设计模式 / 困惑

前段时间修改了一个通用存储过程类，这个类真的很强大(我修改以前就很强大，我改动了读取存储过程详细信息这个方法，比以前更快)，可以调用任意存储过程，有无output、返回table或返回1,0

部分代码：

public object Execute(string sp_name, string returnType, params object[] parameters)
        {
            try
            {
                SqlProcedure procedure = new SqlProcedure(sp_name);
                Sqlresult result;
                result = procedure.Call(parameters);
                switch (returnType.ToLower())
                {
                    case "int":
                        if (result.Value == 1)
                            return true;
                        return false;
                    case "table":
                        return result.dataSet;
                    case "output":
                        return result.Output;
                    case "all":
                        output = result.Output;
                        return result.dataSet;
                    default:
                        return null;
                }
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }

//调用如下 

using (DataSet ds = (DataSet)myDiseaseDetails.Execute("CommonSelect", "table", "select * from sclass where FClassID = 9"))
        {

//……
        }

没有用到商业逻辑层的get{},set{}之类的东西，这么写感觉破坏了三层规范，至今仍举棋不定，请指点一二