LockingLock.java

import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReadWriteLock;
import java.util.concurrent.locks.ReentrantReadWriteLock;

public class Locking
{
	private static final ReadWriteLock locker = new ReentrantReadWriteLock();

	public void lock()
	{
		Lock lock = locker.readLock();

		try { lock.lock(); }
		finally { lock.unlock(); }
	}
}

Locking.locker.readLock().lock();