synchronized keyword

[Vidyavathi saravanan]

There is a question in one of Marc exam. Sorry I dont remember the exact wordings. But the essence is -
Is 'synchronized' keyword to be used only within classes that extend Thread?

[Corey McGlone]

No. Synchronized should be used anywhere that you do not want two or more threads accessing at the same time. That could easily be within a class that does not extend Thread.
[ November 01, 2004: Message edited by: Corey McGlone ]

[marc weber]

Every object has a lock, and every class has a lock.

Synchronized code requires that an executing thread acquire the lock before it can invoke the code.

So in other words, synchronized code does not need to be in a Thread object, but it does regulate how different threads are able to invoke that code.

Does that make sense?