[Day9] JSP/Servlet 9 - MVC 패턴, filter

[Day9] JSP/Servlet 9 [12/14]

[ p 516 Chapter 18 MVC 패턴 구현 ]

- 모델 1 구조 / 모델 2구조

- MVC 패턴

- 커맨드 패턴을 사용한 [컨트롤러(Controller)] 구현 ( MVC 패턴의 핵심 )

모델 2구조 기반의 MVC 패턴으로 웹 어플리케이션 구현하는 것이 목적.

- JSP 개발자라면 "반드시 습득해야할 기술"이다.

- Spring(MVC 패턴 프레임워크)에 보다 쉽게 적응할 수 있다.

[ JSP 웹 어플리케이션의 구조 ]

  1) 모델 1구조

  [클] -> 요청-> [JSP페이지]
  로직담당
  출력담당
     <-응답<-

2) 모델 2구조

  [클] -> 요청-> [JSP페이지]  + [객체]
  출력담당   로직담당
     <-응답<-

예)

list.htm -> List.java 서블릿 -> list.jsp

doGet(){

// 로직처리 // 출력담당

request.setAttribute();

// 포워딩

}

[MVC 패턴] 로직 + 출력 담당 구분( 모델2구조 )

M Model - 로직 처리 담당, 비즈니스 영역 , 서블릿 X, 자바 클래스 (객체)

V View - 출력 담당, 프레젠테이션 영역 , list.jsp

C 컨트롤러 ***** - 사용자의 입력처리와 흐름 제어 담당. 서블릿 1개

Model

[list.htm] ListHandler.java - list = 서비스 - DAO ( list = select() )

edit.htm EditHander.java

view.htm -> 컨트롤러(서블릿) list

delete.htm 1) 요청URL 분석 request.setAttribute("")

write.htm list.htm(게시글 목록 ) list.jsp

: :

식당

손님 + 주문(홀서빙)-> 컨트롤러 -> 주방(요리사) + 음식 준비

<- <- 컨트롤러 <-

- 웹 개발자라면 반드시 알아야 할 패턴이다.

[ MVC 패턴의 핵심 ]

1. 로직 + 출력 담당 분리

2. 컨트롤러 역할 중요(집중)

개발 기간은 훨씬 많이 걸리지만 유지,보수, 확장성이 뛰어나기에~~

p 520 그림 18.4 MV[C] 컨트롤러의 역할 ( 암기 ) 시험...

1.[클] -> 모든 요청 -> 컨트롤러(C)[서블릿]

list.htm 1) 요청URL 분석

http://~~~/list.htm?cp=2&sc=1&sw=aaa

글 목록

2) 많은 로직 담당은 핸들러(Handler) - 모델

글 목록 핸들러 객체를 얻어온다(찾는다.)

3) 글목록핸들러.로직처리();

list= 서비스 - list = DAO - DB 연동

request.setAttribute();

list.jsp

4) 포워딩 또는 리다이렉트

<-응답- 뷰( jsp )

[ p 528 커맨드 패턴 기반의 코드 ]

[요청 URL 분석 + 명령어 전달] 2가지

http://localhost/jspPro/cstvsboard/delete.htm?seq=340

delete.htm : 게시글 삭제 -> Delete.java 서블릿

?seq=340 : 340 글번호 삭제

1) 특정 이름의 파라미터에 명령어 정보를 전달

http://localhost/jspPro/cstvsboard/board.htm?cmd=delete&seq=340

http://localhost/jspPro/cstvsboard/board.htm?cmd=list

http://localhost/jspPro/cstvsboard/board.htm?cmd=edit

2) 요청 URI 자체를 명령어로 사용한다.

http://localhost/jspPro/cstvsboard/delete.htm?seq=340

http://localhost/jspPro/cstvsboard/delete/340

http://localhost/jspPro/cstvsboard/edit.htm?seq=340

p 531 설명

CommandHandler 인터페이스 + String process()

"???.jsp"

로직 담당 클래스

List[Handler] process(){}

WriteForm[Hanlder] process(){}

: process(){}

p 533 컨트롤러(서블릿) 구현 예제

p 536 web.xml 컨트롤러 등록 코딩.

p 537 commandHandler.properties 파일

요청URL=모델(핸들러)

hello=mv.hello. HelloHandler

hello=mv.hello.HelloHandler

   [ 게시판 구현 ]
   days05
     ㄴ board 폴더
     ㄴ delete.jsp
     ㄴ edit.jsp
     ㄴ list.jsp
     ㄴ view.jsp
     ㄴ write.jsp

  days05.board
  ㄴ BoardDTO.java
  ㄴ BoardDAO.java
  ㄴ BoardDAOImpl.java
  ㄴ Delete.java (서블릿)
  ㄴ Edit.java   (서블릿)
  ㄴ List.java     (서블릿)
  ㄴ View.java   (서블릿)
  ㄴ Write.java   (서블릿)
  ㄴ PageBlock.java - 페이징 처리 만든 클래스

  [ 위에 게시판 구현을 MVC 패턴으로 구현(처리) ]
  1. days09 폴더
     ㄴ board 폴더 생성
  출력담당 View
  2.   days09>board 폴더 안에  출력담당 jsp 파일 모두 복사 붙이기.
  3.   MV[C] 컨트롤러  서블릿 선언
  web.xml  컨트롤러 서블릿 등록
  1) web.xml 복사 붙이기 + web_days08.xml
  DBCP 커넥션 풀 설정 부분만 남겨둔다. 그외는 모두 삭제.
  4. 컨트롤러  서블릿 클래스 추가.
     Spring 프레임워크의 컨트롤러 이름이 DispatcherServlet 과 동일하게 명명.
     days09.mvc.controller.DispatcherServlet.java 서블릿

     5. 컨트롤러를 web.xml 서블릿 등록.

