code: @SuppressWarnings("unchecked")
  	@Override
  	public V get(Object key) {
  		if (key == null || !(key instanceof Pair<?, ?>))
  			return null;
  		int index = keys.indexOf((Pair<T, I>) key);
  		if (index < 0)
  			return null;
  		return values.get(index);
  	}
docs: {@inheritDoc}