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From "Michael Locasto" <loca...@cs.columbia.edu>
Subject Re: DB2 and servlet ??? Help !!!
Date Thu, 01 Aug 2002 18:22:19 GMT
...and I'm an idiot, because the SQL statement doesn't filter by them, so
it's quite inconsequential, really. :)

rs = stmt.executeQuery("SELECT empno from db2admin.employee");

Michael


----- Original Message -----
From: "Michael Locasto" <locasto@cs.columbia.edu>
To: "Tomcat Users List" <tomcat-user@jakarta.apache.org>
Sent: Thursday, August 01, 2002 2:16 PM
Subject: Re: DB2 and servlet ??? Help !!!


> Hi,
>
> Your parameter is '012', while it appears that the employeenumbers in
your
> database are more like:
>
> empno= 000150
>
>
> <quote>
>  BROWSER OUTPUT
> -------------------------------
> paramater passed is 012
>
> Count is0
> Found the JDBC driver
>
> Driver is properly loaded and registered
> Connection URL is good
> Retrieve some data from the database...
> Received results:
>
> Count is0
> God Please help
>
> </quote>
>
>
> Regards,
> Michael
>
>
>
> ----- Original Message -----
> From: <Nishant_Awasthi@progressive.com>
> To: "Tomcat Users List" <tomcat-user@jakarta.apache.org>
> Sent: Thursday, August 01, 2002 2:10 PM
> Subject: RE: DB2 and servlet ??? Help !!!
>
>
> >
> > I tried both ways
> > while(rs.next())
> > and
> > if(!rs.next())
> > both gives the same web browser output
> > ....
>
> ------------------------------------------------------------------------
> ------------
> >
> > Nishant Awasthi
> > Corporate Systems Development
> > Progressive Insurance
> >
> >
> >
> >
> >
> >
> >
> >
> >                     "Turner,
> >                     John"                To:     'Tomcat Users List'
> >                     <JTurner@AAS.
> <tomcat-user@jakarta.apache.org>
> >                     com>                 cc:     (bcc: Nishant
Awasthi)
> >                                          Subject:     RE: DB2 and
> servlet ??? Help !!!
> >                     08/01/2002
> >                     02:07 PM
> >                     Please
> >                     respond to
> >                     "Tomcat Users
> >                     List"
> >
> >
> >
> >
> >
> >
> >
> >
> > Nice catch!  You are right.  It should be
> >
> > if(rs.next())
> >
> > Or better yet...
> >
> > while(rs.next())
> >
> > John Turner
> > jturner@NOSPAM.aas.com
> >
> > -----Original Message-----
> > From: Wagoner, Mark [mailto:MWagoner@wildflavors.com]
> > Sent: Thursday, August 01, 2002 2:02 PM
> > To: 'Tomcat Users List'
> > Subject: RE: DB2 and servlet ??? Help !!!
> >
> >
> > I think you are attempting to output the value if there is nothing in
> the
> > result set.
> >
> > > if(!rs.next())
> >
> > The .next() method will return true if it was able to fetch a row.
You
> are
> > saying, "if there is no row then..."
> >
> > -----Original Message-----
> > From: Nishant_Awasthi@progressive.com
> > [mailto:Nishant_Awasthi@progressive.com]
> > Sent: Thursday, August 01, 2002 1:57 PM
> > To: Tomcat Users List
> > Subject: RE: DB2 and servlet ??? Help !!!
> >
> >
> >
> > Hello John
> >
> > "firstnme" is the correct column name...
> > What bugs me is if you see my servlet code which I am again
attaching...
> > I try to put try and ctach every where possible so that
> > I can at least printStackTrace() .
> > But to my surprise...I am not getting any exception...or stack
trace...
> > instead I am getting simple HTML output ...
> > I am attaching what
> > 1. I see in browser
> > 2. servlet code
> >
> >  BROWSER OUTPUT
> > -------------------------------
> > paramater passed is 012
> >
> >
> > Count is0
> > Found the JDBC driver
> >
> > Driver is properly loaded and registered
> > Connection URL is good
> > Retrieve some data from the database...
> > Received results:
> >
> > Count is0
> > God Please help
> >
> > --------------SERVLET CODE-------------
> > import java.sql.*;
> > import java.lang.*;
> > import java.io.*;
> > import java.io.*;
> > import javax.servlet.*;
> > import javax.servlet.http.*;
> >
> >
> > public class Ndb2Websphere extends HttpServlet {
> >
> >       Statement stmt;
> >                 ResultSet rs;
> >                int count =0;
> >
> >     public void doGet (HttpServletRequest req, HttpServletResponse
res)
> >      throws ServletException, IOException
> >     {
> >
> >
> >               res.setContentType("text/html");
> >
> >      ServletOutputStream out = res.getOutputStream();
> >
> >              String emp = req.getParameter("empnumber");
> >              out.println("paramater passed is "+emp +" <BR>");
> >                   out.println("<BR><BR>Count is"+ count);
> >                  try{
> >           Class.forName("COM.ibm.db2.jdbc.net.DB2Driver");
> >            out.println("<BR>Found the JDBC driver <BR>");
> >                      }
> >                      catch( Exception e)
> >                      {
> >           //        e.printStackTrace();
> >                             out.println("\nDriver class not found
> > exception");
> >              }
> >                      finally
> >                       {
> >                            out.println("<BR>Driver is properly loaded
> and
> > registered ");
> >                       }
> >
> >                try{
> >                 Connection con = null;
> >
> >
> >                            String url;
> >
> >                        out.println("<BR>Connection URL is  good");
> >
> >
> >                         try{
> >                    con = DriverManager.getConnection
> > ("jdbc:db2://10.3.13.34/SAMPLE","db2admin","db2pwd");
> >                         }
> >                         catch( Exception e4)
> >                         {
> >                                    e4.getMessage();
> >                 e4.printStackTrace();
> >                         }
> >
> >
> >               // retrieve data from the database
> >
> >                            out.println("<BR>Retrieve some data from
the