     6. 인터페이스, 핸들러,   검색 목록페이지( 요청URL=핸들러 매핑)
  days09.mvc.command 패키지
  //   1) CommandHandler 인터페이스 + process()
//   2) ListHandler, WriteHandler 모델.

//   3) /WEB-INF/commandHandler.properties

  7. days09.mvc.controller.DispatcherServlet.java 서블릿  객체 언제 생성이 되나?
  ㄴ 첫 번째 요청이 들어오면 그 때 서블릿 객체는 [ 웹 컨테이너 ] 안에 생성되어진다.

  => 톰캣 서버가 시작될 때 자동으로 컨트롤러(서블릿) 객체를 미리 생성해 두면..  성능 향상
  web.xml 코딩 추가
  <load-on-startup>1</load-on-startup>

  8.   컨트롤러가 서버 시작할때 자동으로 서블릿 객체 생성이 된다...
     ㄴ 서블릿 객체 가 생성될 때 초기화작업 좀 할게요... (option command s -> override)

     init() 메서드 구현

  9.  서버 재시작 - 오류 발생
  java.lang.ClassNotFoundException: days09.mvc.command.WriteHandler

  10.  DispatcherServlet
     ㄴ  doGet() 코딩 마무리...


  11.   글 목록 MVC 패턴으로 구현 완료!!!

web.xml

<?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_3_1.xsd" id="WebApp_ID" version="3.1">
  <display-name>jspPro</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>
     
     <!-- DBCP 설정 -->
     <resource-ref>
		 <description>Oracle Datasource example</description>
		 <res-ref-name>jdbc/myoracle</res-ref-name>
		 <res-type>javax.sql.DataSource</res-type>
		 <res-auth>Container</res-auth>
	</resource-ref>
	
	
	<!-- 
	@WebFilter(dispatcherTypes = {DispatcherType.REQUEST }
					, urlPatterns = { "/*" })
	 -->				
	<filter>
	  <filter-name>characterEncodingFilter</filter-name>
	  <filter-class>com.filter.CharacterEncodingFilter</filter-class>
	</filter>
	<filter-mapping>
	  <filter-name>characterEncodingFilter</filter-name>
	  <url-pattern>/*</url-pattern> 
	  <!-- <url-pattern>/</url-pattern>  위의 패턴과 차이점. -->
	  <dispatcher>REQUEST</dispatcher>
	</filter-mapping>
	
	
</web-app>

days09 - mvc - controller폴더 안에

DispatcherServlet.java

package days09.mvc.controller;

import java.io.FileReader;
import java.io.IOException;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Properties;
import java.util.Set;

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 days09.mvc.command.CommandHandler;
 
public class DispatcherServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;
      
    public DispatcherServlet() {
        super(); 
        // 초기화 작업 
    }
     
	@Override
	public void destroy() { 
		super.destroy();
	}
 
	// key = "/board/list.do" 요청URL
	// value = "days09.mvc.command.ListHandler"  X   생성된 핸들러 객체 생성 
	private Map<String, CommandHandler>  commandHandlerMap = new HashMap<String, CommandHandler>();
	
	@Override
	public void init() throws ServletException {
		// 초기화 작업.
		// 1.         /WEB-INF/commandHandler.properties      
		String path = this.getInitParameter("path");
		String realPath = this.getServletContext().getRealPath(path);
		
		Properties prop = new Properties();		
		try(FileReader reader = new FileReader(realPath) ) {
			prop.load(reader);
		} catch (Exception e) {
			 throw new ServletException();
		}
		
		// commandHandlerMap<url, 실제 핸들러 객체 생성>
		Set<Entry<Object, Object>> set =  prop.entrySet();
		Iterator<Entry<Object, Object>> ir = set.iterator();
		while( ir.hasNext()) {
			Entry<Object, Object> entry = ir.next();
			String url = (String) entry.getKey();    // "/board/list.do" 
			String className = (String) entry.getValue();                    //  "days09.mvc.command.ListHandler"
			
			try {
				Class<?> handlerClass = Class.forName(className);
				CommandHandler  commandHandler = (CommandHandler) handlerClass.newInstance();				
				commandHandlerMap.put(url, commandHandler);
			} catch (ClassNotFoundException | InstantiationException | IllegalAccessException e) { 
				e.printStackTrace();
			}
			
		} // while
		
	}  // init

	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// System.out.println("> DispatcherServlet.doGet() 호출됨...");
		// [ 1 요청 URL 분석 ]
		//    [/board/list.do], edit.do, [/board/write.do] ~~   ???.do
		String requestURI =  request.getRequestURI();  //          "/jspPro/board/list.do"
		// String requestURL = request.getRequestURL().toString();  // http://localhost/jspPro/board/list.do
		
		//System.out.println(requestURI);
		//System.out.println(requestURL);
		
		//  requestURI 경로 에서 컨텍스트패스만 제거하면       commandHandlerMap  key =       "/board/list.do"
		String contextPath = request.getContextPath();   //   "/jspPro"
		
		if (   requestURI.indexOf(contextPath)  == 0 ) {
			int beginIndex = contextPath.length();
			requestURI = requestURI.substring(beginIndex);
		}
		
		// [ 2 로직 처리 - 핸들러 검색 ]
		//    1) CommandHandler 인터페이스 + process()
		//    2) [WriteHandler], WriteHandler 모델. 
		//    3) commandHandler.properties                 -> Properties 컬렉션 클래스 
		
