EJB

#Computer.java

/*
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 * and open the template in the editor.
 */
package bean;

import java.io.Serializable;

/**
 *
 * @author teacher
 */
public class Computer implements Serializable{
    String name, cpu, ram;

    public Computer() {
    }

    public Computer(String name, String cpu, String ram) {
        this.name = name;
        this.cpu = cpu;
        this.ram = ram;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getCpu() {
        return cpu;
    }

    public void setCpu(String cpu) {
        this.cpu = cpu;
    }

    public String getRam() {
        return ram;
    }

    public void setRam(String ram) {
        this.ram = ram;
    }

    @Override
    public String toString() {
        return "Computer{" + "name=" + name + ", cpu=" + cpu + ", ram=" + ram + '}';
    }
}

#ComputerSessionBean.java

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 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package session;

import bean.Computer;
import java.util.ArrayList;
import java.util.List;
import javax.ejb.Stateless;

/**
 *
 * @author teacher
 */
@Stateless
public class ComputerSessionBean implements ComputerSessionBeanLocal {
    List<Computer> computerList = new ArrayList<>();
    int index = 0;

    @Override
    public List<Computer> getComputerList() {
        return computerList;
    }

    @Override
    public void add(Computer computer) {
        computerList.add(computer);
    }

    @Override
    public Computer get(int index) {
        return computerList.get(index);
    }

    // Add business logic below. (Right-click in editor and choose
    // "Insert Code > Add Business Method")

    @Override
    public void fakeData() {
        index++;
        computerList.add(new Computer("A1 >> " + index, "Core I7", "8 GB"));
        computerList.add(new Computer("A2 >> " + index, "Core I7", "8 GB"));
        computerList.add(new Computer("A3 >> " + index, "Core I7", "8 GB"));
        computerList.add(new Computer("A4 >> " + index, "Core I7", "8 GB"));
        computerList.add(new Computer("A5 >> " + index, "Core I7", "8 GB"));
        computerList.add(new Computer("A6 >> " + index, "Core I7", "8 GB"));
        computerList.add(new Computer("A7 >> " + index, "Core I7", "8 GB"));
    }
}

#ComputerSessionBeanLocal.java

/*
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 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package session;

import bean.Computer;
import java.util.List;
import javax.ejb.Local;

/**
 *
 * @author teacher
 */
@Local
public interface ComputerSessionBeanLocal {
    List<Computer> getComputerList();
    void add(Computer computer);
    Computer get(int index);
    void fakeData();
}

#CounterSessionBean.java

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package session;

import javax.ejb.Stateful;

/**
 *
 * @author teacher
 */
@Stateful
public class CounterSessionBean implements CounterSessionBeanLocal {
    int count = 0;

    @Override
    public int getCount() {
        return ++count;
    }

    // Add business logic below. (Right-click in editor and choose
    // "Insert Code > Add Business Method")
}

#CounterSessionBeanLocal.java

/*
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 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package session;

import javax.ejb.Local;

/**
 *
 * @author teacher
 */
@Local
public interface CounterSessionBeanLocal {
    int getCount();
}

#index.jsp

<%-- 
    Document   : index
    Created on : Jan 9, 2021, 9:22:12 AM
    Author     : teacher
--%>

<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%@page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
	<title>Computer List</title>
	<!-- Latest compiled and minified CSS -->
	<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.4.1/css/bootstrap.min.css"/>

	<!-- jQuery library -->
	<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.4.1/jquery.min.js"></script>

	<!-- Popper JS -->
	<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.16.0/umd/popper.min.js"></script>

