In [JavaDoc of PhantomReference](http://docs.oracle.com/javase/6/docs/api/java/lang/ref/PhantomReference.html), I read:

> In order to ensure that a reclaimable object remains so, the referent of a phantom reference may not be retrieved: The get method of a phantom reference always returns null.

So I guess `get` should be overridden here to return `null`