		//    "/board/write.do"  요청URL 없는 핸들러 객체 : p536 NullHandler 클래스 선언
		CommandHandler handler = commandHandlerMap.get(requestURI);
 
		
		// 3 String viewpage =핸들러.process();     		
		String viewPage = null;
		try {
			viewPage = handler.process(request, response);
		} catch (Exception e) {
			e.printStackTrace();
		}
		
		// 4 포워딩, 리다렉트 체크
		// request.ㅎetAttribute("포리");
		// if( 1 ) 포워딩
		// else if( 2) 리다이렉트
		
		// (정의)  포워딩.
		if( viewPage != null ) {
			RequestDispatcher dispatcher = request.getRequestDispatcher(viewPage);
			dispatcher.forward(request, response);
		}
		
	}
 
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		doGet(request, response);
	}

}

- 요청별로 핸들러

jsp

 <a href="<%= contextPath %>/board/list.do">글목록</a><br>
 <a href="<%= contextPath %>/board/write.do">글쓰기</a><br>

- do 확장자 서블릿 요청하도록

Handler

days09 - mvc - command폴더 안에

CommandHandler.java (인터페이스)

package days09.mvc.command;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public interface CommandHandler {
	
	// 리턴자료형   :  포워딩, 리다이렉트   뷰페이지( ???.jsp )
	public String process(HttpServletRequest request, HttpServletResponse response) throws Exception;
    
}

- 컨트롤러로부터 request 매개변수로 받아와서 서블릿(컨트롤러) 에서 사용할수있는 request에다가 setAttribute할수 있도록 매개변수로 받음.

- 예외발생하면 호출한 곳으로 떠넘기는식으로

ListHandler.java

package days09.mvc.command;

import java.sql.Connection;
import java.sql.SQLException;
import java.util.ArrayList;

import javax.servlet.RequestDispatcher;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.util.ConnectionProvider;
import com.util.DBConn;

import days05.board.BoardDAOImpl;
import days05.board.BoardDTO;
import days05.board.PageBlock;

// list.do 요청에 로직 담당 핸들러
public class ListHandler implements CommandHandler{

	@Override
	public String process(HttpServletRequest request, HttpServletResponse response) throws Exception {
		// days05.board.List.java 서블릿
		int currentPage = 1 ;                
		try {  currentPage=Integer.parseInt(request.getParameter("currentpage")) ;}catch(Exception e) {}
		int numberPerPage = 10;          
		int numberOfPageBlock = 10;   
 
		int searchCondition = 1;
		try {  searchCondition=Integer.parseInt(request.getParameter("searchCondition")) ;}catch(Exception e) {}				
		String searchWord =  request.getParameter("searchWord") == null ? "" :  request.getParameter("searchWord");
		ArrayList<BoardDTO> list = null;
		
		int totalRecords, totalPages  = 0;

		Connection conn =  ConnectionProvider.getConnection();
		BoardDAOImpl dao = new BoardDAOImpl(conn);
		PageBlock pageBlock = null;

		try { 
			if( searchWord == "" ) {
				list = dao.select(currentPage, numberPerPage);
			}else {
				list = dao.search(currentPage, numberPerPage, searchCondition, searchWord);
			} 
			pageBlock = pagingService(currentPage,  numberPerPage,  numberOfPageBlock , dao
					, searchCondition, searchWord );

		} catch (SQLException e) {
			System.out.println("> ListHandler.process() Exception...");
			e.printStackTrace();
		}		
		conn.close();   // 커넥션 풀 반환

		request.setAttribute("list", list);
		request.setAttribute("pageBlock", pageBlock)  ;  
		
		// 포 1,  리  2
		// request.setAttribute("포리", 1);

		return  "/days09/board/list.jsp"; 
		
		// Modal.java 클래스 선언 viewPage , 포+리
		// return new Modal( viewPage, 1);
		
		// 리다이렉트 바로 시킬게요..
	} // process

	public PageBlock  pagingService(int currentPage, int numberPerPage, int numberOfPageBlock, BoardDAOImpl dao
			, int searchCondition, String searchWord ) {
		PageBlock pageBlock = null;
		int totalRecords =0;		
		int totalPages   = 1; 
		try { 
			if( searchWord == "" ) {
				totalRecords = dao.getTotalRecords()  ;		                   		
				totalPages    =   dao.getTotalPages( numberPerPage )  ;
			}else {
				totalRecords = dao.getTotalRecords(searchCondition, searchWord); 	 
				totalPages    =   dao.getTotalPages( numberPerPage,searchCondition, searchWord )  ; 
			} 
			int begin = ( currentPage - 1)/numberOfPageBlock * numberOfPageBlock + 1;
			int end    = begin + numberOfPageBlock - 1;
			if( end > totalPages )  end = totalPages;
			boolean prev =   begin == 1 ?  false : true;
			boolean next  =  end == totalPages ? false: true;
			pageBlock = new PageBlock(currentPage, numberPerPage, numberOfPageBlock ,begin, end, prev,  next);

		} catch( SQLException e) {
			e.printStackTrace();
		}
		return pageBlock;
	}

} // class

- 컨트롤러가 해당 핸들러 부르면 핸들러가 db 작업하고 매개변수로 받은 request객체에 담아서 return해주는 역할

- 컨트롤러에서 url 분석해서 listhandler 호출 (commandHandler.properties -> 얘를 기준으로 검색, Properties 컬렉션 클래스임)

