tomcat-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Luke Vanderfluit <l...@chipcity.com.au>
Subject jdbc servlets and jsp
Date Sun, 07 Sep 2003 21:53:21 GMT
Hi,

I'm having a few probs (fun) getting jdbc to work in servlets and jsp,
tomcat in other words.

I've successfully got jdbc working with postgresql in a regular java
class. 

I have tried using the same code adapted to a servlet and jsp to get a
database connection happening from there, however no luck,

Is there anything I need to set up in server.xml or web.xml before it
can work?

here is my jsp and servlet code:
################################
jsp file
-=-=-=-=
<html>
<head>
</head>
<%@ page language="java" import="java.sql.*" %>
<body>
<%

Class.forName("org.postgresql.Driver");
Connection myConn=DriverManager.getConnection("jdbc:postgresql:mboard",
"luke", "");

%>
</body>
</html>
=-=-=-=-=-=-=-=-=-=-=-=-=-=
servlet code
=-=-=-=-=-=-=-=-=-=-=-=-=-=
import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.sql.*;
import java.text.DateFormat;

/**
 * ShowEmployees creates an HTML table containing a list of all
 * employees (sorted by last name) and the departments to which
 * they belong.
 */
public class ShowEmployees extends HttpServlet
{
  Connection dbConn = null;

  /**
   * Establishes a connection to the database.
   */
  public void init() throws ServletException
  {
    String jdbcDriver = "org.postgresql.Driver";
    String dbURL = "\"jdbc:postgresql:mboard\", \"luke\", \"\"";

    try
    {
      Class.forName("org.postgresql.Driver").newInstance(); //load
driver
      dbConn = DriverManager.getConnection("jdbc:postgresql:megaboard",
"luke", ""); //connect
    }
    catch (ClassNotFoundException e)
    {
      throw new UnavailableException("JDBC driver not found:" +
        jdbcDriver);
    }
    catch (SQLException e)
    {
      throw new UnavailableException("Unable to connect to: " +
        dbURL);
    }
    catch (Exception e)
    {
      throw new UnavailableException("Error: " + e);
    }
  }

  /**
   * Displays the employees table.
   */
  public void service(HttpServletRequest request,
    HttpServletResponse response) throws ServletException,
    IOException
  {
    response.setContentType("text/html");

    PrintWriter out = response.getWriter();

    try
    {
      //join EMPLOYEE and DEPARTMENT tables to get all data
      String sql = "select * from message;";

      Statement stmt = dbConn.createStatement();
      ResultSet rs = stmt.executeQuery(sql);

      out.println("<HTML>");
      out.println("<HEAD><TITLE>Show Employees</TITLE></HEAD>");
      out.println("<BODY>");
      out.println("<TABLE BORDER=\"1\" CELLPADDING=\"3\">");
      out.println("<TR>");
      out.println("<TH>Name</TH>");
      out.println("<TH>Department</TH>");
      out.println("<TH>Phone</TH>");
      out.println("<TH>Email</TH>");
      out.println("<TH>Hire Date</TH>");
      out.println("</TR>");

      while (rs.next())
      {
        out.println("<TR>");

        out.println("<TD>" + rs.getString("resusername") + "</td>");

        out.println("</TR>");
      }

      out.println("</TABLE>");
      out.println("</BODY></HTML>");

      rs.close();
      stmt.close();
    }
    catch (SQLException e)
    {
      out.println("<H2>Database currently unavailable.</H2>");
    }

    out.close();
  }
}

any help would be greatly appreciated.
thanks,
kind regards
Luke

-- 

====================================
"when my computer smiles, I'm happy"
===============================.~ ~,
Luke Vanderfluit               |'/']
Mobile: 0421 276 282            \~/`


Mime
View raw message