	<!-- Latest compiled JavaScript -->
	<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.4.1/js/bootstrap.min.js"></script>
</head>
<body>
	<div class="container">
		<div class="panel panel-primary">
			<div class="panel-heading">
				<h2 class="text-center">Computer List</h2>
			</div>
			<div class="panel-body">
                            <table class="table table-bordered">
                                <thead>
                                    <tr>
                                        <th>STT</th>
                                        <th>Ten</th>
                                        <th>CPU</th>
                                        <th>RAM</th>
                                    </tr>
                                </thead>
                                <tbody>
                                    <c:forEach items="${computerList}" var="item" varStatus="loop">
                                        <tr>
                                            <td>${loop.index + 1}</td>
                                            <td>${item.name}</td>
                                            <td>${item.cpu}</td>
                                            <td>${item.ram}</td>
                                        </tr>
                                    </c:forEach>
                                </tbody>
                            </table>
                            <a href="fake.html"><button class="btn btn-danger">Fake Data</button></a>
			</div>
		</div>
	</div>
</body>
</html>

#index.jsp

<%-- 
    Document   : index
    Created on : Jan 9, 2021, 9:04:46 AM
    Author     : teacher
--%>

<%@page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
    <head>
        <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
        <title>JSP Page</title>
    </head>
    <body>
        <h1>Counter: ${count}!</h1>
    </body>
</html>

#ComputerController.java

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package aptech.controller;

import bean.Computer;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import org.springframework.stereotype.Controller;
import org.springframework.ui.ModelMap;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import session.ComputerSessionBeanLocal;

/**
 *
 * @author teacher
 */
@Controller
@RequestMapping(value = "/computer")
public class ComputerController {
    ComputerSessionBeanLocal computerSessionBean = lookupComputerSessionBeanLocal();
    
    
    @RequestMapping(value = "/index", method = RequestMethod.GET)
    public String index(ModelMap modelMap) {
        List<Computer> computerList = computerSessionBean.getComputerList();
        
        modelMap.put("computerList", computerList);
        
        return "/computer/index";
    }
    
    
    @RequestMapping(value = "/fake", method = RequestMethod.GET)
    public String fake(ModelMap modelMap) {
       computerSessionBean.fakeData();
        
        return "redirect:index.html";
    }

    private ComputerSessionBeanLocal lookupComputerSessionBeanLocal() {
        try {
            Context c = new InitialContext();
            return (ComputerSessionBeanLocal) c.lookup("java:global/EJBExample01/EJBExample01-ejb/ComputerSessionBean!session.ComputerSessionBeanLocal");
        } catch (NamingException ne) {
            Logger.getLogger(getClass().getName()).log(Level.SEVERE, "exception caught", ne);
            throw new RuntimeException(ne);
        }
    }
}

#CounterController.java

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package aptech.controller;

import java.util.logging.Level;
import java.util.logging.Logger;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import org.springframework.stereotype.Controller;
import org.springframework.ui.ModelMap;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import session.CounterSessionBeanLocal;

/**
 *
 * @author teacher
 */
@Controller
@RequestMapping(value = "/counter")
public class CounterController {
    CounterSessionBeanLocal counterSessionBean = lookupCounterSessionBeanLocal();
    
    
    @RequestMapping(value = "/index", method = RequestMethod.GET)
    public String index(ModelMap modelMap) {
        int count = counterSessionBean.getCount();
        
        modelMap.put("count", count);
        
        return "/counter/index";
    }
    
    
    @RequestMapping(value = "/test", method = RequestMethod.GET)
    public String test(ModelMap modelMap) {
        int count = counterSessionBean.getCount();
        
        modelMap.put("count", count);
        
        return "/counter/index";
    }

    private CounterSessionBeanLocal lookupCounterSessionBeanLocal() {
        try {
            Context c = new InitialContext();
            return (CounterSessionBeanLocal) c.lookup("java:global/EJBExample01/EJBExample01-ejb/CounterSessionBean!session.CounterSessionBeanLocal");
        } catch (NamingException ne) {
            Logger.getLogger(getClass().getName()).log(Level.SEVERE, "exception caught", ne);
            throw new RuntimeException(ne);
        }
    }
}