}
}
下面是Java Platform SE8 API中對Thread中Join方法的解釋:
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.碼
新建一個Thread,代碼如下:
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();
}
}
之後新建測試類,代碼如下:
package com.thread.test;
/*
* 0-50執行的是主線程,50-100執行的是A線程,並且將A線程完全執行完後才繼續執行主線程
*/
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("主線程"+"["+i+"]");
}
}
}
下面是Java Platform SE8 API中對Thread中Join方法的解釋:
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.