RequestDispatcher 클래스

받은 요청을 다른 컴퍼넌트에 위임
요청받은 컴퍼넌트와 위임받은 컴퍼넌트의 request 객체가 같다

dispacherJsp.jsp

<%@ page language="java" contentType="text/html; charset=EUC-KR"
	pageEncoding="EUC-KR"%>
<!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=EUC-KR">
<title>Insert title here</title>
</head>
<body>

	dispacherJsp.jsp
	<hr />

	id :
	<%=request.getAttribute("id")%>
	<br /> pw :
	<%=request.getAttribute("pw")%>


	<!--jsp에서도 RequestDispatcher를 생성해서 다른 곳으로 요청을 위임할 수 있음
		RequestDispatcher dispatcher = request.getRequestDispatcher("/dispacherJsp.jsp");
		dispatcher.forward(request, response); -->
</body>
</html>

RequestObj.java

package com.javalec.ex;

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;

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

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

	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		System.out.println("doPost");
		actionDo(request, response);
	}
	
	private void actionDo(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		System.out.println("actionDo");
		
		request.setAttribute("id", "abcde");
		request.setAttribute("pw", "12345");
		
		//생성 단계 getRequestDispatcher("/dispacherJsp.jsp") : 위임 받을 컴퍼넌트의 위치
		RequestDispatcher dispatcher = request.getRequestDispatcher("/dispacherJsp.jsp");
		dispatcher.forward(request, response);
		
	}

}

HttpServletResponse

RequestDispatcher와 의 차이점: 위임받은 컴퍼넌트와 요청받은 컴퍼넌트가 사용하는 request 객체가 다르다
redirect.jsp

<%@ page language="java" contentType="text/html; charset=EUC-KR"
    pageEncoding="EUC-KR"%>
<!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=EUC-KR">
<title>Insert title here</title>
</head>
<body>

		<%
			request.setAttribute("id", "abcde");
			request.setAttribute("pw", "12345");
			
			//HttpSevletResponse의 객체
			response.sendRedirect("RequestObj");
		%>

</body>
</html>

RequestObj.java

package com.javalec.ex;

import java.io.IOException;
import java.io.PrintWriter;

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;

/**
 * Servlet implementation class RequestObj
 */
@WebServlet("/RequestObj")
public class RequestObj extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public RequestObj() {
        super();
    }

	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		System.out.println("doGet");
		actionDo(request, response);
	}

	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		System.out.println("doPost");
		actionDo(request, response);
	}
	
	private void actionDo(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
	
		System.out.println("actionDo");
		
		
		//redirect.jsp와 request 객체가 다르므로 redirect.jsp에서 입력한 값이 아닌, null
		String id = (String)request.getAttribute("id");
		String pw = (String)request.getAttribute("pw");
		
		response.setContentType("text/jhtml; charset=EUC-KR");
		PrintWriter writer = response.getWriter();
		writer.print("<html><head></head><body>");
		writer.print("RequestObj" + "<hr />");
		writer.print("id : " + id + "<br />");
		writer.print("pw : " + pw);
		writer.print("</body></html>");
		
	}

}

Author And Source

이 문제에 관하여(JSP| 포워딩), 우리는 이곳에서 더 많은 자료를 발견하고 링크를 클릭하여 보았다 https://velog.io/@kji306301/JSP-포워딩

우수한 개발자 콘텐츠 발견에 전념 (Collection and Share based on the CC Protocol.)

JSP| 포워딩

RequestDispatcher 클래스

HttpServletResponse

Author And Source

좋은 웹페이지 즐겨찾기