javaweb学习中的路径问题

2024-11-11 技术教程

1. 项目结构

2. 客户端路径

1. 超链接

2. 表单

<%@ 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>页面b</title></head><body>   <form action="http://localhost:8080/testPath/jsp/b.jsp" methoe="get"> username:<input type="text" name="username" value=""> <input type="submit" value="提交---绝对地址 "> </form>  <form action="/testPath/jsp/b.jsp" methoe="get"> username:<input type="text" name="username" value=""> <input type="submit" value="提交---以/开头的相对地址"> </form> <form action="b.jsp" methoe="get"> username:<input type="text" name="username" value=""> <input type="submit" value="提交---不以/开头的相对地址 "> </form>     <form action="http://localhost:8080/testPath/PathServlet" methoe="get"> username:<input type="text" name="username" value=""> <input type="submit" value="表单提交到Servlet---绝对地址"> </form>   <form action="/testPath/PathServlet" methoe="get"> username:<input type="text" name="username" value=""> <input type="submit" value="表单提交到Servlet---以/开头的相对地址"> </form>   <form action="../PathServlet" methoe="get"> username:<input type="text" name="username" value=""> <input type="submit" value="表单提交到Servlet---不以/开头的相对地址"> </form></body></html>

3.重定向

package cn.test.path;import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.annotation.WebServlet;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;/** * @author Guozhen_Zhao * 创建时间：2018年3月17日上午10:12:21 * 备注：重定向有三种路径书写方式 : * 1. 绝对路径 * 2. 以"/"开头的相对路径 * 3. 不以"/"开头的相对路径 */@WebServlet("/RedirectServlet")public class RedirectServlet extends HttpServlet { private static final long serialVersionUID = 1L; protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.sendRedirect("http://localhost:8080/testPath/jsp/b.jsp"); /* * 2.以"/"开头的相对路径 * 此时，/代表整个web工程的路径，即http://localhost:8080/ */ // response.sendRedirect("/testPath/jsp/b.jsp"); /* * 3.不以"/"开头的相对路径 * 此时是相对于当前资源的相对路径 * 当前资源路径为:http://localhost:8080/testPath/RedirectServlet * 即表示:RedirectServlet在路径http://localhost:8080/testPath之下 * 而b.jsp在http://localhost:8080/testPath/jsp/b.jsp * 所以最终地址写为:jsp/b.jsp */ // response.sendRedirect("jsp/b.jsp"); } protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); }}服务器端路径

请求转发

package cn.test.path;import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.annotation.WebServlet;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;/** * @author Guozhen_Zhao * 创建时间：2018年3月17日上午10:09:59 * 备注：服务器端的路径不能是绝对路径，只能是相对路径，也分为以/开头和不以/开头两种 * 1.以"/"开头的相对路径 * 2.不以"/"开头的相对路径 */@WebServlet("/DispatcherServlet")public class DispatcherServlet extends HttpServlet { private static final long serialVersionUID = 1L; protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { /* * 1.以"/"开头的相对路径 * 此时，/代表当前web项目，即:http://localhost:8080/javaee */ // request.getRequestDispatcher("/jsp/b.jsp").forward(request, response); /* * 2.不以"/"开头的相对路径 * 相对于当前资源的相对路径 * 此时，当前资源的路径为:http://localhost:8080/javaee/DispatcherServlet * 所以要转发去的资源的路径以:http://localhost:8080/javaee开头 */ request.getRequestDispatcher("jsp/b.jsp").forward(request, response); } protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); }}