Request Attributes not clearing after request is over

Request Attributes not clearing after request is over - java

I am having a problem with request attributes in my jsp, I am using the mvc pattern and setting a request attribute and forwarding to a jsp from the servlet. The application is a banking application, the goal is to use the customer id to get the customer by customer id pass it to the Account class to collect all of the accounts of the user. I have this problem solved I can get the account information and process it without any issue. The problem I am having is when I close the page and run again from the beginning I find that when I get to the table it is still putting in the information from the previous request as well as the new information that I am requesting. Like So:
()
My code is as follows for the servlet that directs me to the jsp and the jsp that I use the information into.
AccountServlet.java:
package com.ChattBank.controller;
import com.ChattBank.business.Account;
import com.ChattBank.business.Accounts;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
/**
*
* #author AARONS
*/
public class AccountServlet extends HttpServlet {
/**
* Processes requests for both HTTP <code>GET</code> and <code>POST</code>
* methods.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
try (PrintWriter out = response.getWriter()) {
/* TODO output your page here. You may use following sample code. */
out.println("<!DOCTYPE html>");
out.println("<html>");
out.println("<head>");
out.println("<title>Servlet AccountServlet</title>");
out.println("</head>");
out.println("<body>");
out.println("<h1>Servlet AccountServlet at " + request.getContextPath() + "</h1>");
out.println("</body>");
out.println("</html>");
}
}
// <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
/**
* Handles the HTTP <code>GET</code> method.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
#Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
//HttpSession session = request.getSession();
String action = request.getParameter("action");
if (action == null) {
request.getRequestDispatcher("/Welcome.jsp").forward(request, response);
} else if (action.equals("view")) {
Accounts acct = new Accounts();
ArrayList<Account> list = new ArrayList();
try {
acct.setCustAccounts(request.getParameter("id"));
list.addAll(acct.getCustAccounts());
System.out.println(request.getParameter("id"));
} catch (SQLException ex) {
Logger.getLogger(Accounts.class.getName()).log(Level.SEVERE, null, ex);
}
request.setAttribute("acctList", list);
request.getServletContext().getRequestDispatcher("/accounts.jsp").forward(request, response);
}
}
/**
* Handles the HTTP <code>POST</code> method.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
#Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
String action = request.getParameter("action");
String custId = request.getParameter("custID");
if (action == null) {
request.getRequestDispatcher("/Welcome.jsp").forward(request, response);
}
}
/**
* Returns a short description of the servlet.
*
* #return a String containing servlet description
*/
#Override
public String getServletInfo() {
return "Short description";
}// </editor-fold>
}
accounts.jsp:
<%--
Document : accounts
Created on : Jun 25, 2014, 12:24:38 AM
Author : Richard Davy
--%>
<%#page import="java.util.ArrayList"%>
<%#page import="com.ChattBank.business.Account"%>
<%#page import="com.ChattBank.business.Accounts"%>
<%#page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Your Accounts</title>
</head>
<body>
<%
ArrayList<Account> list = new ArrayList();
list.addAll((ArrayList)request.getAttribute("acctList"));
for (Account custAccount : list) {
System.out.println("From JSP: " + custAccount.getCustId() + " " + custAccount.getAcctNo() + " " + custAccount.getAcctType() + " " + custAccount.getBalance());
System.out.println("Getting Object From Section");
}
%>
<h1>You Made It Here!</h1>
<table border="1" width="2" cellspacing="5" cellpadding="2">
<thead>
<tr>
<th colspan="10">Your Chatt Accounts</th>
</tr>
</thead>
<tbody>
<% for (int i = 0; i < list.size(); i++){ %>
<tr>
<td colspan="2">Account: </td>
<td colspan="2"><%= list.get(i).getCustId() %></td>
<td colspan="2"><%= list.get(i).getAcctNo() %></td>
<td colspan="2"><%= list.get(i).getAcctType() %></td>
<td colspan="2"><%= list.get(i).getBalance() %></td>
</tr>
<% } %>
<% list.clear(); %>
</tbody>
</table>
<p>Thank you for your business!</p>
</body>
</html>
I am not really sure what is going on I started with session attributes and thought that was my issue, so I turned to using request attributes. But I am still facing the same issue. I was under the impression that the request attribute only lasted per that request but it seems that the information is still being carried through. Any suggestions?

