deadlock : Java Glossary

by Roedy Green ©1996-2008 Canadian Mind Products
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deadlock

When two threads interfere in such a way that neither can continue. Sometimes called deadly embrace or Mexican standoff. There is absolutely nothing you can do with a deadlocked thread. You cannot stop it, you cannot interrupt it, you cannot tell it to stop trying to get a lock, and you also cannot tell it to let go of the locks that it owns. This is one of the criticism in Doug Lea’s book about the primitive monitor-based locking mechanisms. Once you try to get a lock, you will forever try and never give up. The concurrency handling mechanisms of Doug’s book are now in the java.util.concurrent package of JDK 1.5.

recommend book⇒Concurrent Programming in Java: Design Principles and Patterns, Second Edition

paperback

ISBN13:

978-0-201-69581-6

ISBN10:

0-201-69581-2

publisher:

Addison-Wesley

published:

1996-11

by:

Doug Lea

339 pages. You can read it on-line. This is the book on Threads and concurrent programming.

	amazon.ca	amazon.com
	chapters.indigo.ca	powells.com
	amazon.fr	barnesandnoble.com
	amazon.de	amazon.co.uk

The classic way it happens is by thread 1 locking object a then trying to get a lock on object b, while thread 1 gets a lock on object b and tries to get a lock on object a. The simplest way to avoid this is to always acquire locks in canonical order.

detecting deadlock
thread
thread safe code

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