In java, return value within synchronized block seems like bad style. Does it really matter?

Question

I have a Collections.synchronizedList of WeakReference, _components;

I wrote something like the following, expecting the complier to complain:

public boolean addComponent2(Component e) {     synchronized (_components) {         return _components.add(new WeakReference<Component>(e));     }         } 

But the compiler is perfectly satisfied. Note that List.add() returns TRUE. So ok, any exit from a synchronized block releases the lock, but doesn't this LOOK strange? It's kind of like a "hole" in the block, similar to using return in a loop.

Would you be happy maintaining code like this?

Answer 1

It's absolutely fine - as is returning from a loop, or from a try block which has an appropriate finally block. You just need to be aware of the semantics, at which point it makes perfect sense.

It's certainly simpler code than introducing a local variable for the sake of it:

// Ick - method body is now more complicated, with no benefit public boolean addComponent2(Component e) {     boolean ret;     synchronized (_components) {         ret = _components.add(new WeakReference<Component>(e));     }     return ret; }