Question

Hello im trying to simulate a worker thread in Android for testing. The activity has a button that calls notify() over the worker thread, and I want it go to sleep after 10 iterations of the bucle.

这是我的法典和错误的 st。我如何解决这一问题? 增编

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);


    t= new Thread(){
        public void run(){
            int i=0;
            while(true){


                if (i%10==9){
                    //Simulated end of data until notified again
                    try {
                        this.wait();
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                }
            Log.d("Test",""+i);
            SystemClock.sleep(1000);
            } 
        }
    };
    t.start();


    findViewById(R.id.button1).setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            t.notify();

        }
    });
}





08-06 05:39:45.320: ERROR/AndroidRuntime(4480): FATAL EXCEPTION: main
08-06 05:39:45.320: ERROR/AndroidRuntime(4480): java.lang.IllegalMonitorStateException: object not locked by thread before notify()
08-06 05:39:45.320: ERROR/AndroidRuntime(4480):     at java.lang.Object.notify(Native Method)
08-06 05:39:45.320: ERROR/AndroidRuntime(4480):     at com.example.memorycrash.MemoryCrashTestActivity$2.onClick(MemoryCrashTestActivity.java:51)
08-06 05:39:45.320: ERROR/AndroidRuntime(4480):     at android.view.View.performClick(View.java:2538)
08-06 05:39:45.320: ERROR/AndroidRuntime(4480):     at android.view.View$PerformClick.run(View.java:9152)
08-06 05:39:45.320: ERROR/AndroidRuntime(4480):     at android.os.Handler.handleCallback(Handler.java:587)
08-06 05:39:45.320: ERROR/AndroidRuntime(4480):     at android.os.Handler.dispatchMessage(Handler.java:92)
08-06 05:39:45.320: ERROR/AndroidRuntime(4480):     at android.os.Looper.loop(Looper.java:130)
08-06 05:39:45.320: ERROR/AndroidRuntime(4480):     at android.app.ActivityThread.main(ActivityThread.java:3687)
08-06 05:39:45.320: ERROR/AndroidRuntime(4480):     at java.lang.reflect.Method.invokeNative(Native Method)
08-06 05:39:45.320: ERROR/AndroidRuntime(4480):     at java.lang.reflect.Method.invoke(Method.java:507)
08-06 05:39:45.320: ERROR/AndroidRuntime(4480):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:842)
08-06 05:39:45.320: ERROR/AndroidRuntime(4480):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:600)
08-06 05:39:45.320: ERROR/AndroidRuntime(4480):     at dalvik.system.NativeStart.main(Native Method)

Answer 1

So here is your solution. Answer was already there on StackOverflow.

为了要求等待、通知或通知所有物体,你必须首先拥有对你希望使用的物体的监测,因此,在你可以操作的情形下,你需要做些什么:

Runnable runnable = new Runnable() {
    public void run() {
      // wait(); This call wouldn t work
      syncronized (this) {
        wait();  // This call will work
      }
    }
};

To notify that runnable you would also have to have the monitor

// runnable.notifyAll(); this call will not work
syncronized (runnable) {
    runnable.notifyAll(); // this call will work
}

友情链接