System.Data.SqlClient.SqlConnection.Dispose C# (CSharp) Method

        override protected void Dispose(bool disposing) { }
    }

        public static string SP_Tender_FindRecord(string ProcessId, ref DataSet ReturnDs)
        {
            SqlConnection sqlConn = new SqlConnection();  //defines database connection
            SqlCommand sqlCmd = new SqlCommand();  //defines what to do
            SqlDataAdapter sqlAdap = new SqlDataAdapter();

            try
            {
                sqlConn.ConnectionString = ConfigurationManager.ConnectionStrings["AMS_MasterConnectionString"].ToString();
                sqlConn.Open();

                sqlCmd.CommandText = "SP_Tender_FindRecord";
                sqlCmd.CommandType = CommandType.StoredProcedure;
                sqlCmd.Connection = sqlConn;

                SqlParameter parm1 = new SqlParameter("@ProcessId", SqlDbType.VarChar);
                parm1.Value = ProcessId;
                parm1.Direction = ParameterDirection.Input;
                sqlCmd.Parameters.Add(parm1);

                sqlAdap.SelectCommand = sqlCmd;
                sqlAdap.Fill(ReturnDs);

                return string.Empty;

            }
            catch (Exception err)
            {
                return err.Message;
            }
            finally
            { sqlConn.Close(); sqlConn.Dispose(); sqlAdap.Dispose(); }
        }