关于springMVC和传统servlet框架从jsp页面向后台请求url问题

来源：互联网发布：ge 段小缨知乎编辑：程序博客网时间：2024/06/14 00:08

经过实验发现

servlet和springmvc向后台发送请求都是根据request.getServletPath()来获取请求的

如果jsp中没有<base href="<%=basePath%>">则向后台的请求会自动解析到项目根目录下加上以后会自动解析到文件的当前目录下
举个例子

如上图项目(两个jsp内容一样)

jsp内容

<%@ page language="java" contentType="text/html; charset=UTF-8"    pageEncoding="UTF-8"%><!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=UTF-8"><title>Insert title here</title></head><body><form action="login.action" method="post">用户名<input type="text" name="userName">密码<input type="text" name="password"><input type="submit" value="submit"></form></body></html>

Test是个servlet代码如下

package com;import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;/** * Servlet implementation class Test */public class Test extends HttpServlet {private static final long serialVersionUID = 1L;           /**     * @see HttpServlet#HttpServlet()     */    public Test() {        super();        // TODO Auto-generated constructor stub    }/** * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response) */protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {this.doPost(request, response);}/** * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response) */protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {System.out.println("request.getServletPath()="+request.getServletPath());System.out.println("request.getContextPath()="+request.getContextPath());}}

1.此时浏览器输入http://localhost:8080/TestServlet/page/NewFile.jsp
控制台输出

request.getServletPath()=/page/login.action
request.getContextPath()=/TestServlet

2.浏览器输入http://localhost:8080/TestServlet/page/a/NewFile.jsp
控制台输出
request.getServletPath()=/page/a/login.action
request.getContextPath()=/TestServlet

-----------------------------------------------------------------------------------------------------------------------------------------------------------------

如果在两个jsp中加入basepath
jsp代码如下

<%@ page language="java" contentType="text/html; charset=UTF-8"    pageEncoding="UTF-8"%>    <%String path = request.getContextPath();String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";%><!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><html><head><base href="<%=basePath%>" /><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><title>Insert title here</title></head><body><form action="login.action" method="post">用户名<input type="text" name="userName">密码<input type="text" name="password"><input type="submit" value="submit"></form></body></html>

1.此时浏览器输入http://localhost:8080/TestServlet/page/NewFile.jsp

控制台输出
request.getServletPath()=/login.action
request.getContextPath()=/TestServlet

2.浏览器输入http://localhost:8080/TestServlet/page/a/NewFile.jsp
控制台输出
request.getServletPath()=/login.action
request.getContextPath()=/TestServlet

通过以上实验可以看出request.getServletPath()在jsp中加入basepath的时候会直接获取到请求如果不加会从项目根目录开始获取请求路径

在springMVC中是一样的道理 springMVC实际也是通过request.getServletPath()获取请求的

springMVC和servlet都是根据这种获取的请求并解析所以当用springmvc发送请求报404的时候后台报no mapping时可能会是这个原因(请求路径不对应)

ps：这个basePath代码
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<base href="<%=basePath%>" />

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