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SCJD Book Page 154

Keith Nagle
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Joined: May 06, 2008
Posts: 65
Hi guys, quick question about the reserveDVD and releaseDVD methods on pages 154 & 155 of the
SCJD book (Monkhouse & Camerlengo).

Can someone please explain the reserveDVD and releaseDVD methods to me in Layman's terms?

I've tried to get my head around these 2 methods but can't seem to.

Mainly the questions I have about the reserveDVD method are

If a thread acquires the lock, what is the point in it having to invoke



If a thread get's the lock, will this "if" statement wait immediately return true? Or, will 5 seconds always and then true will be returned.

Also, above all, if a thread can't obtain the lock by calling "lock.lock()" and blocks, how does the "if(!lockReleased.await(timeLeftMSec, TimeUnit....)" statement help us?
The reason I ask, is that if the lock is released and our blocking thread picks up the lock and enters the running state, the "if(!lockReleased.await(...))" will never
return false.

Any help greatly received,
Regards

SCJP 5.0
 
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subject: SCJD Book Page 154
 
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