我想将用户数据保存到动态Web应用程序中的数据库中，我使用hibernate保存到db中，我的注册页面（signup.html）包含许多字段，并且格式为action =“ rs” RegisterServlete，但我不知道为什么我会收到此错误
HTML： signup.html
<!DOCTYPE html>
<html>
<head>
<meta charset="ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
<h1 align="center">REGISTER</h1>
<form action="rs" method="post">
<table>
<!----- First Name ---------------------------------------------------------->
<tr>
<td>FIRST NAME</td>
<td><input type="text" name="First_Name" maxlength="30" /> (max
30 characters a-z and A-Z)</td>
</tr>
<!----- Last Name ---------------------------------------------------------->
<tr>
<td>LAST NAME</td>
<td><input type="text" name="Last_Name" maxlength="30" /> (max
30 characters a-z and A-Z)</td>
</tr>
<!----- Date Of Birth -------------------------------------------------------->
<tr>
<td>AGE</td>
<td><input type="number" name="age" maxlength="10" /></td>
</tr>
<!----- Email Id ---------------------------------------------------------->
<tr>
<td>EMAIL ID</td>
<td><input type="text" name="Email_Id" maxlength="100" /></td>
</tr>
<!----- Mobile Number ---------------------------------------------------------->
<tr>
<td>MOBILE NUMBER</td>
<td><input type="text" name="Mobile_Number" maxlength="10" />
(10 digit number)</td>
</tr>
<!----- Gender ----------------------------------------------------------->
<tr>
<td>GENDER</td>
<td>Male <input type="radio" name="Gender" value="Male" />
Female <input type="radio" name="Gender" value="Female" />
</td>
</tr>
<!----- Address ---------------------------------------------------------->
<!----- City ---------------------------------------------------------->
<tr>
<td>CITY</td>
<td><input type="text" name="City" maxlength="30" /> (max 30
characters a-z and A-Z)</td>
</tr>
<!----- Pin Code ---------------------------------------------------------->
<tr>
<td>PIN CODE</td>
<td><input type="text" name="Pin_Code" maxlength="6" /> (6
digit number)</td>
</tr>
<!----- State ---------------------------------------------------------->
<tr>
<td>STATE</td>
<td><input type="text" name="State" maxlength="30" /> (max 30
characters a-z and A-Z)</td>
</tr>
<!----- Country ---------------------------------------------------------->
<tr>
<td>COUNTRY</td>
<td><input type="text" name="Country" value="India"
readonly="readonly" /></td>
</tr>
<tr>
<td>PASSWORD</td>
<td><input type="password" name="Password" maxlength="30"
min="8" /></td>
</tr>
<tr>
<td>CONFIRM PASSWORD</td>
<td><input type="password" name="Con_password" maxlength="30"
min="8" /></td>
</tr>
<!----- Submit and Reset ------------------------------------------------->
<tr>
<td colspan="2" align="center"><input type="submit"
value="SIGN UP"></td>
</tr>
</table>
</form>
</body>
</html>
Java： RegisterServlet.java
`package com.train.seat.exchange;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import com.train.seat.exchange.dao.UserDAO;
import com.train.seat.exchange.dto.UserDTO;
public class RegisterServlet extends HttpServlet {
public RegisterServlet() {
System.out.println("RegisterServlet started");
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
UserDTO user = new UserDTO();
user.setfName(req.getParameter("First_Name"));
user.setlName(req.getParameter("Last_Name"));
user.setAge(Integer.parseInt("age"));
user.setEmail(req.getParameter("Email_Id"));
user.setMobileNum(Long.parseLong("Mobile_Number"));
user.setGender(req.getParameter("Gender"));
user.setCity(req.getParameter("City"));
user.setState(req.getParameter("State"));
user.setPinCode(Integer.parseInt("Pin_Code"));
user.setCountry(req.getParameter("Country"));
user.setPassword(req.getParameter("Password"));
HttpSession session = req.getSession(true);
UserDAO userdao = new UserDAO();
userdao.registeruser(user);
resp.sendRedirect("login.html");
}
}`
web.xml：
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://java.sun.com/xml/ns/javaee"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
version="3.0">
<display-name>TrainSeatExchange</display-name>
<welcome-file-list>
<welcome-file>signup.html</welcome-file>
</welcome-file-list>
<servlet>
<servlet-name>RegisterServlet</servlet-name>
<servlet-class>com.train.seat.exchange.RegisterServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>RegisterServlet</servlet-name>
<url-pattern>/rs</url-pattern>
</servlet-mapping>
</web-app>