The funny thing about this issue is that it wasn't anything to do with the request attribute variables. Since I was instantiating a list of objects in a class that list of objects was persisting and just being added to. I think this is mostly because I was using an ArrayList which is able to be appended to. Instead of re-writing the entire class to figure out some work around I included a try{}finally{} statement like so:
package com.ChattBank.controller;
import com.ChattBank.business.Account;
import com.ChattBank.business.Accounts;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
/**
*
* #author AARONS
*/
public class AccountServlet extends HttpServlet {
/**
* Processes requests for both HTTP <code>GET</code> and <code>POST</code>
* methods.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
try (PrintWriter out = response.getWriter()) {
/* TODO output your page here. You may use following sample code. */
out.println("<!DOCTYPE html>");
out.println("<html>");
out.println("<head>");
out.println("<title>Servlet AccountServlet</title>");
out.println("</head>");
out.println("<body>");
out.println("<h1>Servlet AccountServlet at " + request.getContextPath() + "</h1>");
out.println("</body>");
out.println("</html>");
}
}
// <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
/**
* Handles the HTTP <code>GET</code> method.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
#Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
//HttpSession session = request.getSession();
String action = request.getParameter("action");
if (action == null) {
request.getRequestDispatcher("/Welcome.jsp").forward(request, response);
} else if (action.equals("view")) {
Accounts acct = new Accounts();
ArrayList<Account> list = new ArrayList();
try {
acct.setCustAccounts(request.getParameter("id"));
list.addAll(acct.getCustAccounts());
System.out.println(request.getParameter("id"));
//This was moved into the try block itself
request.setAttribute("acctList", list);
request.getServletContext().getRequestDispatcher("/accounts.jsp").forward(request, response);
} catch (SQLException ex) {
Logger.getLogger(Accounts.class.getName()).log(Level.SEVERE, null, ex);
//This is the added finally statement with the clearAccounts method
} finally {
acct.clearAccounts();
}
}
}
/**
* Handles the HTTP <code>POST</code> method.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
#Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
String action = request.getParameter("action");
String custId = request.getParameter("custID");
if (action == null) {
request.getRequestDispatcher("/Welcome.jsp").forward(request, response);
}
}
/**
* Returns a short description of the servlet.
*
* #return a String containing servlet description
*/
#Override
public String getServletInfo() {
return "Short description";
}// </editor-fold>
}
The clear accounts method in the Accounts class was very very simple:
/**
* Clears the current array list of accounts
*/
public void clearAccounts(){
this.custAccounts.clear();
}

