@SuppressWarnings("unchecked")
    public static <K, V> MapPath<K, V, SimpleExpression<V>> $(Map<K, V> arg) {
        final Object current = aliasFactory.getCurrentAndReset();
        if (arg instanceof MapPath) {
            return (MapPath<K, V, SimpleExpression<V>>) arg; //NOSONAR
        } else if (arg instanceof ManagedObject) {
            return (MapPath<K, V, SimpleExpression<V>>) ((ManagedObject) arg).__mappedPath();
        } else {
            return (MapPath<K, V, SimpleExpression<V>>) current;
        }
    }
Convert the given alias to an expression

@param arg alias
@param <K>
@param <V>
@return expression
querydsl-core/src/main/java/com/querydsl/core/alias/Alias.java