THIS IS A NO GUI TEST. GUI COMES AFTER THIS IS DONE. " i hope to learn from this so i can use it on the gui " :D

i have my database : friends , table : info , values : (name ) : dragon , (address) : china
i have no idea how to do the password and user name check on this.

-------------------------------- MY Main class ------------ or tester -----------------------

package Main;

import java.util.*;
import java.sql.*;
import DBAccess.DBUtil;
/**
 *
 * @author christian @modified by moraxus
 */
public class Test {

    public static void main(String araguy[]) throws SQLException
    {
        String a,b,na,nu,np = null,cu,cp,da ;

        Scanner scn = new Scanner(System.in);
        DBUtil dbu = new DBUtil();

        System.out.println("Enter Username : ");
        a = scn.nextLine();
        System.out.println("Enter password : ");
        b = scn.nextLine();

  /*-----------------------------------------------------------------------------*/      

ResultSet rs = dbu.retrieve("Select * from info where name='"+ a +"' and address='"+b+"';");

 String f = rs.getString("name");
 String e = rs.getString("address");


if (a.equals(f)& b.equals(e))

{
System.out.println("Hello " + a + " Welcome to your account");     
System.out.println( " What would be your next action ?");
System.out.println( "[cu] Change username " );
System.out.println( "[cp] Change password " );
System.out.println( "[da] Delete account ");
cu = scn.nextLine();    
switch ( cu ){
case "cu":
System.out.println( "Enter new username" );
    nu = scn.nextLine();
dbu.alter("update info set name ='"+nu+"' where name ='"+a+"';");    
break;

case "cp":
System.out.println( "Enter new password" );
np = scn.nextLine();
dbu.alter("update info set name ='"+np+"' where name ='"+b+"';");    
break;

case "da":
dbu.delete("delete from info where name='"+a+"';");    
break;
}
}

else
{ System.out.println("NO Records of your account ! : would you like an" + "account ?");


System.out.println( "[y] Yes " );
System.out.println( "[n] No" );
na = scn.nextLine();    
switch ( na ){
case "y":
System.out.println( "Enter username" );
    nu = scn.nextLine();
System.out.println("Enter password");
    np = scn.nextLine();

dbu.insert("insert into info values('"+ nu +"','"+np+"');");

case "n":
    break;

}




/*----------------------------------------------------------------------------*/


/*------------------------------------------------------------------------------------*/
 dbu.disconnect();



}
 }


}

-------------------------------------- my subclass ( with the connectors and stuff ) ---------------------------

package DBAccess;

import java.sql.*;

/**
 *
 * @author christian modified by moraxus
 */
public class DBUtil {

   /*
    * 0. load the driver
    * 1. connect to the database
    * 2. define the database to use
    * 3. manipulate the tables
    */
  Connection con;
  Statement stmt;  
  PreparedStatement ob = null;


  public DBUtil()
  {
    // 1.  load the sql driver
           try {
                    Class.forName("com.mysql.jdbc.Driver");
               } 
           catch (ClassNotFoundException ex) {
                    System.err.println(ex.getMessage());
                }

            String url = "jdbc:mysql://127.0.0.1/friends";
            String userid = "root";
            String pass = "root";
            try  
            {
                con = DriverManager.getConnection(url, userid, pass);
                stmt = con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_READ_ONLY);

            } 
        catch (SQLException ex) 
            {
                System.err.println(ex.getMessage());
            }
  }
 /*-------------------------------------------------------------------------------------*/ 
  public ResultSet retrieve(String commandStr)
  {     
      try
      {
        ResultSet rs = stmt.executeQuery(commandStr);
        return rs;
      }
      catch(SQLException ex) 
      {
          System.err.println(ex.getMessage());
          return null;
      }

  }

  public int insert(String commandStr)
  {     
      try
      {
        return stmt.executeUpdate(commandStr);

      }
      catch(SQLException ex) 
      {
          System.err.println(ex.getMessage());
          return 0;
      }

  }

   public int alter(String commandStr)
  {     
      try
      {
        return stmt.executeUpdate(commandStr);

      }
      catch(SQLException ex) 
      {
          System.err.println(ex.getMessage());
          return 0;
      }

  }

     public int delete(String commandStr)
  {     
      try
      {
        return stmt.executeUpdate(commandStr);

      }
      catch(SQLException ex) 
      {
          System.err.println(ex.getMessage());
          return 0;
      }

  }

  public void disconnect()
  {
      try
      {
        stmt.close();
        con.close();
      }
      catch( SQLException ex)
      {
           System.err.println(ex.getMessage());
      }

  }

}

Hi,

could you by any chance give us a bit more insight into what you are struggling with? You seem to be able to get data and compare it already?