BAEL-1343 MVC Architecture with Servlets and JSP code (#3624)

* BAEL-1343 MVC Architecture with Servlets and JSP code

* BAEL-1343 code refactoring

* BAEL-1343 code refactoring

* BAEL-1343 updated code formatting

* BAEL-1343 code refactoring

javax-servlets/src/main/java/com/baeldung/controller/StudentServlet.java

@@ -0,0 +1,43 @@
+package com.baeldung.controller;
+
+import java.io.IOException;
+
+import javax.servlet.RequestDispatcher;
+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 com.baeldung.service.StudentService;
+
+/**
+ * 
+ * @author haseeb
+ *
+ */
+@WebServlet(name = "StudentServlet", urlPatterns = "/student-record")
+public class StudentServlet extends HttpServlet {
+
+    protected void processRequest(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
+        StudentService studentService = new StudentService();
+        String studentID = request.getParameter("id");
+        if (studentID != null) {
+            int id = Integer.parseInt(studentID);
+            request.setAttribute("studentRecord", studentService.getStudent(id));
+        }
+
+        RequestDispatcher dispatcher = request.getRequestDispatcher("/WEB-INF/jsp/student-record.jsp");
+        dispatcher.forward(request, response);
+    }
+
+    @Override
+    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
+        processRequest(request, response);
+    }
+
+    @Override
+    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
+        processRequest(request, response);
+    }
+}

javax-servlets/src/main/java/com/baeldung/model/Student.java

@@ -0,0 +1,62 @@
+package com.baeldung.model;
+
+/**
+ * 
+ * @author haseeb
+ *
+ */
+public class Student {
+
+    private int id;
+    private String firstName;
+    private String lastName;
+
+    public Student(int id, String firstName, String lastName) {
+        super();
+        this.id = id;
+        this.firstName = firstName;
+        this.lastName = lastName;
+    }
+
+    /**
+     * @return the id
+     */
+    public int getId() {
+        return id;
+    }
+
+    /**
+     * @param id the id to set
+     */
+    public void setId(int id) {
+        this.id = id;
+    }
+
+    /**
+     * @return the firstName
+     */
+    public String getFirstName() {
+        return firstName;
+    }
+
+    /**
+     * @param firstName the firstName to set
+     */
+    public void setFirstName(String firstName) {
+        this.firstName = firstName;
+    }
+
+    /**
+     * @return the lastName
+     */
+    public String getLastName() {
+        return lastName;
+    }
+
+    /**
+     * @param lastName the lastName to set
+     */
+    public void setLastName(String lastName) {
+        this.lastName = lastName;
+    }
+}

javax-servlets/src/main/java/com/baeldung/service/StudentService.java

@@ -0,0 +1,34 @@
+package com.baeldung.service;
+
+import com.baeldung.model.Student;
+
+/**
+ * 
+ * @author haseeb
+ *
+ */
+public class StudentService {
+
+    /**
+     * 
+     * @param id
+     * @return
+     */
+    public Student getStudent(int id) {
+
+        Student student = null;
+
+        switch (id) {
+        case 1:
+            student = new Student(1, "John", "Doe");
+            break;
+        case 2:
+            student = new Student(2, "Jane", "Goodall");
+            break;
+        case 3:
+            student = new Student(3, "Max", "Born");
+            break;
+        }
+        return student;
+    }
+}

javax-servlets/src/main/java/com/baeldung/servlets/FormServlet.java

@@ -25,7 +25,7 @@ public class FormServlet extends HttpServlet {
             response.setHeader("Test", "Success");
             response.setHeader("BMI", String.valueOf(bmi));
 
-            RequestDispatcher dispatcher = request.getRequestDispatcher("index.jsp");
+            RequestDispatcher dispatcher = request.getRequestDispatcher("/WEB-INF/jsp/index.jsp");
             dispatcher.forward(request, response);
         } catch (Exception e) {
 

javax-servlets/src/main/webapp/WEB-INF/jsp/student-record.jsp

@@ -0,0 +1,36 @@
+<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
+    pageEncoding="ISO-8859-1"%>
+
+<%@ page import="com.baeldung.model.Student"%>
+<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
+<html>
+<head>
+<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
+<title>Student Record</title>
+</head>
+<body>
+    <%
+        if (request.getAttribute("studentRecord") != null) {
+            Student student = (Student) request.getAttribute("studentRecord");
+    %>
+
+    <h1>Student Record</h1>
+    <div>
+        ID:
+        <%=student.getId()%></div>
+    <div>
+        First Name:
+        <%=student.getFirstName()%></div>
+    <div>
+        Last Name:
+        <%=student.getLastName()%></div>
+
+    <%
+        } else {
+    %>
+    <h1>No student record found.</h1>
+    <%
+        }
+    %>
+</body>
+</html>