request.getRequestDispatcher(url)的url可以是相对路径也可以是绝对路径。
getRequestDispatcher分成两种，可以用request调用，也可以用getServletContext()调用 不同的是this.getServletContext().getRequestDispatcher(url)的url只能是绝对路径。
package com.kuang.servlet;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.Arrays;
public class Login extends HttpServlet {
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
req.setCharacterEncoding("utf-8");
resp.setCharacterEncoding("utf-8");
String username = req.getParameter("username");
String password = req.getParameter("password");
String[] hobbies = req.getParameterValues("hobbies");
System.out.println("=======================");
System.out.println("username:"+username);
System.out.println("password:"+password);
System.out.println("hobbies:"+ Arrays.toString(hobbies));
System.out.println("=======================");
System.out.println(req.getContextPath());
req.getRequestDispatcher("/success.jsp").forward(req,resp);
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
doGet(req, resp);
}
}
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>登录</title>
</head>
<body>
<h1>登录</h1>
<div>
<form action="${pageContext.request.contextPath}/Login" method="post">
用户名<input type="text" name="username"><br>
密码<input type="password" name="password"><br>
爱好:<input type="checkbox" name="hobbies" value="女人">女人
<input type="checkbox" name="hobbies" value="篮球">篮球
<input type="checkbox" name="hobbies" value="唱歌">唱歌
<input type="checkbox" name="hobbies" value="跳舞">跳舞 <br>
<input type="submit">
</form>
</div>
</body>
</html>
<%--
Created by IntelliJ IDEA.
User: 蒋铭基
Date: 2023/4/15
Time: 19:43
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>Title</title>
</head>
<body>
<h1>success</h1>
</body>
</html>
<servlet>
<servlet-name>Login</servlet-name>
<servlet-class>com.kuang.servlet.Login</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>Login</servlet-name>
<url-pattern>/Login</url-pattern>
</servlet-mapping>
默认前面有一条/
