Java Projects - Second Edition

ReentrantLock

ReentrantLock is the simplest implementation of the Lock interface in the JDK. There are two ways to create this type of lock—with and without a fairness policy. If the ReentrantLock(Boolean fair) constructor is called with true as an argument, then the lock will be assigned to the thread that is waiting for the lock the longest time in case there are many threads waiting. This will avoid a thread being made to wait for an inordinate amount of time and starving. On the other hand, handling the locks this way needs more administration from the ReentrantLock code and runs a bit slower. (Never be afraid of slow code until you have measured it.)