<%@ page  trimDirectiveWhitespaces="true"%>
<%@ page contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<%@ taglib prefix="c"  uri="http://java.sun.com/jsp/jstl/core" %>
<%@ include file="/WEB-INF/inc/include.jspf"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>2022. 12. 8. 오후 4:45:18</title>
<link rel="shortcut icon" type="image/x-icon" href="../images/SiSt.ico">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.6.1/jquery.min.js"></script>
<style>
table, td, th {
	border: solid 1px gray;
}

table {
	border-spacing: 3px;
	border-collapse: separate;
}

table, tr, td {
	/* border-radius: 3px; */
	/* padding:3px;  */
	
}

tbody tr  td:nth-of-type(2) {
	text-align: left;
}

a {
	text-decoration: none;
	color: black;
}

a:hover {
	color: red;
}
</style>
<!-- 페이징 처리 style -->
<style>
.pagination {
	margin: 0 auto;
	display: flex;
	justify-content: center;
}

.pagination a {
	color: black;
	float: left;
	padding: 4px 8px;
	text-decoration: none;
	transition: background-color .3s;
}

.pagination a.active {
	background-color: dodgerblue;
	color: white;
}

.pagination a:hover:not (.active ) {
	background-color: #ddd;
}
</style>
<style>
.searchWord {
	background-color: yellow;
	color: red;
}
</style>
<style>
.title {
	display: inline-block;
	white-space: nowrap;
	width: 90%;
	overflow: hidden;
	text-overflow: ellipsis;
}
</style>
</head>
<body>
<h3>list.jsp</h3>

<div align="center">
  <h2>목록 보기</h2>
  <a href="<%= contextPath %>/board/write.do">글쓰기</a>
  <table style="width:600px;">
    <thead>
	    <tr>
	        <th width="10%">번호</th>
	        <th width="45%">제목</th>
	        <th width="17%">작성자</th>
	        <th width="20%">등록일</th>
	        <th width="10%">조회</th>
	      </tr>
    </thead>
    <tbody>
       <c:choose>
          <c:when test="${ not empty list }">
          
              <c:forEach items="${ list }" var="dto">
                 <tr>
                   <td>${ dto.seq }</td>
                   <%-- <td><a href="<%= contextPath %>/cstvsboard/view.htm?seq=${ dto.seq }">${dto.title }</a></td> --%>
                   <td><a href="<%= contextPath %>/board/view.do?seq=${ dto.seq }&currentpage=${ param.currentpage}&searchCondition=${ param.searchCondition}&searchWord=${ param.searchWord}">${dto.title }</a></td>
                   <td><a href="mailto:${ dto.email }">${ dto.writer }</a></td>
                   <td>${ dto.writedate }</td>
                   <td>${ dto.readed }</td>
                 </tr>
              </c:forEach>
          
          </c:when>
          <c:otherwise>
             <tr>
              <td colspan="5">등록된 게시글이 없습니다.</td>
             </tr>
          </c:otherwise>
       </c:choose>
    </tbody>
    <tfoot>
      <tr>
        <td colspan="5" align="center">
          <div class="pagination">  
          <%-- 
            <a href="#" class="active"> 1 </a> 
            <a href="<%= contextPath %>/cstvsboard/list.htm?currentpage=2"> 2 </a> 
            <a href="<%= contextPath %>/cstvsboard/list.htm?currentpage=3"> 3 </a> 
            <a href="<%= contextPath %>/cstvsboard/list.htm?currentpage=4"> 4 </a> 
            <a href="<%= contextPath %>/cstvsboard/list.htm?currentpage=5"> 5 </a> 
            <a href="<%= contextPath %>/cstvsboard/list.htm?currentpage=6"> 6 </a> 
            <a href="<%= contextPath %>/cstvsboard/list.htm?currentpage=7"> 7 </a> 
            <a href="<%= contextPath %>/cstvsboard/list.htm?currentpage=8"> 8 </a> 
            <a href="<%= contextPath %>/cstvsboard/list.htm?currentpage=9"> 9 </a> 
            <a href="<%= contextPath %>/cstvsboard/list.htm?currentpage=10"> 10 </a> 
            <a href="<%= contextPath %>/cstvsboard/list.htm?currentpage=11"> &raquo; </a>
             --%>  
     
             <c:if test="${ pageBlock.prev }">
                  <a href="<%= contextPath %>/cstvsboard/list.htm?currentpage=${  pageBlock.startOfPageBlock - 1  }"> &laquo; </a>
             </c:if>
             <c:forEach begin="${  pageBlock.startOfPageBlock  }" end="${  pageBlock.endOfPageBlock  }" var="i" step="1">
                 <c:choose> 
                    <c:when test="${ pageBlock.currentPage eq i }">
                       <a href="#" class="active">${ i }</a> 
                    </c:when>
                    <c:otherwise>
                       <a href="<%= contextPath %>/cstvsboard/list.htm?currentpage=${ i }">${ i }</a> 
                    </c:otherwise>
                 </c:choose>
             </c:forEach>
             <c:if test="${ pageBlock.next }">
                  <a href="<%= contextPath %>/cstvsboard/list.htm?currentpage=${  pageBlock.endOfPageBlock + 1  }"> &raquo; </a>
             </c:if>
             
          </div>
        </td>
      </tr>
      <tr>
        <td colspan="5" align="center">
          <form method="get">
             <select name="searchCondition" id="searchCondition">
              <option value="1">title</option>
              <option value="2">content</option>
              <option value="3">writer</option>
              <option value="4">title+content</option>
            </select>
            <input type="text" name="searchWord" id="searchWord" />
            <input type="submit" value="search" />
          </form>
        </td>
      </tr>
    </tfoot>
  </table>
</div>


<script>
   // list.htm?searchCondition=3&searchWord=검색어
	// list.htm
   $(function (){
	   