> > database...");
> >
> >                         try{
> >                 stmt = con.createStatement();
> >                                 rs = stmt.executeQuery("SELECT empno
> from
> > db2admin.employee");
> >           }
> >                          catch( Exception e5)
> >                          {
> >                                        e5.getMessage();
> >                 e5.printStackTrace();
> >                          }
> >
> >                    out.println("<BR>Received results:");
> >
> >                          try{
> >                                  if(!rs.next())
> >                                    {
> >                                                    count = count +1;
> >                                      String a = rs.getString(1);
> >
> >                            out.println(" empno is " + a );
> >                     out.println("<BR><BR>While Count is"+ count);
> >                    }
> >            }
> >                            catch( Exception e6)
> >                            {
> >                                    e6.printStackTrace();
> >                            }
> >                            out.println("<BR><BR>Count is"+ count);
> >
> >                rs.close();
> >                        stmt.close();
> >                             con.close();
> >
> >                 }
> >                 catch (SQLException e1)
> >                 {
> >                        e1.getMessage();
> >                        e1.printStackTrace();
> >                 }
> >                 catch( Exception e)
> >                 {
> >                        e.getMessage();
> >                e.printStackTrace();
> >                 }
> >                 finally
> >                 {
> >                         out.println("<BR>God Please help");
> >                 }
> >       }
> >     public void doPost (HttpServletRequest req, HttpServletResponse
res)
> >     throws ServletException, IOException
> >     {
> >         doGet(req,res);
> >     }
> >
> >
> > }
>
> ------------------------------------------------------------------------
> ----
> >
> > --------
> >
> > Nishant Awasthi
> >
> >
> >
> >
> >
> >
> >
> >
> >                     "Turner,
> >
> >                     John"                To:     'Tomcat Users List'
> >
> >                     <JTurner@AAS.
> <tomcat-user@jakarta.apache.org>
> >
> >                     com>                 cc:     (bcc: Nishant
Awasthi)
> >
> >                                          Subject:     RE: DB2 and
> servlet
> > ??? Help !!!
> >                     08/01/2002
> >
> >                     01:50 PM
> >
> >                     Please
> >
> >                     respond to
> >
> >                     "Tomcat Users
> >
> >                     List"
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> > Is "firstnme" the name of your column?  Or should it be "firstname"?
If
> > that's an error, there should be a SQLException thrown, but I don't
know
> > the
> > behavior fo DB2...it may just be that you get null back.  In any case,
> > besides printing a stack trace, I would output something to the
browser
> on
> > a
> > SQLException just so you can see what's going on.
> >
> > John Turner
> > jturner@NOSPAM.aas.com
> >
> > -----Original Message-----
> > From: Nishant_Awasthi@progressive.com
> > [mailto:Nishant_Awasthi@progressive.com]
> > Sent: Thursday, August 01, 2002 1:47 PM
> > To: soap-user@xml.apache.org; tomcat-user@jakarta.apache.org;
> > tomcat-dev@jakarta.apache.org
> > Subject: DB2 and servlet ??? Help !!!
> >
> >
> > Hello everyone...
> >
> > I am trying to connect the run a simple servlet to retrieve the
> > query results from DB2 database.
> >
> > 1. Before writing a servlet, I wrote a simple java file and was
> successful
> > in retrieving the
> > contents from DB2 UDB.
> >
> > 2. Then I just converted the same JAVA file into servlet by adding
> Servlet
> > API and syntax in it.
> > 3. It compiles fine.
> > 4. Then from a web page I try to pass one parameter to my servlet.
> > 5. The servlet doesnot retrieve any records from the database which
> > initially it was bringing
> >     when I wrote simple java file.
> >
> > Code of my servlet is as:
> > ----------------------
> > import java.sql.*;
> > import java.lang.*;
> > import java.io.*;
> >
> > public class Ndb2Tomcat{
> >
> >    public static void main(String args[]) {
> >
> >
> >   try{
> >      Class.forName("COM.ibm.db2.jdbc.net.DB2Driver");
> >      }
> >      catch( ClassNotFoundException e2)
> >      {
> >       System.out.println("\nJDBC Driver class not found exception");
> >      }
> >      catch( Exception e)
> >      {
> >        System.out.println("\nDriver class not found exception");
> >
> >     }
> >     try{
> >        Connection con = null;
> >       String url = "jdbc:db2://100.3.13.34/SAMPLE";
> >        con = DriverManager.getConnection(url,"db2admin", "db2pwd");
> >
> >         // retrieve data from the database
> >        System.out.println("Retrieve some data from the database...");
> >
> >        Statement stmt = con.createStatement();
> >        ResultSet rs = stmt.executeQuery("SELECT * from
db2admin.employee
> > order by firstnme");
> >
> >        System.out.println("Received results:");
> >
> >        while (rs.next())
> >        {
> >           String a = rs.getString(1);
> >           String str = rs.getString(2);
> >           System.out.print(" empno= " + a);
> >           System.out.print(" firstname= " + str);
> >           System.out.print("\n");
> >        }
> >        rs.close();
> >       stmt.close();
> >        con.close();
> >      }
> >      catch (SQLException e1)
> >      {
> >           e1.printStackTrace();
> >      }
> >
> >    }
> >
>
> ------------------------------------------------------------------------
> ----
> >
> >
> > --------
> >
> > Nishant Awasthi
> >
> >
> >
> >
> >
> > --
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