【发布时间】：2020-05-12 19:04:38
【问题描述】：
我正在学习 JSP/Servet 并尝试制作一个简单的 Servlet 控制器。
这是我的项目结构：
test是首页，用户可以输入自己的爱好。确认页面，将向用户确认详细信息。它可以选择返回并编辑信息或将信息提交到 process.jsp 页面。
web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://xmlns.jcp.org/xml/ns/javaee"
xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
id="WebApp_ID" version="4.0">
<servlet>
<servlet-name>FirstController</servlet-name>
<servlet-class>ch2.servletController.Controller</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>FirstController</servlet-name>
<url-pattern>/ch2/servletController/Controller</url-pattern>
</servlet-mapping>
</web-app>
Test.jsp
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<!DOCTYPE html>
<html lang="eu">
<head>
<meta charset="UTF-8">
<title>Simple web page</title>
</head>
<body>
<p>
This is a simple HTML page that has a form in it.
<form action="ch2/servletController/Controller">
<p>
Hobby:<input type="text" name="hobby" value="${param.hobby}">
<input type="submit" name ="confirmButton" value="confirm">
</form>
</body>
</html>
确认.jsp
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="ISO-8859-1">
<title>Confirm Page</title>
</head>
<body>
<p>
The value of the hobby that was sent to this page is <strong>${param.hobby} </strong>.
<p>
<form action="ch2/servletController/Controller">
<p>
If there is any error, please click the edit button and
to process press the Submit button <br>
<input type="hidden" name="hobby" value="${param.hobby}">
<input type="submit" name="editButton" value="Edit">
<input type="submit" name="submit" value="submit">
</form>
</body>
</html>
Process.jsp
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="ISO-8859-1">
<title>Process Page</title>
</head>
<body>
Thank you for your information, Your hobby of <strong>${param.hobby} </strong> will
be added to our records, eventually.
</body>
</html>
Controller.java
package ch2.servletController;
import java.io.IOException;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
@WebServlet("/Controller")
public class Controller extends HttpServlet {
private static final long serialVersionUID = 1L;
protected void doGet(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException
{
String address;
if(request.getParameter("submit") != null)
{
address = "Process.jsp";
}
else if ( request.getParameter("editButton") != null)
{
address = "test.jsp";
}
else
{
address = "/Confirm.jsp";
}
RequestDispatcher dispatcher =
request.getRequestDispatcher(address);
dispatcher.forward ( request, response);
}
}
但是我无法返回 test.jsp 页面和 Process.jsp 页面：
这是我在单击 confirm.jsp 页面的编辑按钮时遇到的错误。
我注意到我不是正确的路径，甚至 servlet 位置也在重复。是否可以解释为什么 servlet 位置重复以及如何通过控制器成功导航到 test.jsp？
非常感谢您提前提供反馈。
编辑1：
感谢 areus 的反馈。修改confirm.jsp 上的操作后，我收到以下错误。 URL 不再重复，但无法返回。
请找到confirm.jsp的HTML代码：
<!DOCTYPE html>
<html>
<head>
<meta charset="ISO-8859-1">
<title>Confirm Page</title>
</head>
<body>
<p>
The value of the hobby that was sent to this page is <strong>web programming </strong>.
<p>
<form action="/ch2/servletController/Controller">
<p>
If there is any error, please click the edit button and
to process press the Submit button <br>
<input type="hidden" name="hobby" value="web programming">
<input type="submit" name="Edit" value="Edit">
<input type="submit" name="submit" value="submit">
</form>
</body>
</html>
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