问一个synchronized 的问题
假设一个Class如下
public Class A
{
...
public synchronized void method1 {
...
}
public synchronized void method2 {
...
}
}
A obj = new A();
如果有1个线程1正在调用 obj 的method1, 是不是另一个线程2就连obj的method2都不能调用？
谢谢
[解决办法]
站在上面的同志们的肩上写了个DEMO代码，刚好帮自己复习一下，希望对你有用。
package cn.luochengor.csdn;import java.util.concurrent.ExecutorService;import java.util.concurrent.Executors;import java.util.concurrent.TimeUnit;/** * synchronized * * @Author luochengor * @Date Nov 25, 2011 * @Email luochengor@foxmail.com */public class Synchronized { /** * @param args */ public static void main(String[] args) { ExecutorService exec = Executors.newCachedThreadPool(); D d = new D(); exec.execute(new ThreadA(d)); exec.execute(new ThreadB(d)); }}class D { public synchronized void method1() { try { System.out.println("D.method1()"); System.out.println("method-1 start to sleep."); TimeUnit.SECONDS.sleep(1); System.out.println("method-1 wake up."); } catch (InterruptedException e) { System.out.println("method-1 is interrupted."); } } public synchronized void method2() { try { System.out.println("D.method2()"); System.out.println("method-2 start to sleep."); TimeUnit.SECONDS.sleep(3); System.out.println("method-2 wake up."); } catch (InterruptedException e) { System.out.println("method-2 is interrupted."); } } public void unSynchronized() { System.out.println("This is unSynchronized method."); }}class ThreadA implements Runnable { private D d; public ThreadA(D d) { this.d = d; } @Override public void run() { while (!Thread.interrupted()) { try { System.out.println("ThreadA.run start doing method1()."); d.unSynchronized(); d.method1(); TimeUnit.SECONDS.sleep(1); } catch (InterruptedException e) { System.out.println("ThreadA.run is interrupted."); } } }}class ThreadB implements Runnable { private D d; public ThreadB(D d) { this.d = d; } @Override public void run() { while (!Thread.interrupted()) { try { System.out.println("ThreadB.run start doing method2()."); d.unSynchronized(); d.method2(); TimeUnit.SECONDS.sleep(1); } catch (InterruptedException e) { System.out.println("ThreadB.run is interrupted."); } } }}