synchronized block vs ReentantLock performance

Java synchronized block vs ReentantLock performance

Result summary

Result (100000 run, 10 thread)

	Time [ms]
Without synchronization	282
Synchronized block	7453
ReentrantLock lock	516
ReentantReadWriteLock read lock	344
ReentantReadWriteLock write lock	516

Conclusion: The java new locking mechanism is significant faster than old synchronized block strategy, in the result you can see the read/write lock benefits, because it's not block the other threads.

ps: In the test, we only get one item from HashMap, and after that we call Thread.yield (emulate the running thread changed before unlock the resource).