Question: I have a Spotlight source in OpenGL, pointing towards a texture mapped sphere. 

I rotate the lightsource with the sphere, such that if I rotate the sphere to the 'non-light' side, that side should be dark. 

The odd part is, the spotlight seems to be shining through my sphere (it's a solid, no gaps between triangles. The light seems to be 'leaking' through to the other side. 

Any thoughts on why this is happening?

Screenshots:

[Front view, low light to emphasize the problem](http://www.logisticchaos.com/front.png)

[Back view, notice the round area that is 'shining through'](http://www.logisticchaos.com/back.png)

Answer: 
If you are using `java.util.concurrent.locks.ReentrantLock` then a subclass can call `getOwner`.

Alternatively you can use JMX. Iterate through threads to find the `java.lang.management.ThreadInfo` with appropriate `getLockedMonitors()` or `getLockedSynchronizers()`.
I believe it is not possible to do that. However you can do something similar with some extra coding:

```
public void myFunction() {
  System.out.println("" + Thread.currentThread() + " entering sync @ myFunction");
  synchronized(this) {
    System.out.println("" + Thread.currentThread() + " entered sync @ myFunction");

    ...

    System.out.println("" + Thread.currentThread() + " leaving sync @ myFunction");
  }
  System.out.println("" + Thread.currentThread() + " left sync @ myFunction");
}

```