Servlet 请求转发

package com.xxxx.servlet;

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 java.io.IOException;
@WebServlet("/04")
public class Servlet4 extends HttpServlet {
    @Override
    protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        /**
         * 请求转发
         *      请求从服务端跳转到客户端/指定Servlet
         */
        String uname=req.getParameter("uname");
        System.out.println("S4"+uname);
        //请求转发到4_1
      //  req.getRequestDispatcher("041").forward(req,resp);
        //请求转发到jsp页面
       // req.getRequestDispatcher("login.jsp").forward(req,resp);
        //请求转发到html页面
        req.getRequestDispatcher("login.html").forward(req,resp);
    }
}

package com.xxxx.servlet;

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 java.io.IOException;
@WebServlet("/041")
public class Servlet4_1 extends HttpServlet {
    @Override
    protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        String uname=req.getParameter("uname");
        System.out.println("S41"+uname);
    }
}

action路径问题

假设 servlet value为"/test"
对action值来说
/代表根目录，如果使用/开头，对于Tomcat而言就是webApp那个目录，直接找相应的servlet当然找不到，只要再加上项目名即可。
action = /login 开头对应的路径：http://localhost:8080/login ，如果有项目路径肯定无法访问到
action = login,这里用的是相对目录(即当前项目目录，tomcat配置里面的URL)，相对于http://localhost：8080/test
所以这个action请求的servlet地址：http://localhost:8080/springmvc/login

<%--
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  User: 
  Date: 2022/3/30
  Time: 20:44
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>login</title>
</head>
<body>
    <form action="s03" method="get">
        name:<input type="text" name="uname"><br>
        pass:<input type="text" name="upwd"><br>
        <button>submit</button>
    </form>
</body>
</html>