Because it doesn’t matter whether I pass String’s instance, Some random class’s instance to the synchronized block as the synchronized block works perfectly irrespective of the parameter being passed to the block. The purpose of the parameter is twofold: It makes it possible to synchronize other blocks on the same object, so that if you … Read more
A synchronized method uses the method receiver as a lock (i.e. this for non static methods, and the enclosing class for static methods). Synchronized blocks uses the expression as a lock. So the following two methods are equivalent from locking prospective: synchronized void mymethod() { … } void mymethod() { synchronized (this) { … } … Read more
Personally I almost never lock on “this”. I usually lock on a privately held reference which I know that no other code is going to lock on. If you lock on “this” then any other code which knows about your object might choose to lock on it. While it’s unlikely to happen, it certainly could … Read more
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 … Read more