public static <D> SimpleExpression<D> as(Expression<D> source, String alias) {
        return as(source, ExpressionUtils.path(source.getType(), alias));
    }
Create a {@code source as alias} expression

@param source source
@param alias alias
@return source as alias
querydsl-core/src/main/java/com/querydsl/core/types/dsl/Expressions.java