[学习笔记]马士兵 Servlet & JSP(3.Servlet和JSP的通信)

（1）从JSP调用Servlet可用，请求信息自动转到Servlet

FromJspToServlet.jsp

   
       
       
   

（2）从Servlet调用JSP可以使用RequestDispatcher接口的forward(req, resp)方法，请求信息需要显示传递

ServletToJSP.java

import java.io.IOException;

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

public class ServletToJSP extends HttpServlet {

    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
       
        // 设置属性并将它分发给/servlet_jsp/ServletUseJsp.jsp处理
        resp.setContentType("text/html;charset=gb2312");
        req.setAttribute("servletName", "ServletToJSP");
        // RequestDispatcher getRequestDispatcher(String path):
        // Returns a RequestDispatcher object that acts as a wrapper for the resource located at the given path.
        getServletConfig().getServletContext().getRequestDispatcher("/servlet_jsp/ServletUseJsp.jsp").forward(req, resp);
    }

}

（3）ServletUseJsp.jsp

< contentType="text/html;charset=gb2312" %>

   
   
       
   
   
   
       

Servlet使用JSP的例子

       

这个页面是被Servlet调用的

   

 

说明：以上相互调用也可以直接使用sendRedirect