i want to learn concurrnecy utilities. is the concurrency utilities is replace java multithreaing old concept or if not why Concurrency Utilities is used and where is used???
and which is the ood tutorial and book for Concurrency Utilities???
Not it is not a replacement, but rather an extension of well known mechanisms such as wait/notify, intrinstic locks and so on.
These utilities provide high-level abstractions (e.g. semaphores, latches, barriers) on the one hand and completely new concepts (e.g. Locks, Atomic objects) on the other hand.
It makes no sense to explain you details of these packages because if you want to learn them you would do that on your own because there is Google
If you want to go deep into multithreading then you absolutely have to read the book "Java Concurrency in Practice" - there you will find answers on all your questions.