Spring bean threadsafety

Recently working on multi-thread safety issues, and read a interesting article regarding spring bean and thread safe. http://tarunsapra.wordpress.com/2011/08/21/spring-singleton-request-session-beans-and-thread-safety/ Please be aware one more thing, spring singleton is not a true singleton, is one instance per application context. So it is possible there are multiple instances inside JVM.

Four questions for every solution

1. What is the problem 2. What is the solution 3. Solution Matrix for Advantage and disadvantage. 4. What is the best solution http://www.dzone.com/links/r/is_programming_the_art_of_making_the_right_decisi.html

Java deadLock

Below it is the link of a blog regarding java dead Lock, it is very useful. http://www.captaindebug.com/p/blogs-on-investigating-deadlocks.html