code: public void remove(String id) {
  		final Lock writeLock = lock.writeLock();
  		try {
  			writeLock.lock();
  			final int index = ids.indexOf(id);
  			if (index > -1) {
  				tasks.remove(index);
  				patterns.remove(index);
  				ids.remove(index);
  				size--;
  			}
  		} finally {
  			writeLock.unlock();
  		}
  	}
docs: 移除Task
  
  @param id Task的ID