Related

Estado HTTP 500 – Internal Server Error, Netbeans ide 13 tomcat 8.5.78

I am doing a login with servlet but I get this error:
I don't know if it's a tomcat problem or why it will be but I already tried with netbeans 13 and netbeans 8.2 and jdk 18, jdk 8 and I still get the same error
The connection works correctly because I already checked it with a code
The mistake is:
Type: Status Report
Description: The requested resource is not available.
sometimes i get this too
exception
javax.servlet.ServletException: Error instantiating servlet class [controlador.Validar]
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:543)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:698)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:367)
org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:639)
org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)
org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:882)
org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1647)
org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191)
org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659)
org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
java.lang.Thread.run(Thread.java:750)
root cause
java.lang.ClassNotFoundException: controlador.Validar
org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1420)
org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1228)
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:543)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:698)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:367)
org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:639)
org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)
org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:882)
org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1647)
org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191)
org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659)
org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
java.lang.Thread.run(Thread.java:750)
note The full trace of the cause of this error is in the server log files.
index.jsp
<html lang="en">
<head>
<!-- Required meta tags -->
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
<!-- Bootstrap CSS -->
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css" integrity="sha384-JcKb8q3iqJ61gNV9KGb8thSsNjpSL0n8PARn9HuZOnIxN0hoP+VmmDGMN5t9UJ0Z" crossorigin="anonymous">
<title>Hello, world!</title>
</head>
<body>
<div class="container center-block" >
<div class="row justify-content-center">
<div class="card" style="width: 18rem;">
<img src="logo.png" class="card-img-top" alt="...">
<div class="card-body">
<form method="POST" action="Validar">
<div class="form-group">
<label>No de Documento</label>
<input type="text" class="form-control" name="txtusuario">
<small id="emailHelp" class="form-text text-muted">Ingrese su documento sin espacios ni puntos</small>
</div>
<div class="form-group">
<label for="exampleInputPassword1">Contraseña</label>
<input type="password" class="form-control" id="exampleInputPassword1" name="txtpassword">
</div>
<div class="form-group form-check">
<input type="checkbox" class="form-check-input" id="exampleCheck1">
<label class="form-check-label" for="exampleCheck1">Permanecer loggeado</label>
</div>
<button type="submit" class="btn btn-primary" name="accion" value="Ingresar">Ingresar</button>
</form>
</div>
</div>
</div>
</div>
<!-- Optional JavaScript -->
<!-- jQuery first, then Popper.js, then Bootstrap JS -->
<script src="https://code.jquery.com/jquery-3.5.1.slim.min.js" integrity="sha384-DfXdz2htPH0lsSSs5nCTpuj/zy4C+OGpamoFVy38MVBnE+IbbVYUew+OrCXaRkfj" crossorigin="anonymous"></script>
<script src="https://cdn.jsdelivr.net/npm/popper.js#1.16.1/dist/umd/popper.min.js" integrity="sha384-9/reFTGAW83EW2RDu2S0VKaIzap3H66lZH81PoYlFhbGU+6BZp6G7niu735Sk7lN" crossorigin="anonymous"></script>
<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/js/bootstrap.min.js" integrity="sha384-B4gt1jrGC7Jh4AgTPSdUtOBvfO8shuf57BaghqFfPlYxofvL8/KUEfYiJOMMV+rV" crossorigin="anonymous"></script>
</body>
</html>```
----------------------------------------------------------------------------
Controlador.java
/*
Servlet Controlador
*/
package Controlador;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
#WebServlet(name = "Controlador", urlPatterns = {"/Controlador"})
public class Controlador extends HttpServlet {
/**
* Processes requests for both HTTP <code>GET</code> and <code>POST</code>
* methods.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
String menu = request.getParameter("menu");
//Redirecciona a las paginas según la opción seleccionada agregando los casos respectivos
if(menu.equals("Principal")){
request.getRequestDispatcher("Principal.jsp").forward(request, response);
}
if(menu.equals("Productos")){
request.getRequestDispatcher("Productos.jsp").forward(request, response);
}
if(menu.equals("Empleados")){
request.getRequestDispatcher("Empleados.jsp").forward(request, response);
}
if(menu.equals("Clientes")){
request.getRequestDispatcher("Clientes.jsp").forward(request, response);
}
if(menu.equals("Ventas")){
request.getRequestDispatcher("Ventas.jsp").forward(request, response);
}
}
// <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
/**
* Handles the HTTP <code>GET</code> method.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
#Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
/**
* Handles the HTTP <code>POST</code> method.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
#Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
/**
* Returns a short description of the servlet.
*
* #return a String containing servlet description
*/
#Override
public String getServletInfo() {
return "Short description";
}// </editor-fold>
}
----------------------------------------------------------------------------
validar.java
/*
Servlet Validar
*/
package controlador;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.SQLException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import Modelo.Usuario;
import Modelo.UsuarioDAO;
#WebServlet(name = "Validar", urlPatterns = {"/Validar"})
public class Validar extends HttpServlet {
Usuario usuario = new Usuario();
UsuarioDAO usuarioDAO = new UsuarioDAO();
/**
* Processes requests for both HTTP <code>GET</code> and <code>POST</code>
* methods.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
try (PrintWriter out = response.getWriter()) {
/* TODO output your page here. You may use following sample code. */
out.println("<!DOCTYPE html>");
out.println("<html>");
out.println("<head>");
out.println("<title>Servlet Validar</title>");
out.println("</head>");
out.println("<body>");
out.println("<h1>Servlet Validar at " + request.getContextPath() + "</h1>");
out.println("</body>");
out.println("</html>");
}
}
// <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
/**
* Handles the HTTP <code>GET</code> method.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
#Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
/**
* Handles the HTTP <code>POST</code> method.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
#Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
String accion = request.getParameter("accion");
if (accion.equalsIgnoreCase("Ingresar")) {
int documento = Integer.parseInt(request.getParameter("txtusuario"));
String pass = request.getParameter("txtpassword");
try {
usuario = usuarioDAO.Validar(documento, pass);
} catch (SQLException ex) {
Logger.getLogger(Validar.class.getName()).log(Level.SEVERE, null, ex);
}
if (usuario.getNombre() != null) {
request.setAttribute("usuario", usuario);
request.getRequestDispatcher("Controlador?menu=Principal").forward(request, response);
} else {
request.getRequestDispatcher("index.jsp").forward(request, response);
}
} else {
request.getRequestDispatcher("index.jsp").forward(request, response);
}
}
/**
* Returns a short description of the servlet.
*
* #return a String containing servlet description
*/
#Override
public String getServletInfo() {
return "Short description";
}// </editor-fold>
}
----------------------------------------------------------------------------
usuario.java
package Modelo;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.logging.Level;
import java.util.logging.Logger;
public class Usuario {
int id;
int documento;
String nombre, correo, estado, password, rol;
public Usuario() {
}
public String getRol() {
return rol;
}
public void setRol(String rol) {
this.rol = rol;
}
public Usuario(int id, int documento, String nombre, String correo, String estado, String password, String rol) {
this.id = id;
this.documento = documento;
this.nombre = nombre;
this.correo = correo;
this.estado = estado;
this.password = password;
this.rol = rol;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public int getDocumento() {
return documento;
}
public void setDocumento(int documento) {
this.documento = documento;
}
public String getNombre() {
return nombre;
}
public void setNombre(String nombre) {
this.nombre = nombre;
}
public String getCorreo() {
return correo;
}
public void setCorreo(String correo) {
this.correo = correo;
}
public String getEstado() {
return estado;
}
public void setEstado(String estado) {
this.estado = estado;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
}
----------------------------------------------------------------------------
UsuarioDAO.java
package Modelo;
import Config.Conexion;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.logging.Level;
import java.util.logging.Logger;
public class UsuarioDAO {
Connection con;
PreparedStatement ps;
ResultSet rs;
Conexion cn = new Conexion();
public Usuario Validar(int documento, String password) throws SQLException {
Usuario usuario = new Usuario();
String consulta = "SELECT * FROM usuarios WHERE documento = ? AND password = ?";
con = cn.Conexion();
try {
ps = con.prepareStatement(consulta);
ps.setInt(1, documento);
ps.setString(2, password);
rs = ps.executeQuery();
rs.next();
do {
usuario.setId(rs.getInt("id"));
usuario.setDocumento(rs.getInt("documento"));
usuario.setNombre(rs.getString("nombre"));
usuario.setPassword(rs.getString("password"));
usuario.setCorreo(rs.getString("correo"));
usuario.setEstado(rs.getString("estado"));
usuario.setRol(rs.getString("rol"));
} while (rs.next());
} catch (SQLException ex) {
Logger.getLogger(UsuarioDAO.class.getName()).log(Level.SEVERE, null, ex);
}
return usuario;
}
}
`