	   // list.htm?write=success
	   if(  '<%=  request.getParameter("write") %>'  == 'success' ){
		   alert("글 쓰기 완료!!!")
	   }
	   
	    // list.htm?delete=success
	   if(  '${ param.delete}'  == 'success' ){
		   alert("글 삭제 완료!!!")
	   }
	   
	   
	   // 검색 상태 관리
	   $("#searchCondition").val(   '${  empty param.searchCondition? 1 :  param.searchCondition }'        );
	   $("#searchWord").val( '${ param.searchWord}' );	   
	   
	    //   /jspPro/cstvsboard/list.htm?currentpage=2           + &searchCondition=1&searchWord=title+-+30
	   $(".pagination a:not(.active)").attr("href" , function (i,val){
		   return val + "&searchCondition=${ param.searchCondition}&searchWord=${ param.searchWord}";
	   });
   });
</script>
</body>
</html>

WEB-INF에 (외부접근못하게) commandHandler.properties 생성

# /jspPro  X  request URL=Handler 
/board/list.do=days09.mvc.command.ListHandler
/board/write.do=days09.mvc.command.WriteHandler
/board/view.do=days09.mvc.command.ViewHandler
/board/edit.do=days09.mvc.command.EditHandler
/board/delete.do=days09.mvc.command.DeleteHandler

컨트롤러에서 서블릿 초기화

(생성자, init 어디서해도 상관없음)

writeHandler.java

package days09.mvc.command;

import java.sql.Connection;
import java.sql.SQLException;

import javax.servlet.RequestDispatcher;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.util.ConnectionProvider;
import com.util.DBConn;

import days05.board.BoardDAOImpl;
import days05.board.BoardDTO;

public class WriteHandler implements CommandHandler{

	@Override
	public String process(HttpServletRequest request, HttpServletResponse response) throws Exception {
		
		String requestMethod = request.getMethod();  // "GET"         "POST"
		if(requestMethod.equals("GET")) {   // "GET"       Write.java  doGet() 복사 붙이기
			 // 포워딩 
			return  "/days09/board/write.jsp";
			
		}else if(requestMethod.equals("POST")) {  // "POST"       Write.java  doPost() 복사 붙이기
			 // 리다이렉트 
			request.setCharacterEncoding("UTF-8"); 
			String writer = request.getParameter("writer") ;
			String pwd = request.getParameter("pwd") ;
			String email = request.getParameter("email") ;
			String title = request.getParameter("title") ;
			String content  = request.getParameter("content") ;
			int tag = Integer.parseInt(  request.getParameter("tag") );
			
			BoardDTO dto = new BoardDTO(0, writer, pwd, email, title, null, 0, tag, content);
			
			Connection conn = ConnectionProvider.getConnection();
			BoardDAOImpl dao = new BoardDAOImpl(conn);
			int rowCount = 0;
			try {
				rowCount = dao.insert(dto);
			} catch (SQLException e) {
				System.out.println("> WriteHandler.process() Exception...");
				e.printStackTrace();
			}
			conn.close(); // 커넥션 풀 반환.
			
			String location = "/jspPro/board/list.do";
			if( rowCount == 1) {
				location +="?write=success";
			}else {
				location +="?write=fail";
			}
			response.sendRedirect(location);
		} // 
		
		return null;
	}

}

write.jsp

<%@ page contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<%@ taglib prefix="c"  uri="http://java.sun.com/jsp/jstl/core" %>
<%@ include file="/WEB-INF/inc/include.jspf"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>2022. 12. 8. 오후 3:28:25</title>
<link rel="shortcut icon" type="image/x-icon" href="../images/SiSt.ico">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.6.1/jquery.min.js"></script>
<style>
table, td, th {
	border: solid 1px gray;
}

table {
	border-spacing: 3px;
	border-collapse: separate;
}

table, tr, td {
	/* border-radius: 3px; */
	/* padding:3px;  */
	
}
</style>
</head>
<body>
<h3>write.jsp</h3>
<!-- 4:05 수업 시작 -->
<div align="center">
  <h2>글 쓰기</h2>
  <!-- 
       action 속성 생략 : http://localhost/jspPro/cstvsboard/write.htm
     -> Write.java 서블릿 
             -> doPost()
    -->
  <form method="post">
  
  <table style="padding: 2px; width: 600px">
			<tr>
				<td colspan="2" align="center"><b>글을 적어주세요</b></td>
			</tr>
			<tr>
				<td align="center">이름</td>
				<td><input type="text" name="writer" size="15"
					autofocus="autofocus" required="required"></td>
			</tr>
			<tr>
				<td align="center">비밀번호</td>
				<td><input type="password" name="pwd" size="15" required="required"></td>
			</tr>
			<tr>
				<td align="center">Email</td>
				<td><input type="email" name="email" size="50" ></td>
			</tr>
			<tr>
				<td align="center">제목</td>
				<td><input type="text" name="title" size="50" required="required"></td>
			</tr>
			<tr>
				<td align="center">내용</td>
				<td><textarea name="content" cols="50" rows="10"></textarea></td>
			</tr>
			<tr>
				<td align="center">HTML</td>
				<td><input type="radio" name="tag" value="1" checked>적용
					<input type="radio" name="tag" value="0">비적용</td>
			</tr>
			<tr>
				<td colspan="2" align="center">
				  <input type="submit" value="작성 완료">
				  &nbsp;&nbsp;&nbsp; 
				  <input type="reset" value="다시 작성">
				  &nbsp;&nbsp;&nbsp; 
				  <a href="<%= contextPath %>/cstvsboard/list.htm">Home</a>
				</td>
			</tr>
		</table>
  
