【JSP开发】response重定向和resquest转发

response重定向

package cn.edu.Response;


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


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


//实现请求重定向
/*
 重定向的特点：
 1.浏览器会向服务器发送两次请求，意味着就有两个request和response
 2.用重定向技术，浏览器地址栏会发生变化
   用户登录和显示购物车时，通常会用到重定向技术
 */
public class ResponseDemo7 extends HttpServlet {


	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {


		response.sendRedirect("/day06/index.jsp");
	}


	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
      doGet(request,response);
	}


}

package cn.edu.Request;


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


import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
//请求转发，以及使用request域对象把数据带给转发资源
//请求转发的特点：
//1.客户端只发出一次请求，服务器端有多个资源调用
//2.浏览器地址栏没有变化
public class RequestDemo5 extends HttpServlet {


	//MVC(model   javabean   V   View(jsp)   C   Controller(servlet))
	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
        
		String data="aaaaa";
		
		request.setAttribute("data",data);
		
		//request实现转发
		request.getRequestDispatcher("/message.jsp").forward(request, response);
	}


	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
       doGet(request,response);
	}


}