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部署项目、环境搭建
详细内容
1.导包
2.web >> index.jsp web >> login.jsp web >> success.jsp
1) web >> index.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %><html> <head> <title>$Title$</title> </head> <body> <a href="login.jsp">登录</a> </body></html>2) web >> login.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %><html lang="en"><head> <meta charset="UTF-8"> <title>登录</title> <style> #msg { color: red; } </style></head><body> <form action="user" method="post"> 账号：<input type="text" name="userName"><span id="msg"><%=request.getAttribute("msg")%></span> 密码：<input type="text" name="passWord"> <input type="hidden" name="method" value="login"> <input type="submit" value="登录"></form> </body></html>3) web >> success.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %><%@ page import="constant.Con" %><html><head> <title>用户中心</title></head><body><%=request.getSession().getAttribute(Con.USER)%><h2 >欢迎您</h2><a href="login.html">返回重新登录</a></body></html>constant >> Con
package constant; import java.io.Serializable; public class Con implements Serializable { //session中保存用户登录信息 public static final String USER = "user";}entity >> User
package entity; import java.io.Serializable; public class User implements Serializable { private int id; private String userName; private String passWord; public User(int id, String userName, String passWord) { this.id = id; this.userName = userName; this.passWord = passWord; } public User() { } 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; }}resources >> prop.properties
driverClassName=com.mysql.cj.jdbc.DriverurlName=jdbc:mysql://localhost:3306/myjdbc?characterEncoding=utf8&useSSL=false&serverTimezone=UTCuserName=rootpasswordName=root
5.utils >> JDBCUtils
package utils; import java.io.IOException;import java.io.InputStream;import java.sql.*;import java.util.Properties; public class JDBCUtils { // 声明驱动的路径 static String driverClass; static String url; static String user; static String password; static { // 创建属性集对象 Properties prop = new Properties(); // 将文件中的数据读取到属性集中 try { //prop.properties InputStream is = JDBCUtils.class.getClassLoader().getResourceAsStream("prop.properties"); prop.load(is); } catch (IOException e) { e.printStackTrace(); } // 获取key对应的value driverClass = prop.getProperty("driverClassName"); url = prop.getProperty("urlName"); user = prop.getProperty("userName"); password = prop.getProperty("passwordName"); try { // 加载驱动 Class.forName(driverClass); } catch (ClassNotFoundException e) { e.printStackTrace(); } } public static Connection getConnection() throws SQLException, ClassNotFoundException { // 获取连接 Connection connection = DriverManager.getConnection(url, user, password); return connection; } public static void close(Connection connection, Statement statement, ResultSet resultSet) { try { if (resultSet != null) { resultSet.close(); } } catch (SQLException e) { e.printStackTrace(); } // 调用已经实现功能的方法直接使用 close(connection, statement); } public static void close(Connection connection, Statement statement) { try { if (statement != null) { statement.close(); } } catch (SQLException e) { e.printStackTrace(); } try { if (connection != null) { connection.close(); } } catch (SQLException e) { e.printStackTrace(); } } }servlet >> UserServlet
package servlet; import constant.Con;import service.UserService;import service.impl.UserServiceImpl;import javax.servlet.ServletException;import javax.servlet.annotation.WebServlet;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import java.io.IOException; @WebServlet(name = "user", urlPatterns = "/user")public class UserServlet extends HttpServlet { private UserService userService = new UserServiceImpl(); @Override protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { //1.设置请求字符集为utf-8 req.setCharacterEncoding("utf-8"); //2.获取请求参数method,根据值调用不同方法处理业务 String method = req.getParameter("method"); if (method.equals("login")) { this.login(req, resp); } } //登录方法 private void login(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { //1.获取账号和密码 String userName = req.getParameter("userName"); String passWord = req.getParameter("passWord"); //2.调用service的方法处理登录 boolean result = userService.checkUser(userName, passWord); if (result) { //true表示登录成功 //转发跳转成功页面 //req.getRequestDispatcher("/success.jsp").forward(req, resp); //将用户信息保存在session域对象中 req.getSession().setAttribute(Con.USER, userName); //重定向跳转成功页面 resp.sendRedirect(req.getContextPath() + "/success.jsp"); } else { //false登录失败，返回登录页面 req.setAttribute("msg", "账号密码不匹配"); req.getRequestDispatcher("/login.jsp").forward(req, resp); } }}service >> UserService service >> impl >> UserServiceImpl
package service; public interface UserService { //判断登录成功与否 boolean checkUser(String userName, String passWord);}package service.impl; import dao.UserDao;import dao.impl.UserDaoImpl;import entity.User;import service.UserService;import utils.JDBCUtils;import java.sql.Connection;import java.util.List; public class UserServiceImpl implements UserService { private UserDao userDao = new UserDaoImpl(); @Override public boolean checkUser(String userName, String passWord) { // 连接对象 Connection connection = null; try { //1.获取数据库连接 connection = JDBCUtils.getConnection(); //2.调用dao方法查询数据 List<User> users = userDao.findUserByUserNameAndPassWord(connection, userName, passWord); //3.根据查询结果返回成功失败标志 if (users.size() > 0) { return true; } else { return false; } } catch (Exception e) { e.printStackTrace(); return false; } finally { JDBCUtils.close(connection, null); } }}dao >> UserDao dao >> impl >> UserDaoImpl
package dao; import entity.User;import java.sql.Connection;import java.util.List; public interface UserDao { //根据账号密码查询数据库，返回结果集 List<User> findUserByUserNameAndPassWord(Connection connection, String userName, String passWord);}package dao.impl; import dao.UserDao;import entity.User;import utils.JDBCUtils;import java.sql.Connection;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.util.ArrayList;import java.util.List; public class UserDaoImpl implements UserDao { @Override public List<User> findUserByUserNameAndPassWord(Connection connection, String userName, String passWord) { // 发送sql语句对象 PreparedStatement statement = null; List<User> userList = new ArrayList<>(); try { connection = JDBCUtils.getConnection(); // 获取Statement对象 statement = connection.prepareStatement("select * from user where username = ? and password = ?"); statement.setString(1, userName); statement.setString(2, passWord); ResultSet rs = statement.executeQuery(); while (rs.next()) { User user = new User(); int id = rs.getInt(1); String username = rs.getString(2); String password = rs.getString(3); user.setId(id); user.setUserName(username); user.setPassWord(password); userList.add(user); } return userList; } catch (Exception e) { e.printStackTrace(); return userList; } finally { JDBCUtils.close(null, statement, null); } }}登录实现
首页 index.jsp
错误登录 login.jsp
正确登录 login.jsp
4. 登录成功 success.jsp
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