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ReentrantReadWriteLock readLock()

 
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i don`t understand behavior of tryLock()


Acquires the read lock only if the write lock is not held by another thread at the time of invocation.


i start thread`s that will get read lock, pause it for main thread can get write lock.
than after getting write lock i make pause main threads for threads have chance get it read lock - and they did it.
when i test same with lock() - it work as i expected, but this time i see that tryLock get lock even if i had already acquired write lock.
What is problem???
 
author and jackaroo
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May I suggest one little change to your code at line 22 from your pasted code (might be a different line number in your IDE, as you don't have the "include" statement in your code above):



What does that give you as output? Does that make more sense of what is happening?
 
Sergej Smoljanov
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yes. My firs understand was that if not get read lock - it will block. Now understand that if not - just return false. thanks.
 
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Sergej you can read the API Docs for such confusions. The API docs for tryLock method states:

tryLock Java Docs wrote:Acquires the lock only if it is free at the time of invocation.
Acquires the lock if it is available and returns immediately with the value true. If the lock is not available then this method will return immediately with the value false.

 
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