muyou -- 线程

package webDemo;public class SyncTest {static class PrintMachine{// 线程不安全的private StringBuilder sb = new StringBuilder();public synchronized void print(String content) {sb.append(Thread.currentThread().getName()).append(":").append(content).append("\r\n"); }public synchronized void show() {System.out.println(sb.toString());}} public static void main(String[] args) {PrintMachine mc = new PrintMachine();// 用户1 Runnable run1 = new Runnable() {@Overridepublic void run() {mc.print("user1");}};// 用户2Runnable run2 = new Runnable() {@Overridepublic void run() {mc.print("user2");}};new Thread(run1,"线程1的名字").start();new Thread(run2,"线程2的名字").start();try {Thread.sleep(1000);} catch (InterruptedException e) {e.printStackTrace();}mc.show();}}