  </form>
</div>


<script>
    $(function (){
    	$("form").submit(function (){
    		  alert("유효성 검사 체크 한다. ");
    		  // event.preventDefault();
    		  // return false;
    	});
    });
</script>
</body>
</html>

editHandler.java

package days09.mvc.command;

import java.sql.Connection;
import java.sql.SQLException;

import javax.servlet.RequestDispatcher;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.util.ConnectionProvider;
import com.util.DBConn;

import days05.board.BoardDAOImpl;
import days05.board.BoardDTO;

public class EditHandler implements CommandHandler{

	@Override
	public String process(HttpServletRequest request, HttpServletResponse response) throws Exception {
		
		String requestMethod = request.getMethod(); 
		
		if(requestMethod.equals("GET")) {   
			 // 포워딩 
			int seq = Integer.parseInt(  request.getParameter("seq") );   		 
			Connection conn =  ConnectionProvider.getConnection();
			BoardDAOImpl dao = new BoardDAOImpl(conn);			
			BoardDTO dto = null; 
			try {			
				dto = dao.view(seq);
			} catch (SQLException e) {
				System.out.println("> EditHandler.process() Exception...");
				e.printStackTrace();
			} 		
			conn.close(); // 반환
			request.setAttribute("dto", dto);
			// 3. 포워딩
			return  "/days09/board/edit.jsp";      
			
		}else if(requestMethod.equals("POST")) {  // "POST"       
			 // 리다이렉트 
			request.setCharacterEncoding("UTF-8"); 
			int seq = Integer.parseInt(request.getParameter("seq")); 
			 
			String pwd = request.getParameter("pwd") ;
			String email = request.getParameter("email") ;
			String title = request.getParameter("title") ;
			String content  = request.getParameter("content") ;
			int tag = Integer.parseInt(  request.getParameter("tag") );
			
			BoardDTO dto = new BoardDTO(seq, null, pwd, email, title, null, 0, tag, content);
			
			Connection conn = ConnectionProvider.getConnection();
			BoardDAOImpl dao = new BoardDAOImpl(conn);
			int rowCount = 0;
			try {
				rowCount = dao.update(dto);
			} catch (SQLException e) {
				System.out.println("> EditHandler.process() Exception...");
				e.printStackTrace();
			}
			conn.close();
		 
			String location = "/jspPro/board/view.do?seq="+ seq;
			if( rowCount == 1) {
				location +="&edit=success";
			}else {
				location +="&edit=fail";
			}
			response.sendRedirect(location);
		} // 
		
		return null;
	}

}

View Handler

package days09.mvc.command;

import java.sql.Connection;
import java.sql.SQLException;

import javax.servlet.RequestDispatcher;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.util.ConnectionProvider;
import com.util.DBConn;

import days05.board.BoardDAOImpl;
import days05.board.BoardDTO;

public class ViewHandler implements CommandHandler {

	@Override
	public String process(HttpServletRequest request, HttpServletResponse response) throws Exception {
		
		int seq = Integer.parseInt(request.getParameter("seq"));
		
		Connection conn =  ConnectionProvider.getConnection();
		BoardDAOImpl dao = new BoardDAOImpl(conn);
		
		BoardDTO dto = null; 
		try {
			dao.increaseReaded(seq);
			dto = dao.view(seq);
		} catch (SQLException e) {
			System.out.println("> ViewHandler.process() Exception...");
			e.printStackTrace();
		} 		
		request.setAttribute("dto", dto);
		
		conn.close();  // 커넥션 풀에  반환
		
        // 3. 포워딩 		
		return "/days09/board/view.jsp";  
	}

}

editHandler.java

package days09.mvc.command;

import java.sql.Connection;
import java.sql.SQLException;

import javax.servlet.RequestDispatcher;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.util.ConnectionProvider;
import com.util.DBConn;

import days05.board.BoardDAOImpl;
import days05.board.BoardDTO;

public class EditHandler implements CommandHandler{

	@Override
	public String process(HttpServletRequest request, HttpServletResponse response) throws Exception {
		
		String requestMethod = request.getMethod(); 
		
		if(requestMethod.equals("GET")) {   
			 // 포워딩 
			int seq = Integer.parseInt(  request.getParameter("seq") );   		 
			Connection conn =  ConnectionProvider.getConnection();
			BoardDAOImpl dao = new BoardDAOImpl(conn);			
			BoardDTO dto = null; 
			try {			
				dto = dao.view(seq);
			} catch (SQLException e) {
				System.out.println("> EditHandler.process() Exception...");
				e.printStackTrace();
			} 		
			conn.close(); // 반환
			request.setAttribute("dto", dto);
			// 3. 포워딩
			return  "/days09/board/edit.jsp";      
			
		}else if(requestMethod.equals("POST")) {  // "POST"       
			 // 리다이렉트 
			request.setCharacterEncoding("UTF-8"); 
			int seq = Integer.parseInt(request.getParameter("seq")); 
			 
			String pwd = request.getParameter("pwd") ;
			String email = request.getParameter("email") ;
			String title = request.getParameter("title") ;
			String content  = request.getParameter("content") ;
			int tag = Integer.parseInt(  request.getParameter("tag") );
			
			BoardDTO dto = new BoardDTO(seq, null, pwd, email, title, null, 0, tag, content);
			
			Connection conn = ConnectionProvider.getConnection();
			BoardDAOImpl dao = new BoardDAOImpl(conn);
			int rowCount = 0;
			try {
				rowCount = dao.update(dto);
			} catch (SQLException e) {
				System.out.println("> EditHandler.process() Exception...");
				e.printStackTrace();
			}
			conn.close();
		 
