Pantalla de Login

====== Ejercicio Login Tomcat ====== Nos basaremos en el siguiente diagrama para la implementación de la funcionalidad: {{:dad2:pasted:20240220-104411.png}} ===== Implementación Web ===== Implementamos el Front End de la aplicación en archivos .jsp: {{:dad2:pasted:20240220-105545.png}} ==== index.jsp ====


<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>




Pantalla de Login



	Login


  	Nombre:

  	Clave:

  	
  	Formulario de registro
<%
	String msg = (String) request.getAttribute("MSG");
	if (msg != null){
		out.println(msg);
	}

%>

==== insertar.jsp ====


<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>




Insert title here


	Registro
  	
  	Nombre:

  	Clave:

  	
  	Formulario de registro
  	
<%
	Hashtable usuarios = (Hashtable) request.getServletContext().getAttribute("TABLAUSUARIOS");
	
	if (usuarios != null){
		for(Usuario usuario : usuarios.values()){
			out.println("
" + usuario.getUsername());
		}
	}
		

%>

===== Implementación Java ===== ==== Usuario.java ====


package funciones;

public class Usuario {
	private String username;
	private String pass;
	public Usuario(String username, String pass) {
		super();
		this.username = username;
		this.pass = pass;
	}
	public String getUsername() {
		return username;
	}
	public void setUsername(String username) {
		this.username = username;
	}
	public String getPass() {
		return pass;
	}
	public void setPass(String pass) {
		this.pass = pass;
	}
}

===== Implementación Servlets ===== ==== login.java ====


package funciones;

import jakarta.servlet.ServletException;
import jakarta.servlet.annotation.WebServlet;
import jakarta.servlet.http.HttpServlet;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.Hashtable;



/**
 * Servlet implementation class Login
 */
public class Login extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public Login() {
        super();
        // TODO Auto-generated constructor stub
    }

	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		Hashtable usuarios = (Hashtable) request.getServletContext().getAttribute("TABLAUSUARIOS");		
		if(usuarios == null || usuarios.get(request.getParameter("paramUsername"))== null
				|| !(usuarios.get(request.getParameter("paramUsername"))).getPass().equals(request.getParameter("paramPass"))) {
			request.setAttribute("MSG", "Login incorrecto");
			request.getRequestDispatcher("index.jsp").forward(request, response);
		}else {
			
			request.getRequestDispatcher("insertar.jsp").forward(request, response);
		}
	}

	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		doGet(request, response);
	}

}

==== InsertarUsuario.java ====


package funciones;

import jakarta.servlet.ServletException;
import jakarta.servlet.annotation.WebServlet;
import jakarta.servlet.http.HttpServlet;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.Hashtable;

import jakarta.servlet.ServletConfig;

/**
 * Servlet implementation class InsertarUsuario
 */
public class InsertarUsuario extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public InsertarUsuario() {
        super();
        // TODO Auto-generated constructor stub
    }

    
	@Override
	public void init(ServletConfig config) throws ServletException {
		super.init(config);
		Hashtable usuarios = new Hashtable();
	    usuarios.put("admin", new Usuario("admin","admin"));
	        
		config.getServletContext().setAttribute("TABLAUSUARIOS",usuarios);
		
	}

    
    
	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		Hashtable usuarios = (Hashtable) request.getServletContext().getAttribute("TABLAUSUARIOS");		
		
		if(usuarios == null) {
			usuarios = new Hashtable();
			request.getServletContext().setAttribute("TABLAUSUARIOS",usuarios);
		}
		
		Usuario usuario = new Usuario(request.getParameter("paramUsername"), request.getParameter("paramPass"));
		usuarios.put(usuario.getUsername(), usuario);
		
		
		System.out.println("Usuarios en el sistema: " + usuarios.size());
		
		request.getRequestDispatcher("insertar.jsp").forward(request, response);
	}


	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		doGet(request, response);
	}

}