Java Servlet And JSP problems

I am beginning to learn servlet . I had issue try to get url from a folder(outside my project) which contains many images but i don't know how to display them in jsp (GrassFish Server). i try with some code but it don't working correctly .Simply outputting to HTML does not seem to work.
I've not performed any manual servlet mapping and I haven't changed any of Tomcat's configuration files.
this is my servlet
import java.io.File;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
*
* #author tamgi
*/
public class getServlets extends HttpServlet {
/**
* Processes requests for both HTTP <code>GET</code> and <code>POST</code>
* methods.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
File file = new File("C:\\Users\\tamgi\\Downloads\\Source\\Kyou No Cerberus\\Chap_56");
File[] files = file.listFiles();
request.setAttribute("files", files);
request.getRequestDispatcher("Test.jsp").forward(request, response);
}
// <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
/**
* Handles the HTTP <code>GET</code> method.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
#Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
/**
* Handles the HTTP <code>POST</code> method.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
#Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
/**
* Returns a short description of the servlet.
*
* #return a String containing servlet description
*/
#Override
public String getServletInfo() {
return "Short description";
}// </editor-fold>
}
this is my jsp
<%#page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Page</title>
<% File[] files =(File[]) request.getAttribute("files"); %>
</head>
<body>
<br>
<% for(File f : files) { %>
<img src="<%= f.getCanonicalPath() %> " alt="empty">
<br>
<% } %>
</body>
</html>

