MVC Pattern(1) - 첫 화면 띄우기

#1 MVC 구조

#2 ActionForward 클래스를 vo패키지에 추가한다.

package vo;   public class ActionForward { //1번     private String path; // 경로정보     private boolean redirect; // true:리다이렉트, false:디스패치          public ActionForward() {     }          public ActionForward(String path, boolean redirect) {         super();         this.path = path;         this.redirect = redirect;     }       public String getPath() {         return path;     }       public void setPath(String path) {         this.path = path;     }       public boolean isRedirect() {         return redirect;     }       public void setRedirect(boolean redirect) {         this.redirect = redirect;     } }

 

#3 action 패키지에 Action이라는 interface를 추가한다. 

package action;   import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse;   import vo.ActionForward;   public interface Action {     //2번     ActionForward execute(HttpServletRequest req, HttpServletResponse resp) throws Exception; }

 

#4 action패키지에 homeAction, 즉 첫 화면을 나타내는 Action을 추가한다.

package action;   import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse;   import vo.ActionForward;   public class HomeAction implements Action{       //3번     @Override     public ActionForward execute(HttpServletRequest req,HttpServletResponse resp)throws Exception {         ActionForward forward = new ActionForward();         forward.setPath("home");         forward.setRedirect(false);         return forward;     } }

#4 action패키지에 ActionFactory를 추가한다.

여기서 ActionFactory는 명령어에 따라 action을 담당하는 공장이 된다.

package action;   import java.util.HashMap; import java.util.Map;   public class ActionFactory { //4번      private static ActionFactory factory = new ActionFactory();          public static ActionFactory getInstance() {         return factory;     }          private Map<String,Action> map;          private ActionFactory() {         map = new HashMap<>();         map.put("home", new HomeAction());     }          public Action getAction(String command) {         return map.get(command);     } }

 

#5 FrontController , controller 패키지에 추가한다.

화면에 대한 controll을 담당하는 controller이다.

package 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 action.Action; import action.ActionFactory; import vo.ActionForward;   @WebServlet("*.do") public class FrontController extends HttpServlet{ // 5번     private static final long serialVersionUID = 1L;;       @Override     protected void doGet(HttpServletRequest req, HttpServletResponse resp)              throws ServletException, IOException {         // 명령Command 확인 및 주소만들기          String requestURI = req.getRequestURI();                  String contextPath = req.getContextPath();         String command = requestURI.substring(contextPath.length());                  int index = command.lastIndexOf(".");         command = command.substring(1,index);                  System.out.println("URI주소: " + requestURI);         System.out.println("contextPath: " + contextPath);         System.out.println("command: " + command);         System.out.println("명령어command: " + command);         // 주소로 이동          Action action = null;         ActionForward forward = null;         ActionFactory factory = ActionFactory.getInstance();                  action = factory.getAction(command);         if(action != null) {             try {                 forward = action.execute(req, resp);             } catch (Exception e) {                 e.printStackTrace();             }         }//if                  if(forward != null) {             if(forward.isRedirect()) {                 resp.sendRedirect(forward.getPath());             }else {                 String path ="WEB-INF/views/"+forward.getPath()+".jsp";                 RequestDispatcher dispathcher = req.getRequestDispatcher(path);                 dispathcher.forward(req, resp);             }         }//if               }       @Override     protected void doPost(HttpServletRequest req, HttpServletResponse resp)              throws ServletException, IOException {         req.setCharacterEncoding("utf-8");//한글처리         doGet(req,resp);     }           }

#6 index.jsp 

첫 화면의 리다이렉트를 담당한다.

<%@ page language="java" contentType="text/html; charset=UTF-8"     pageEncoding="UTF-8"%> <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %> <c:redirect url="home.do" />

 

#7 web.xml 

마찬가지로 첫 화면을 띄우기 위해 설정한다.

<?xml version="1.0" encoding="UTF-8"?> <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd" id="WebApp_ID" version="4.0">   <display-name>test</display-name>   <welcome-file-list>     <welcome-file>index.html</welcome-file>     <welcome-file>index.htm</welcome-file>     <welcome-file>index.jsp</welcome-file>     <welcome-file>default.html</welcome-file>     <welcome-file>default.htm</welcome-file>     <welcome-file>default.jsp</welcome-file>   </welcome-file-list> </web-app>