Accessing postgresql record using servlet

Hello every body,
I am trying to access the postgresql database using servlet. But I found the error of ClassNotFound exception: org.postgresql.Driver. One thing more I am using eclipse ide. I have used the postgresql-8.1-404.jdbc3 driver. And I have set it on class path in eclipse.
package dbservlet.example;
import java.io.*;
import java.sql.*;
import java.text.*;
import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class DbServletExample1 extends HttpServlet{
     public String getServletInfo() {
          return "Servlet connects to PostgreSQL database and displays result of a SELECT";
     private Connection dbcon; // Connection for scope of DbServletExample1
     public void init(ServletConfig config) throws ServletException { // "init" sets up a database connection
          String loginUser = "ali";
          String loginPasswd = "ali";
          String loginUrl = "jdbc:postgresql://127.0.0.1:5432/ali"; // Load the PostgreSQL driver
          try{
               Class.forName("org.postgresql.Driver");
               dbcon = DriverManager.getConnection(loginUrl, loginUser, loginPasswd);
          catch (ClassNotFoundException ex){
               System.err.println("ClassNotFoundException: " + ex.getMessage());
               throw new ServletException("Class not found Error");
          catch (SQLException ex){
               System.err.println("SQLException: " + ex.getMessage());
     // Use http GET
     public void doGet(HttpServletRequest request, HttpServletResponse response)
                         throws IOException, ServletException {
          response.setContentType("text/html"); // Response mime type
          PrintWriter out = response.getWriter(); // Output stream to STDOUT
     out.println("<HTML><Head><Title>Db Servelt Example</Title></Head>");
     out.println("<Body><H1>Example of Servlet with Postgres SQL</H1>");
     try {                // Declare our statement
          Statement statement = dbcon.createStatement();
          String query = "SELECT empid, name, dept, "; // Perform the query
          query += " jobtitle ";
          query += "FROM employee ";
          ResultSet rs = statement.executeQuery(query);
          out.println("<table border>");
          while (rs.next()) {      // Iterate through each row of rs
               String m_id = rs.getString("empid");
               String m_name = rs.getString("name");
               String m_dept = rs.getString("dept");
               String m_jobtitle = rs.getString("jobtitle");
               out.println("<tr>" +
                                   "<td>" + m_id + "</td>" +
                                   "<td>" + m_name + "</td>" +
                                   "<td>" + m_dept +"</td>" +
                                   "<td>" + m_jobtitle + "</td>" +
                              "</tr>");
          out.println("</table></body></html>");
          statement.close();
     catch(Exception ex){
          out.println("<HTML>" +
                         "<Head><Title>" +
                         "Bedrock: Error" +
                         "</Title></Head>\n<Body>" +
                         "<P>SQL error in doGet: " +
                         ex.getMessage() + "</P></Body></HTML>");
          return;
     out.close();
and web.xml file is
<web-app>
          <database>
               <driver>
               <type>org.postgresql.Driver</type>
          <url>jdbc:postgresql://127.0.0.1:5432/ali</url>
          <user>ali</user>
          <password>ali</password>
               </driver>
          </database>
          <servlet>
          <servlet-name>DbServletExample1</servlet-name>
          <servlet-class>dbservlet.example.DbServletExample1</servlet-class>
          </servlet>
          <servlet-mapping>
          <servlet-name>DbServletExample1</servlet-name>
          <url-pattern>/db11</url-pattern>
          </servlet-mapping>
</web-app>
Thanks in advance

That web.xml doesn't look right to me.
what's that <database> tag? I would only expect to see a <resource-ref> in the web.xml.
I would not touch the server.xml. Create a context.xml and put it in your META-INF directory. That should look like this:
<?xml version="1.0" encoding="UTF-8"?>
<Context path="/your-path" reloadable="true" crossContext="true">
    <Resource name="jdbc/your-jndi"
              auth="Container"
              type="javax.sql.DataSource"
              username="your-username"
              password="your-password"
              driverClassName="your-driver-class"
              url="your-url"
              maxActive="10"
              maxWait="60000"
              removeAbandoned="true"
              removeAbandonedTimeout="60000"/>
</Context>%

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<b>[This thread was migrated from the On Demand Developer Forum in the old Siebel Community] </b>
algocode
New Contributor
I try connecting to Revenue records with web services using the same user
ID with which I'm able to create Service Revenue Details information from
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Product: General: IT Organizations and Processes
10-27-2006 11:25 AM
Re: how to access Revenue records
algocode
New Contributor
Inside a class extending System.Web.UI.Page, I use the
secure.crmondemand.com/OnDemand/user/account.wsdl?WSDLOBJ=account web
service to
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2. Create an AccountWS_AccountQueryPage_Input object;
3. Retrieve an AccountWS_AccountQueryPage_Output object;
These are the three methods involved:
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objListOfAccount[0].ListOfOpportunity[0].CurrencyCode = "";
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objListOfAccount[0].ListOfRevenue[0].OpportunityName = "";
objListOfAccount[0].ListOfRevenue[0].NumberOfPeriods = "";
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int intAccountCount = 1;
int intOpportunityCount = 20;
int intRevenueCount = 10;
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rtnListOfAccount[intAccIdx] = new Account1();
rtnListOfAccount[intAccIdx].ListOfOpportunity =
new
Opportunity[intOpportunityCount];
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for (int intOppIdx = 0; intOppIdx < intOpportunityCount;
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rtnListOfAccount[intAccIdx].ListOfOpportunity[intOppIdx] =
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rtnListOfAccount[intAccIdx].ListOfRevenue[intRevIdx] =
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catch (Exception objExcep)
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Session session)
AccountWS_AccountQueryPage_Output qpoutput = null;
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try
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catch (Exception e)
Response.Write("<br/><br/>" + e.InnerException);
Response.Write("<br/><br/>" + e.Message);
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10-27-2006 02:31 PM
Re: how to access Revenue records
algocode
New Contributor
I found another way to access Revenue records. Instead of accessing the
ListOfRevenue field of the Account web service, I access the ListOfProduct
field of the Opportunity web service. I also instantiate Opportunity2
objects so that the code to get a list of opportunities and products
(containing revenue fields) becomes
Opportunity2[] rtnListOfOpportunity = new
Opportunity2[intOpportunityCount];
try
for (int intOppIdx = 0; intOppIdx < intOpportunityCount;
intOppIdx++)
rtnListOfOpportunity[intOppIdx] = new Opportunity2();
rtnListOfOpportunity[intOppIdx].ListOfProduct =
new Product[intProductCount];
for (int intProdIdx = 0; intProdIdx < intProductCount;
intProdIdx++)
rtnListOfOpportunity[intOppIdx].ListOfProduct[intProdIdx] =
new Product();
return rtnListOfOpportunity;
10-28-2006 11:17 AM
Re: how to access Revenue records
Echo
Valued Contributor
Weird. I'm not a big C# programmer but the code looks right. I'm curious -
could you post some soap loads of the request. I'm wondering if there's
something weird going on with the proxy.
10-31-2006 12:00 AM