			String location = "/jspPro/board/view.do?seq="+ seq;
			if( rowCount == 1) {
				location +="&edit=success";
			}else {
				location +="&edit=fail";
			}
			response.sendRedirect(location);
		} // 
		
		return null;
	}

}

edit.jsp

<%@ page contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<%@ taglib prefix="c"  uri="http://java.sun.com/jsp/jstl/core" %>
<%@ include file="/WEB-INF/inc/include.jspf"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>2022. 12. 8. 오후 3:28:25</title>
<link rel="shortcut icon" type="image/x-icon" href="../images/SiSt.ico">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.6.1/jquery.min.js"></script>
<style>
table, td, th {
	border: solid 1px gray;
}

table {
	border-spacing: 3px;
	border-collapse: separate;
}

table, tr, td {
	/* border-radius: 3px; */
	/* padding:3px;  */
	
}
</style>
</head>
<body>
<h3>edit.jsp</h3>
 
<div align="center">
  <h2>글 수정</h2>
  
  <form method="post">
  
  <table style="padding: 2px; width: 600px">
			<tr>
				<td colspan="2" align="center"><b>글을 수정합니다.</b></td>
			</tr>
			<tr>
				<td align="center">이름</td>
				<td><input type="text" name="writer" size="15"   value="${ dto.writer }"   disabled="disabled"></td>
			</tr>
			<tr>
				<td align="center">비밀번호</td>
				<td><input type="password" name="pwd" size="15" required="required"></td>
			</tr>
			<tr>
				<td align="center">Email</td>
				<td><input type="email" name="email" size="50"   value="${ dto.email }"></td>
			</tr>
			<tr>
				<td align="center">제목</td>
				<td><input type="text" name="title" size="50" required="required"  value="${ dto.title }"  autofocus="autofocus"></td>
			</tr>
			<tr>
				<td align="center">내용</td>
				<td><textarea name="content" cols="50" rows="10">${ dto.content }</textarea></td>
			</tr>
			<tr>
				<td align="center">HTML</td>
				<td>
				    <input type="radio" name="tag" value="1" >적용
					<input type="radio" name="tag" value="0">비적용
					<script>
					    $(":radio[name=tag][value=${ dto.tag }]").attr("checked", "checked");
					</script>
			    </td>
			</tr>
			<tr>
				<td colspan="2" align="center">
				  <input type="submit" value="작성 완료">
				  &nbsp;&nbsp;&nbsp;				  
				  <input type="button" onclick="history.back()" value="이전으로">
				</td>
			</tr>
		</table>
  
  </form>
</div>


<script>
    $(function (){
    	$("form").submit(function (){
    		  alert("유효성 검사 체크 한다. ");
    		  // event.preventDefault();
    		  // return false;
    	});
    });
</script>
</body>
</html>

deleteHandler.java

package days09.mvc.command;

import java.sql.Connection;
import java.sql.SQLException;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.util.ConnectionProvider;
import com.util.DBConn;

import days05.board.BoardDAOImpl;

public class DeleteHandler implements CommandHandler {

	@Override
	public String process(HttpServletRequest request, HttpServletResponse response) throws Exception {
		String requestMethod = request.getMethod();  
		if(requestMethod.equals("GET")) {
			return  "/days09/board/delete.jsp";
		}else if(requestMethod.equals("POST")) { 
			
			request.setCharacterEncoding("UTF-8");
			
			int seq = Integer.parseInt(  request.getParameter("seq") );  
			String pwd = request.getParameter("pwd");  
			
			Connection conn = ConnectionProvider.getConnection();
			BoardDAOImpl dao = new BoardDAOImpl(conn);
			int rowCount = 0;
			try {
				String originalPwd = dao.getOriginalPwd(seq); 
				if( originalPwd.equals(pwd) ) { 
					rowCount = dao.delete(seq);
				}else { 
					request.setAttribute("error", "비밀번호가 틀립니다.");
					return  "/days09/board/delete.jsp";
				}
			} catch (SQLException e) {
				System.out.println("> DeleteHandler.process() Exception...");
				e.printStackTrace();
			}
			conn.close();
			
			 
			String location = "/jspPro/board/list.do";
			if( rowCount == 1) {
				location +="?delete=success";
			}else {
				location +="?delete=fail";
			}
			response.sendRedirect(location);
			
		} // if
		
		return null;
	}

}

<%@ page contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<%@ taglib prefix="c"  uri="http://java.sun.com/jsp/jstl/core" %>
<%@ include file="/WEB-INF/inc/include.jspf" %>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>2022. 12. 9. 오후 3:38:00</title>
<link rel="shortcut icon" type="image/x-icon" href="../images/SiSt.ico">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.6.1/jquery.min.js"></script>
<style>
 table , td, th {
   border:solid 1px gray;
 }
 table{
     border-spacing: 3px;
     border-collapse: separate;
   }
   table,  tr, td {
    /* border-radius: 3px; */
    /* padding:3px;  */
   }
 table{
    width: 600px;
 }
</style>
</head>
<body>
<h3>delete.jsp</h3>

<div align="center">
  <h2>삭제하기</h2>
  <form method="post">
	<table>
	  <tr>
	    <td colspan="2" align="center"><b>글을 삭제합니다</b></td>
	  </tr>
	  <tr>
	    <td align="center">비밀번호</td>
	    <td>
	      <input type="password" name="pwd" size="15" autofocus="autofocus">
	    </td>
	  </tr>
	  <tr>
	    <td colspan="2" align="center">
	      <input type="submit" value="삭제">&nbsp;&nbsp;
	      <input type="button" id="cancel" value="취소">
	    </td>
	  </tr>
	</table>
  </form>
</div>

