/*
* 从运行结果看,当m1()方法被锁定后,m2()方法仍然可以执行。
* 而且b的值被改变。由此可以得出结论:
* sychronized 只是防止其定义的代码段被同时调用。
*
*/
public class Test implements Runnable{
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 {
Test t = new Test();
Thread th = new Thread(t);
th.start();
Thread.sleep(1000);//确保线程启动
t.m2();
}
}
/*
运行结果:
1000
b = 1000
*/
/*
* 从运行结果看,当m1()方法被锁定后,m2()方法仍然可以执行。
* 而且b的值被改变。由此可以得出结论:
* sychronized 只是防止其定义的代码段被同时调用。
* 将m2()锁定后,更改部分代码结果???
*
*/
public class Test implements Runnable{
int b = 100;
public synchronized void m1() throws Exception {
b = 1000;
Thread.sleep(5000);
System.out.println("b = " + b);
}
public synchronized void m2() throws Exception {
Thread.sleep(2500);
b = 2000;
}
public void run() {
try {
m1();
} catch(Exception e) {
e.printStackTrace();
}
}
public static void main(String[] args) throws Exception {
Test t = new Test();
Thread th = new Thread(t);
th.start();
Thread.sleep(1000);//确保线程启动
t.m2();
System.out.println(t.b);
}
}
/*
运行结果:
b = 1000
2000
*/