java web Restful HTTP 404 Not Found

the java web client.
this is index.jsp
<%#page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Calcular factorial</title>
</head>
<body>
<div align="center">
<form action="calcular.do" style="font-family:arial">
Numero :<br>
<input type="text" name="base" style="text-align:right"/><br><br>
<input type="submit" value="calcular" name="Calcular" />
<br><br>
Resultado:<br>
<input type="text" name="resultado" value="${result}"
style="text-align:right"/><br><br>
</form>
</div>
</body>
</html>
this is the Calcular.java
package controlador;
import Webservicce.ClientRest;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
*
* #author x2010s
*/
#WebServlet(name = "Calcular", urlPatterns = {"/calcular.do"})
public class Calcular extends HttpServlet {
/**
* Processes requests for both HTTP <code>GET</code> and <code>POST</code>
* methods.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
ClientRest rest = new ClientRest();
String base = request.getParameter("base");
String factorial = rest.factorial(base);
request.setAttribute("factorial",factorial);
request.getRequestDispatcher("index.jsp").forward(request, response);
}
// <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
/**
* Handles the HTTP <code>GET</code> method.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
#Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
/**
* Handles the HTTP <code>POST</code> method.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
#Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
/**
* Returns a short description of the servlet.
*
* #return a String containing servlet description
*/
#Override
public String getServletInfo() {
return "Short description";
}// </editor-fold>
}
in the servlet, the factorial method must be called from the restful, to calculate the factorial with the entered number
this is the imported RESTful Java Client
package Webservicce;
import javax.ws.rs.ClientErrorException;
import javax.ws.rs.client.Client;
import javax.ws.rs.client.WebTarget;
public class ClientRest {
private WebTarget webTarget;
private Client client;
private static final String BASE_URI = "http://localhost:8080/SimpleRESTweb/webresources";
public ClientRest() {
client = javax.ws.rs.client.ClientBuilder.newClient();
webTarget = client.target(BASE_URI).path("factorial");
}
public String factorial(String base) throws ClientErrorException {
WebTarget resource = webTarget;
if (base != null) {
resource = resource.queryParam("base", base);
}
return resource.request().get(String.class);
}
public void close() {
client.close();
}
}
When I enter the number and click on calculate it appears
HTTP Status 500 - Internal Server Error
type Exception report
message Internal Server Error
description The server encountered an internal error that prevented it from fulfilling this request.
exception
javax.ws.rs.NotFoundException: HTTP 404 Not Found
errors appear in the java web client. I can not find the error, because it does not calculate the factorial

