Simple Named Lock

NamedLock.java

private class NamedLock<T> {
  private HashSet<T> locks = new HashSet<T>();

  public void lock(final T name) {
    synchronized (locks) {
      while (locks.contains(name)) {
        locks.wait();
      }
      locks.add(name);
    }
  }

  public void unlock(final T name) {
    synchronized (locks) {
      locks.remove(name);
      locks.notifyAll();
    }
  }
}