Question

I am trying a servlet that puts the data into the database:derbi (that comes packed with netbeans). When a user clicks to submit data,the request follows to the FormHandler servlet (given below) If any of the text-field was empty the request follows to another servlet ErrorServlet and if every thing was fine the request follows to the Registered servlet. But before the request follows to the Registered Servlet there is a small code that is written to insert the data into the database (After this code the the user views the success page,that he has been registered).

Now the problem : The user fills all the text fields in the form and clicks submit. When he clicks submit,he sees the success page displaying Registered Successfully . But when i query the databse, i see that the data wasn’t submitted to the databse. The rows and columns are empty ! I don’t understand the reason for this .

Code for FormHandler.java :

package FormHandler;

import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.util.LinkedList;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import javax.sql.DataSource;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;

public class FormHandler extends HttpServlet {
  @Override
         public void doGet(HttpServletRequest request,HttpServletResponse response) throws ServletException,IOException {
    
}

@Override
        public void doPost(HttpServletRequest request,HttpServletResponse response) throws ServletException,IOException {
    
    String name = request.getParameter("Name");
    String email = request.getParameter("Email");
    String password = request.getParameter("Password");
    
    LinkedList list = new LinkedList();
    
    if(name.compareTo("") == 0 || email.compareTo("") == 0 || email.compareTo("") == 0) {
        list.add("One or more field's' left blank");
        request.setAttribute("ErrorList", list);
        RequestDispatcher rd = request.getRequestDispatcher("ErrorServlet.view");
        rd.forward(request, response);
    } else {
        try {
            Context context = new InitialContext();
            DataSource ds = (DataSource)context.lookup("java:comp/env/jdbc/MyDatasource");
            Connection connection = ds.getConnection();
           String sqlStatement = "INSERT INTO INFORMATION VALUES('" + name + "'," + "'" + email + "'," + "'" + password + "')";  
               PreparedStatement statement = connection.prepareStatement(sqlStatement);
               ResultSet result = statement.executeQuery();     
        }catch(Exception exc) {
            System.out.println(exc);
        }
        request.setAttribute("Data", list);
        RequestDispatcher rd = request.getRequestDispatcher("Registered.view");
        rd.forward(request, response);
      }
    
    
}

}

XML file:

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="3.0" xmlns="http://java.sun.com/xml/ns/javaee"  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd">
<servlet>
    <servlet-name>FormHandler</servlet-name>
    <servlet-class>FormHandler.FormHandler</servlet-class>
</servlet>
<servlet>
    <servlet-name>Registered</servlet-name>
    <servlet-class>FormHandler.Registered</servlet-class>
</servlet>
<servlet>
    <servlet-name>ErrorServlet</servlet-name>
    <servlet-class>FormHandler.ErrorServlet</servlet-class>
</servlet>
<servlet-mapping>
    <servlet-name>FormHandler</servlet-name>
    <url-pattern>/FormHandler.do</url-pattern>
</servlet-mapping>

<resource-ref>
    <res-ref-name>jdbc/MyDatasource</res-ref-name>
    <res-type>javax.sql.DataSource</res-type>
    <res-auth>Container</res-auth>
    <res-sharing-scope>Shareable</res-sharing-scope>
</resource-ref>

<servlet-mapping>
    <servlet-name>Registered</servlet-name>
    <url-pattern>/Registered.view</url-pattern>
</servlet-mapping>
<servlet-mapping>
    <servlet-name>ErrorServlet</servlet-name>
    <url-pattern>/ErrorServlet.view</url-pattern>
</servlet-mapping>
<session-config>
    <session-timeout>
        30
    </session-timeout>
</session-config>

Html File :Code for html file

Note : I have already made a connection to database

Answer 1

I think you are getting somewhere a :

 java.sql.SQLException: No ResultSet was produced

because executing your UPDATE query with executeQuery() actually returns no resultset

Use:

 statement.executeUpdate();