JAVA multithreading learning (2) ---- JAVA realizes multithreading

The previous article is all about the basic understanding of multithreading. After understanding, continue to return to JAVA to realize multithreading

JAVA multi-threaded class: Thread
first look at thread.



As you can see from the above, there are two ways to create multi-threads:

• Inherit Thread, rewrite the run method
• Implement Runnable, rewrite the ruN method

Inherit Thread

public class Main extends Thread {
    
    
    @Override
    public void run() {
    
    
        for (int i = 0; i < 200; i++) {
    
    
            System.out.println("多多多多敲代码");
        }
    }
    public static void main(String[] args) {
    
    
        Main test = new Main();
        test.run();
        for (int i = 0; i < 2000; i++) {
    
    
            System.out.println("i = " + i);
        }
    }
}

//输出结果，先输出完200多多多多敲代码，再到2000次i
部分展示：
多多多多敲代码
多多多多敲代码
多多多多敲代码
多多多多敲代码
i = 0
i = 1
i = 2
i = 3
i = 4

However, if .start is executed alternately, the effect of more cycles is obvious

public class Main extends Thread {
    
    
    @Override
    public void run() {
    
    
        for (int i = 0; i < 200; i++) {
    
    
            System.out.println("多多多多敲代码");
        }
    }
    public static void main(String[] args) {
    
    
        Main test = new Main();
        test.start();
        for (int i = 0; i < 2000; i++) {
    
    
            System.out.println("i = " + i);
        }
    }
}
//输出结果，交替执行
部分展示：
多多多多敲代码
多多多多敲代码
多多多多敲代码
i = 1
多多多多敲代码
多多多多敲代码
多多多多敲代码

Implement the Runnable interface

public class TestThread implements Runnable{
    
    
    @Override
    public void run() {
    
    
        for (int i = 0; i < 20; i++) {
    
    
            System.out.println("多多多多敲代码");
        }
    }

    public static void main(String[] args) {
    
    
        TestThread testThread = new TestThread();
        //通过线程对象来开启我们的线程，代理
        //new Thread(testThread).run();
		new Thread(testThread).start();
        for (int i = 0; i < 2000; i++) {
    
    
            System.out.println("i = " + i);
        }
    }
}

运行结果与上面一致，不做过多的描述

Therefore, the following figure can be obtained

What is the difference between the above two implementations?

1. Inherit the Thread class
   ①Subclass inherit the Thread class to have multi-threading ability
   ②Start method: subclass.start() ③Not
   recommended: Single inheritance limitations

2. Realize Runnable interface
   ①Realize Runnable with multi-threading ability
   ②Start method: pass in the target object + Thread object.start() ③Recommendation
   : flexible and convenient, avoiding the limitation of single inheritance

Most of the content of the article is personally organized, refer to the article cited by java3y