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用户登录需要和数据库进行匹配.
这是数据库中的表.
| id | userame | password | |
| 1 | Tom | 1234 | [email protected] |
| 2 | Jerry | 1234 | [email protected] |
登录页面
<!DOCTYPE html>
<html>
<head>
<title>login.html</title>
<meta name="keywords" content="keyword1,keyword2,keyword3">
<meta name="description" content="this is my page">
<meta name="content-type" content="text/html; charset=UTF-8">
</head>
<body>
<form action="/WEB01/login" method="post">
Username:<input type="text" name="username"><br />
Password:<input type="password" name="password"><br />
<input type="submit" value="Login"><br />
</form>
</body>
</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_2_5.xsd" id="WebApp_ID" version="2.5">
<display-name>WEB13</display-name>
<context-param>
<param-name>driver</param-name>
<param-value>com.mysql.jdbc.Driver</param-value>
</context-param>
<servlet>
<servlet-name>abc</servlet-name>
<servlet-class>com.itheima.servlet.QuickStratServlet</servlet-class>
<init-param>
<param-name>url</param-name>
<param-value>jdbc:mysql:///mydb</param-value>
</init-param>
<load-on-startup>3</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>abc</servlet-name>
<url-pattern>/quickStratServlet</url-pattern>
</servlet-mapping>
<welcome-file-list>
<welcome-file>1.html</welcome-file>
<welcome-file>index.html</welcome-file>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>
<servlet>
<servlet-name>QuickStartServlet2</servlet-name>
<servlet-class>com.itheima.servlet.QuickStartServlet2</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>QuickStartServlet2</servlet-name>
<url-pattern>/quickStartServlet2</url-pattern>
</servlet-mapping>
<servlet>
<description></description>
<display-name>LoginServlet</display-name>
<servlet-name>LoginServlet</servlet-name>
<servlet-class>com.itheima.login.LoginServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>LoginServlet</servlet-name>
<url-pattern>/login</url-pattern>
</servlet-mapping>
<servlet>
<description></description>
<display-name>ContextServlet</display-name>
<servlet-name>ContextServlet</servlet-name>
<servlet-class>com.itheima.context.ContextServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>ContextServlet</servlet-name>
<url-pattern>/context</url-pattern>
</servlet-mapping>
<servlet>
<description></description>
<display-name>ContextServlet2</display-name>
<servlet-name>ContextServlet2</servlet-name>
<servlet-class>com.itheima.context.ContextServlet2</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>ContextServlet2</servlet-name>
<url-pattern>/context2</url-pattern>
</servlet-mapping>
</web-app>package com.web.login;
import java.io.IOException;
import java.sql.SQLException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.BeanHandler;
import com.web.domain.User;
import com.web.utils.DataSourceUtils;
public class LoginServlet extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
// 获得用户名和密码
String username = request.getParameter("username");
String password = request.getParameter("password");
// 从数据库中验证用户名和密码是否匹配
QueryRunner runner = new QueryRunner(DataSourceUtils.getDataSource());
String sql = "select * from user where username=? and password=?";
User user = null;
try {
user = runner.query(sql, new BeanHandler<User>(User.class),
username, password);
} catch (SQLException e) {
e.printStackTrace();
}
// 根据返回的结果给出讯息
if (user != null) {
// 登录成功
response.getWriter().write("Login success");
response.getWriter().write(user.toString());
} else {
// 登录失败
response.getWriter().write("Login failure");
}
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request, response);
}
}package com.web.domain;
public class User {
private int id;
private String username;
private String password;
private String email;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
@Override
public String toString() {
return "User [id=" + id + ", username=" + username + ", password="
+ password + ", email=" + email + "]";
}
}
<?xml version="1.0" encoding="UTF-8"?>
<c3p0-config>
<default-config>
<property name="user">root</property>
<property name="password">root</property>
<property name="driverClass">com.mysql.jdbc.Driver</property>
<property name="jdbcUrl">jdbc:mysql:///web01</property>
</default-config>
</c3p0-config>