try
            {
                con=DriverManager.getConnection("jdbc:MySQL://127.0.0.1:3306/Phone_Contacts", "root","fzg125009");
                if(radio_name.isSelected())
                {
                    pre=con.prepareStatement("SELECT DISTINCT * FROM Contact WHERE name Like '"+field_name.getText()+"%'");
                }
                else if(radio_phone.isSelected())
                {
                    pre=con.prepareStatement("SELECT DISTINCT * FROM Contact WHERE mobile Like '"+field_phone.getText()+"%'");
                }
                rs=pre.executeQuery();
                row=new CachedRowSetImpl();
                row.populate(rs);    
                if(row.wasNull())//这个不能被执行，所以这样检测不可以
                {
                    text.append("Sorry,无此记录!\n");
                }
                con.close();
                while(row.next())
                {
                    text.append(row.getString(1)+"\t");
                    text.append(row.getString(2)+"\n");
                }
            }
            catch (SQLException error)
            {
                System.out.println("error!");
            }