Re: database servlet [Scanned by Yellow Pages PostMaster]

Charles Chen Tue, 17 Oct 2000 09:39:58 -0700
Contact:   Tel: 2726  -  New Media Systems, 1st Floor South, Queens Walk


I vaguely remember that the connection string is
"jdbc:odbc:JdbcOdbcBridge:Books" but I might be wrong. Check this out anyway.

In general, you should be able to see the exception when your servlet is loaded
if that connection string is wrong. If you are using JWS 2.0 (looks ilke it) you
can login as admin and try to load your servlet from there. If the connection
string is wrong, it will fail to load your servlet.


Charles







Ying Sun <[EMAIL PROTECTED]> on 10/17/2000 05:10:37 PM

To:        [EMAIL PROTECTED]
cc:         (bcc: Charles Chen/YellowPages)
From:      Ying Sun <[EMAIL PROTECTED]>, 17 October 2000, 5:10 p.m.

Re: database servlet  [Scanned by Yellow Pages PostMaster]


Hi friends,

I create the data source Books.mdb as a System DSN on my machine,and I
try to use JdbcServlet to retrieve the data from the Arthurs table.

when I invoke it using http://localhost:8080/servlet/JdbcServlet,it gave
me blank page.I use java web server2.0.

Can someone give me a idea?

thanks.

import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.sql.*;

/**
 * JdbcServlet reads customer information from an ODBC data
 * source and presents it to the client in an HTML table.
 *
 */
public class JdbcServlet extends HttpServlet
{
  //database connection is shared by all requests
  static Connection dbConn;

  /**
   * init method is called when servlet is initialized.
   * Establishes a database connection when servlet is initially
   * loaded that can be shared across all requests.
   */
  public void init(ServletConfig config) throws
    ServletException
  {
    super.init(config); //pass ServletConfig to parent

    try
    {
      //load JDBC-ODBC Bridge driver
      Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
      //establish database connection to Books using ODBC
      dbConn = DriverManager.getConnection(
        "jdbc:odbc:Books");
    }
    catch (ClassNotFoundException e) //Class.forName throws
    {
      System.out.println("JDBC-ODBC bridge not found!");
      return;
    }
    catch (SQLException e) //DriverManager.getConnection throws
    {
      System.out.println("SQL exception thrown in init!");
      return;
    }
  }


  /**
   * doGet method is called in response to a GET request
   */
  public void doGet(HttpServletRequest request,
    HttpServletResponse response) throws ServletException,
    IOException
  {
    try
    {
      response.setContentType("text/html"); //returns HTML

      //get handle to output stream
      PrintWriter out = response.getWriter();

      //create statement
      Statement stat = dbConn.createStatement();
      //query database for result set
      ResultSet customers = stat.executeQuery(
        "SELECT AuthorID, FirstName, LastName, YearBorn FROM " +
        "Authors");

      //generate HTML document to return to client
      out.println("<HTML>");
      out.println("<HEAD><TITLE>author list</TITLE></HEAD>");
      out.println("<BODY>");
      out.println("<H2>author List</H2>");
      out.println("<TABLE BORDER=1>"); //create an HTML table
      out.println("<TR><TH>Author ID</TH>");
      out.println("<TH>first Name</TH>");
      out.println("<TH>last name</TH>");
      out.println("<TH>year born</TH></TR>");

      while (customers.next()) //iterate through all records
      {
        //add a table row for each record
        out.println("<TR><TD>" +
          customers.getInt("AuthorID")+ "</TD><TD>" +
          customers.getString("FirstName") + "</TD><TD>" +
          customers.getString("LastName") + "</TD><TD>" +
          customers.getString("YearBorn") + "</TD></TR>");
      }

      out.println("</TABLE>");
      out.println("</BODY></HTML>");
      out.close();
    }
    catch (Exception e)
    {
      e.printStackTrace();
    }
  }

  /**
   * Tells the server about this servlet
   */
  public String getServletInfo()
  {
    return "Sample JDBC servlet";
  }
}

___________________________________________________________________________
To unsubscribe, send email to [EMAIL PROTECTED] and include in the body
of the message "signoff SERVLET-INTEREST".

Archives: http://archives.java.sun.com/archives/servlet-interest.html
Resources: http://java.sun.com/products/servlet/external-resources.html
LISTSERV Help: http://www.lsoft.com/manuals/user/user.html

___________________________________________________________________________
To unsubscribe, send email to [EMAIL PROTECTED] and include in the body
of the message "signoff SERVLET-INTEREST".

Archives: http://archives.java.sun.com/archives/servlet-interest.html
Resources: http://java.sun.com/products/servlet/external-resources.html
LISTSERV Help: http://www.lsoft.com/manuals/user/user.html
Re: database servlet [Scanned by Yellow Pages PostMaster]

Reply via email to
