views:

629

answers:

2

I was wondering if

synchronize (lock) {
    ... 
}

Where lock is an instance of java.util.concurrent.locks.Lock, treats lock like any other object or as the try-finally idiom i.e.

 lock.lock(); 
 try {
     ... 
 } finally { 
    lock.unlock();
 }
+12  A: 

Lock documentation:

Note that Lock instances are just normal objects and can themselves be used as the target in a synchronized statement. Acquiring the monitor lock of a Lock instance has no specified relationship with invoking any of the lock() methods of that instance. It is recommended that to avoid confusion you never use Lock instances in this way, except within their own implementation.

So basically, it's treated as any other object. And, don't do that.

Matthew Flaschen
why "Don't do that"?
hhafez
@hhafez: "Don't do that" because the documentation says "It is recommended that to avoid confusion you never use Lock instances in this way, except within their own implementation."
Grant Wagner
FindBugs will find this bug.
Tom Hawtin - tackline
+2  A: 

It will treat the lock just like any other object.

AgileJon