JDBC_Servlet: Data not found

[mithcool]

There is some problem when i check username and validate it against password from the database.After checking password from request.getParamter() and validating it against password column from the database it should say "You have been successfully login"... Perhaps I am getting my own else block message"Incorrect Password..." which means there is some problem with the password thing. Here is my servlet code

 response.setContentType("text/html");
        PrintWriter out= response.getWriter();
        String uname= request.getParameter("txtuname");
        String pass= request.getParameter("txtpass");
        Connection con =null;
        try {
            Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
            con=DriverManager.getConnection("jdbc:odbc:SQL","sa","mith1234");
            String select="select Password from sign_up where U_Name=\'"+uname+"\'";
            Statement st= con.createStatement();
            ResultSet rs= st.executeQuery(select);
            if(rs.next())
            {
                //out.println(pass);
                //out.println(rs.getString(1));
                if(rs.getString(1).equals(pass))
                {
                    out.println("You have been successfully logged in"+uname);
                }
               else 
                {
                    out.println("Incorrect Password");
                }
            }
        }
        catch(Exception e)
        {
            out.println(e);
        }
 
    }

When i say out.println(rs.getString(1)) it is returning me the data from the database.... Any kind of help appreciated!!!!

[Tolls]

First off, print out everything. Not just the password from the db (though see below about that) but the pass variable as well.
Stick marker prefix and suffixes on these printouts so you can see whether there is any extra whitespace.

Now, this should all be a single SQL statement. There should be no need to check the password at all in Java.
Also that query should be a PreparedStatement.
SO:

SELECT 1 FROM sign_up WHERE U_Name = ? AND password = ?

Then, if rs.next() is true you know that the username and password are valid. No need to let the password out of the database at all.

[doWhile]

Cross posted at JDBC_Servlet: Data not found

[mithcool]

thanks a lot friend... It is working perfectly fine n sorry for cross posting.... I wont cross post again.... thanks again...
Just a question: Now I also want to check whether the username is already there in the database which i can check through rs.getString() but i just want to through some javacript message for that. So how can i let javacript which is a client side scripting communicate with my servlet code???