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Я новичок в сервлетах Java. Я googled для того, чтобы создать простую форму входа с проверкой базы данных mysql. Я сделал так много изменений и по какой-то причине по-прежнему имею следующую ошибку.Ошибка в форме входа
Следующий тип ошибки:
HTTP Status 404 - /LoginServlet
type Status report
message /LoginServlet
description The requested resource is not available.
Apache Tomcat/7.0.57
Здесь все мои страницы JSP и объекты Java и web.xml:
index.jsp
<%@ page language="java" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1"%>
<!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=ISO-8859-1">
<title>Login Page</title>
</head>
<body>
<center>
<h1>Login Details</h1>
<form action="/LoginServlet" method="POST">
<br/>Username:<input type="text" name="username">
<br/>Password:<input type="password" name="password">
<br/><input type="submit" value="Submit">
</form>
</center>
</body>
</html>
welcome.jsp
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Welcome <%=session.getAttribute("name")%></title>
</head>
<body>
<h3>Login successful!!!</h3>
<h4>
Hello,
<%= session.getAttribute("name")%>
</h4>
</body>
</html>
LoginServlet.java упаковка com.servlet;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.RequestDispatcher;
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.logindao.LoginDao;
public class LoginServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
response.setContentType("text/html");
PrintWriter out = response.getWriter();
String n=request.getParameter("username");
String p=request.getParameter("password");
HttpSession session = request.getSession(false);
if(session!=null)
session.setAttribute("username", n);
if(LoginDao.validate(n, p)){
RequestDispatcher rd=request.getRequestDispatcher("welcome.jsp");
rd.forward(request,response);
}
else{
out.print("<p style=\"color:red\">Sorry username or password error</p>");
RequestDispatcher rd=request.getRequestDispatcher("index.jsp");
rd.include(request,response);
}
out.close();
}
}
LoginDao.java
package com.logindao;
import java.sql.*;
public class LoginDao {
public static boolean validate(String name, String pass) {
boolean status = false;
Connection conn = null;
PreparedStatement pst = null;
ResultSet rs = null;
String url = "jdbc:mysql://localhost:3306/";
String dbName = "form";
String driver = "com.mysql.jdbc.Driver";
String userName = "root";
String password = "password";
try {
Class.forName(driver).newInstance();
conn = DriverManager.getConnection(url + dbName, userName, password);
pst = conn.prepareStatement("select * from login where user=? and password=?");
pst.setString(1, name);
pst.setString(2, pass);
rs = pst.executeQuery();
status = rs.next();
} catch (Exception e) {
System.out.println(e);
} finally {
if (conn != null) {
try {
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if (pst != null) {
try {
pst.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if (rs != null) {
try {
rs.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
return status;
}
}
web.xml
<?xml version="1.0" encoding="ISO-8859-1"?>
<web-app xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
version="3.0">
<servlet>
<servlet-name>login</servlet-name>
<servlet-class>com.servlet.LoginServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>login</servlet-name>
<url-pattern>/LoginServlet</url-pattern>
</servlet-mapping>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
</web-app>
Я до сих пор та же ошибка: HTTP Status 404 -/LoginServlet типа отчет Статуса сообщения/LoginServlet описания Запрашиваемого ресурс не доступен. Apache Tomcat/7.0.57 – user3158406