第九章 Java多线程机制 05_线程同步_4

鱼欲遇雨：每日都学习一点，持之以恒，天道酬勤！不能用电脑时，提前补上！（2012.9.3）

java的一道面试题

public class TT  {private int b = 100;public synchronized void m1() throws Exception {b = 1000;Thread.sleep(5000);System.out.println("b = " + b);}public void m2() {System.out.println(b);}}

问，当方法m1()锁定的时候，可不可以调用m2()?输出b的值

代码示例：

// TT.javapublic class TT implements Runnable {private int b = 100;public synchronized void m1() throws Exception {b = 1000;Thread.sleep(5000);System.out.println("b = " + b);}public void m2() {System.out.println(b);}public void run() {try{m1();}catch (Exception e){e.printStackTrace();}}public static void main(String args[]) throws Exception {TT tt = new TT();Thread t = new Thread(tt);t.start();Thread.sleep(1000);tt.m2();}}

答案是可以的！