/** * * @version: 1.1.0 * @Description: 多线程 * @author: wsq * @date: 2020年6月8日下午2:25:33 */ public class MyThread extends Thread{ @Override public void run() { System.out.println("This is the first thread!"); } public static void main(String[] args) { MyThread mt = new MyThread(); mt.start(); } }
public class MultithreadingTest { public static void main(String[] args) { new Thread(() -> System.out.println("This is the first thread!")).start(); } }
或者
public class MyThreadImpl implements Runnable{ private int count = 5; @Override public void run() { // TODO Auto-generated method stub count--; System.out.println("Thread"+Thread.currentThread().getName()+"count:"+count); } }
/** * * @version: 1.1.0 * @Description: 测试类 * @author: wsq * @date: 2020年6月8日下午9:27:02 */ public class Test { public static void main(String[] args) { MyThreadImpl myThreadImpl = new MyThreadImpl(); Thread A = new Thread(myThreadImpl,"A"); Thread B = new Thread(myThreadImpl,"B"); Thread C = new Thread(myThreadImpl,"C"); Thread D = new Thread(myThreadImpl,"D"); Thread E = new Thread(myThreadImpl,"E"); A.start(); B.start(); C.start(); D.start(); E.start(); } }
打印结果为:
ThreadBcount:3
ThreadCcount:2
ThreadAcount:3
ThreadDcount:1
ThreadEcount:0
B和A共用一个线程,存在线程安全问题
改成:
public class MyThreadImpl implements Runnable{ private int count = 5; @Override // 使用同步解决线程安全问题 synchronized public void run() { // TODO Auto-generated method stub count--; System.out.println("Thread"+Thread.currentThread().getName()+"count:"+count); } }
原文:https://www.cnblogs.com/mcjhcnblogs/p/13068664.html