Releases a permit, returning it to the semaphore.
Releases a permit, increasing the number of available permits by one. If any threads are trying to acquire a permit, then one is selected and given the permit that was just released. That thread is (re)enabled for thread scheduling purposes.
There is no requirement that a thread that releases a permit must have acquired that permit by calling {@link #acquire}. Correct usage of a semaphore is established by programming convention in the application.