<script>
<%
      String pwdError = (String)request.getAttribute("error");
       if(  pwdError != null){
 %>
              alert( '<%= pwdError %>');
 <%
       }
%> 
</script>
</body>
</html>

1. days09

ㄴ board

ㄴ list.jsp

글쓰기 링크 태그 href 속성 확인/수정

<a href="<%= contextPath %>/cstvsboard/write.htm">글쓰기</a>

==> <a href="<%= contextPath %>/board/write.do">글쓰기</a>

2. 확인/코딩~

[MVC 처리 과정 이해 ]

/board/write.do => MV[C] doGet(){}

(1) WriteHandler 클래스 생성

(2) commandHandler.properties 확인/수정/추가

/board/write.do=days09.mvc.command.WriteHandler

(3) WriteHandler.process() 구현

- 로직 처리 담당

- ( days05.board.Write.java 서블릿 )

doGet(){

write.jsp 페이지로 포워딩.

}

doPost(){

BoardDTO dto;

DB insert()

list.htm 리다이렉트

}

( 문제점 ) 하나의 process() 메서드에서 doget(), dopost() 기능을 모두

해야 되는 문제점 ..

해결은 아래 코딩으로 해결~~

if(requestMethod.equals("GET")) {

}else if(requestMethod.equals("POST")) {

}

[게시글 상세보기(View.jsp)]

1. 확인/[수정]/추가

보고자 하는 게시글의 제목을 클릭하면 요청

http://localhost/jspPro/cstvsboard/view.htm

seq=381&currentpage=1&searchCondition=1&searchWord=

list.jsp

/board/view.do 수정

2. 확인/수정/추가

(1) /board/view.do= ViewHandler 클래스 확인

process(){} View.java 복사 붙여서 수정.

(2) commandHandler.properties 파일 확인/수정.

[내용보기] view.jsp

[수정하기] ***

1. <a class="btn btn-secondary" href="<%= contextPath %>/board/edit.do?seq=${ dto.seq }" id="editLink">수정하기</a>

2. /board/edit.do => EditHandler.java 확인/추가

WriteHandler.java 복사 붙이기..

commandHandler.properties 파일 확인/수정.

[내용보기] view.jsp

[모달창으로 글 삭제] 클릭하면

[삭제 모달창]

비밀번호 입력 후 [삭제]버튼 클릭

1) /board/delete.do 요청

view.jsp 열어서 모달 div 확인..

<form method="post" action="<%= contextPath%>/board/delete.do?seq=${ param.seq}"> 수정.

2) DeleteHandler.java 추가.

commandHandler.properties 파일 확인/수정.

p 544 Chapter 19 필터( Filter ) -- [ 프로젝트 할때 사용 기술 ]

- 필터

- Filter 구현

- 로그인 검사 등등 필터 응용.

예)

list.do -> 요청 -> jsp/servlet

인증

권한

필터를 사용해서 체크

<-응답<- [응답데이터]

xml 변환 시켜서 응답

암호화 시켜서 응답

- 필터 체인 : 여러 개의 필터가 모여서 형성된 것.

[- 필터 구현 : 핵심 3개 타입 ]

1) javax,servlet.Filter 인터페이스

init() 필터 객체가 생성될 때 호출되는 메서드 , 초기화.

*** doFilter() : 인증/권한

필터 기능을 하는 메서드 + 다음 필터 / 최종 자원(jsp/servlet ) 체인

destory() 필터 객체가 소멸될 때 호출되는 메서드, 리소스 반환

2) javax.servlet.ServletRequestWrapper 클래스

- request(요청)-> 요청 파라미터 변경

3) javax.servlet.ServletResponseWrapper 클래스

- 응답 변경..

- 필터 클래스를 사용하려면

톰캣\lib\servlet-api.jar 파일을 클래스 패스에 추가해야 되지만

이클립스를 사용해서 개발할 경우에는 추가할 필요가 없다.

[ 필터 설정하는 2가지 방법]

1) web.xml 필터 설정

2) @WebFilter 애노테이션을 사용.

p 552 까지 정리~~

[ 실습 예제 ] 추가 설명

ex04.jsp

ex04_ok.jsp

// 내일 실제 실습 예제 ( 인증, 권한 )

// Chapter 20 ServletContextListener

// Chapter 15 방명록 MVC 패턴 구현

예시)

<!--

web_days09_mvc.xml 복사 붙이기

필터 생성 - post 요청/ 인코딩 설정.

1. com.filter.CharacterEncondingFilter 필터 클래스 추가.

-->

<form action="ex04_ok.jsp" method="post">
    한글 이름 : <input type="text" name="name" value="홍길동"><br>
    나이 : <input type="text" name="age" value="20"><br>
    <input type="submit">
</form>

<%
     String name = request.getParameter("name");
     String age = request.getParameter("age");
%>

전달된 이름 : <%= name %><br> <!-- íê¸¸ë   post  ISO 8859-1 인코딩 -->
전달된 나이 : <%= age %><br>

package com.filter;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;

public class CharacterEncodingFilter implements Filter{

	@Override
	public void init(FilterConfig filterConfig) throws ServletException {
		
	}	

	@Override
	public void doFilter(ServletRequest request, ServletResponse response
			, FilterChain chain)
			throws IOException, ServletException { 
		System.out.println("> CharacterEncodingFilter.doFilter() 호출됨.");
		request.setCharacterEncoding("UTF-8");		
		chain.doFilter(request, response);
	}

	@Override
	public void destroy() { 
		
	}
}

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