Connecting HTML with MSAcess in NetBeans

I have a HTML page where new users are added to the Database,I have done MS-Access connection through JDBC-ODBC and Servlets.I have no errors but the values aren't getting saved in the Database.
*******HTML FILE*****
<html>
<head>
<title>TODO supply a title</title>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
</head>
<body>
<div>
<center><h1>login page</h1></center>
<form action="Serve" method="get">
Username: <input type="text" name="username"><br>
Password: <input type="text" name="password"><br>
<button> Login</button>
</form>
</div>
</body>
</html>
***JDBC-ODBC FILE****
import java.sql.*;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.JOptionPane;
public class base {
Connection con;
Statement st;
ResultSet rs;
String s;
public base() throws SQLException {
connect();
}
private void connect() throws SQLException {
try {
// throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
con =DriverManager.getConnection("jdbc:odbc:db","","");
st=con.createStatement();
} catch (ClassNotFoundException ex) {
JOptionPane.showMessageDialog(null, ex);
}
}
}
*****SERVLETS***
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.SQLException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.swing.JOptionPane;
#WebServlet(name = "Serve", urlPatterns = {"/Serve"})
public class Serve extends HttpServlet {
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
try {
response.setContentType("text/html;charset=UTF-8");
PrintWriter out = response.getWriter();
base s = new base();
s.s="insert into Table1 values("+request.getParameter("name")+","+request.getParameter("pass")+")";
s.st.executeQuery(s.s);
} catch (SQLException ex) {
JOptionPane.showMessageDialog(null, ex);
}
}
// <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
/**
* Handles the HTTP <code>GET</code> method.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
#Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
/**
* Handles the HTTP <code>POST</code> method.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
#Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
/**
* Returns a short description of the servlet.
*
* #return a String containing servlet description
*/
#Override
public String getServletInfo() {
return "Short description";
}// </editor-fold>
}

The problem is that you get the wrong parameters from the request Object.
Try this:
s.s="insert into Table1 values("+request.getParameter("username")+","+request.getParameter("password")+")";

Java servlets resource not found

I am trying to enter a new user into my database with servlets.
I have a problem when I click submit button i registraion form. I get "The requested resource is not available." error. I cant figure it out.
Can you guys help me?
register.jsp
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Sign Up</title>
</head>
<body>
<h1>Enter your information</h1>
<form method = "POST" action="RegisterServlet">
Username <br/>
<input type="text" name="username"/><br/>
Password <br/>
<input type="password" name="password"/><br/>
Email <br/>
<input type="text" name="email"/><br/>
First name <br/>
<input type="text" name="fname"/><br/>
Last name <br/>
<input type="text" name="lname"/><br/>
<input type="submit" value="Confirm" />
</form>
</body>
RegisterServlet doPost() method
package servlet;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.*;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
#WebServlet(name = "RegisterServlet", urlPatterns = {"/RegisterServlet"})
public class RegisterServlet extends HttpServlet {
/**
* Processes requests for both HTTP <code>GET</code> and <code>POST</code>
* methods.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
}
// <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
/**
* Handles the HTTP <code>GET</code> method.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
#Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
}
/**
* Handles the HTTP <code>POST</code> method.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
#Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
PrintWriter out = response.getWriter();
String username = request.getParameter("username");
String password = request.getParameter("password");
String email = request.getParameter("email");
String fname = request.getParameter("fname");
String lname = request.getParameter("lname");
String admin = "no";
try {
Class.forName("com.mysql.jdbc.Driver").newInstance();
Connection con = DriverManager.getConnection("jdbc:mysql://localhost:3306/mobmelbaza", "root", "");
String query = "insert into korisnici(user, pass, email, ime, prezime, admin)"
+ "values ('" + username + "','" + password + "','" + email + "','" + fname + "','" + lname + "', '" + admin + "')";
Statement st = con.createStatement();
boolean done = st.execute(query);
if (done == true) {
out.print("Sign Up sucessfull");
} else {
out.print("Failed");
}
} catch (Exception ex) {
ex.printStackTrace();
}
}
/**
* Returns a short description of the servlet.
*
* #return a String containing servlet description
*/
#Override
public String getServletInfo() {
return "Short description";
}// </editor-fold>
}
web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="3.1" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd">
<servlet>
<servlet-name>RegisterServlet</servlet-name>
<servlet-class>servlet.RegisterServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>RegisterServlet</servlet-name>
<url-pattern>/RegisterServlet</url-pattern>
</servlet-mapping>
<session-config>
<session-timeout>
30
</session-timeout>
</session-config>
</web-app>

As you said you are using annotation better remove the mapping from the web.xml
You can either have annotation based mapping like
#WebServlet(name = "RegisterServlet", urlPatterns = {"/RegisterServlet"})
or
<servlet>
<servlet-name>RegisterServlet</servlet-name>
<servlet-class>servlet.RegisterServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>RegisterServlet</servlet-name>
<url-pattern>/RegisterServlet</url-pattern>
</servlet-mapping>
you cannot have both at once

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