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objects and threads

sylvia greene
Ranch Hand

Joined: Jun 23, 2004
Posts: 40

A thread can't invoke a wait or notify method on an object unless it owns that objects lock

I can't the concept of object here.

What is a thread and what is a object here?

Isn't "b" both an object and thread? what's object being referred to here.
Barry Gaunt
Ranch Hand

Joined: Aug 03, 2002
Posts: 7729
Yes, in this case, b is an object and a Thread (Thread is derived from object). The wait() and notify() are being called on the shared object b The b in the main method refers to the same object as this in the run method of object b.

Ask a Meaningful Question and HowToAskQuestionsOnJavaRanch
Getting someone to think and try something out is much more useful than just telling them the answer.
It is sorta covered in the JavaRanch Style Guide.
subject: objects and threads