code: @Override
  	public final void unlock(int handle) throws DataStoreException 
      {
          if (SAFE_MODE) checkHandle(handle);
          if (locks.flip(handle))
          {
              locks.flip(handle); // Restore state
              throw new DataStoreException("Handle was not locked : "+handle);
          }
      }
docs: /*
  (non-Javadoc)
  @see net.timewalker.ffmq4.utils.store.LinkedDataStore#unlock(int)