I Assume the following is your sample data
Table Name: Tab1
RegID CustID Registration_Start      Registration_End
1      1      01/04/2005           07/04/2005
2      2      01/03/2005           29/05/2005
3      1      21/03/2005           29/03/2005
4      1      01/03/2005           21/03/2005
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Regards,
Somu

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request.getRemoteUser()

Displaying a set of records using jstl

hi i am new to jstl.my requirement is i want to display a set of records from my database using jstl.for eg i want to display 50 records per page and i want to navigate to other records using next and prevoius buttons and i need to put view and edit buttons in that page.can anybody give me a solution for this.urgent

You may try the paging taglib ...
http://www.servletsuite.com/servlets/pagertag.htm

Problem accessing HTML pages using Tomcat 4

I am very new to programming. I have created an html file (ThreeParamsForm.html) and placed it in development directoy. I am unsure of how to access that file. When i am typing http://localhost/ThreeParamsForm.html it is giving me HTTP Status 404 error. I have tried using servlets in similar way it is working fine. Please help.....

did you include the port number if other than 80 ?
i.e. http:\\localhost:8080\whatever

When to use jsp,and when to use servlet?

I think that jsp and servlet can realize the same functions, because when run a jsp, it is transferred to a servlet program, so when to use jsp and when to use servlet?
I am now developing the input interface for a website, I just use jsp and javabean to connect to weblogic and database, and I didn't use servlet, Is there any unseemliness?
Thank you!

IMHO I use servlets to control the flow between my jsp's based on a number of factors in a webapp. For instance, user authorization. If a user has the authorization to conduct various administrative functions on an application (like change user rights, reset passwords etc) they will have access to specific buttons or links on some screens that others will not. I use servlets to establish what access rights a user has and direct them to the appropriate pages. I also use servlets to test data validity on form input screens. I know that I can also do this with JavaScript but that can be disabled by the client and in order to prevent that I also double check the form input from a servlet. All my jsp's do is display the results of a business process (which is held in a JavaBean or EJB) and the servlets act as the controllers for the application, connecting to multiple databases, verifying application state, flow control etc. I try to keep the jsp as simple as possible as some of them are maintained by html developers who lack the necessary experience to write java code. I hope this helps.

PageNotFound when using servlets as clients for EJB

Can anyone help me? I have a container managed EJB. I'm using servlets as my client. I placed my EJB's in a jar file and my servlets and html pages in a WAR file. I deployed them using J2EE's deploytool. I can access my html files but not my servlet files. It always says file not found or a 405 error (resource not allowed) I access my servlet this way...
http://localhost:8000/ReservationContextRoot/ReservationAlias
my web.xml file looks like the following:
<?xml version="1.0" encoding="Cp1252"?>
<!DOCTYPE web-app PUBLIC '-//Sun Microsystems, Inc.//DTD Web Application 2.2//EN' 'http://java.sun.com/j2ee/dtds/web-app_2.2.dtd'>
<web-app>
<display-name>ReservationWAR</display-name>
<description>no description</description>
<servlet> <servlet-name>ReservationServlet</servlet-name>
<display-name>ReservationServlet</display-name>
<description>no description</description>
<servlet-class>ReservationServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>ReservationServlet</servlet-name>
<url-pattern>ReservationAlias</url-pattern>
</servlet-mapping>
<session-config>
<session-timeout>30</session-timeout>
</session-config>
<resource-ref>
<description>no description</description>
<res-ref-name>jdbc/ReservationDB</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>
<ejb-ref> <description>no description</description>
<ejb-ref-name>ejb/Reservation</ejb-ref-name>
<ejb-ref-type>Entity</ejb-ref-type>
<home>ReservationHome</home>
<remote>Reservation</remote>
</ejb-ref>
</web-app>

Are you sure your servlet class itself can run without problem? Try debug in the these steps:
1. Change your servlet to simply output some HTML text, so you can be sure tomcat can get to your servlet. If this is OK, it means the servlet itself has problem, probably the EJB stuff.
2. Make sure the EJB container is running.
3. Make your servlet a standalone client (not a servlet) and see if it can run. Pay attention to how you do JNDI lookup of the EJB.
Yi

Accessing postgresql record using servlet

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