Eclipse（Java+Html+Jsp+Mysql）简易注册登录查询显示数据系统 JAVA部分（二）

文件目录结构：

具体介绍：

 JDBC连接数据库：

package com.edu.znjj.dao;import java.sql.Connection;import java.sql.DriverManager;import java.sql.SQLException;public class JDBC {private static String className = "com.mysql.jdbc.Driver";private static String url = "jdbc:mysql://localhost:3306/znjj?useSSL=true";private static String user = "root";private static String password = "123456";static{try {Class.forName(className);} catch (ClassNotFoundException e) {e.printStackTrace();}}public static Connection getConn() throws SQLException{Connection conn = DriverManager.getConnection(url, user, password);return conn;}public static void close(Connection conn){if(conn!=null){try {conn.close();} catch (SQLException e) {e.printStackTrace();}}}public static void main(String[] args) throws SQLException {Connection conn = getConn();System.out.println(conn);}}

USERDAO用户登录注册

package com.edu.znjj.dao;import java.sql.Connection;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.sql.SQLException;import com.edu.znjj.entity.User;public class UserDao {User user=null;     public User findByUser(String userName,String userPwd) throws SQLException{String sql = " SELECT id,username,userpwd,email,phone FROM t_user WHERE username=? AND userpwd=?";Connection conn = JDBC.getConn();PreparedStatement pstmt = conn.prepareStatement(sql);pstmt.setString(1, userName);pstmt.setString(2, userPwd);ResultSet rs = pstmt.executeQuery();if(rs.next()){user = new User();user.setId(rs.getInt("id"));user.setUserName(rs.getString("userName"));user.setUserPwd(rs.getString("userpwd"));user.setEmail(rs.getString("email"));user.setPhone(rs.getString("phone"));}JDBC.close(conn);return user;}    public void save(String userName,String userPwd,String email,String phone) throws SQLException{    String sql = "INSERT INTO t_user(username,userpwd,email,phone) VALUES(?,?,?,?)";    Connection conn = JDBC.getConn();    PreparedStatement pstmt = conn.prepareStatement(sql);    pstmt.setString(1, userName);    pstmt.setString(2, userPwd);    pstmt.setString(3, email);    pstmt.setString(4, phone);    pstmt.executeUpdate();    JDBC.close(conn);    }}

 XxDAO环境信息：

package com.edu.znjj.dao;import java.sql.Connection;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.sql.SQLException;import java.sql.Statement;import java.util.ArrayList;import java.util.List;import com.edu.znjj.entity.Xx;public class XxDao {public void save(String wd,String sd,String gz,int userId) throws SQLException{String sql= "INSERT INTO xx(wd,sd,gz,userid,created) VALUES(?,?,?,?,now())";Connection conn = JDBC.getConn();PreparedStatement pstmt = conn.prepareStatement(sql);pstmt.setString(1, wd);pstmt.setString(2, sd);pstmt.setString(3, gz);pstmt.setInt(4, userId);pstmt.executeUpdate();JDBC.close(conn);}public List findAll(Integer userId) throws SQLException{String sql = "SELECT id,wd,sd,gz,created,userid FROM xx WHERE USERID = ? ORDER BY created DESC";// 创建list集合对象List list = new ArrayList();Connection conn = JDBC.getConn();PreparedStatement pstmt = conn.prepareStatement(sql);pstmt.setInt(1, userId);ResultSet  rs = pstmt.executeQuery();while(rs.next()){Xx xx= new Xx();xx.setId(rs.getInt("id"));xx.setwd(rs.getString("wd"));xx.setsd(rs.getString("sd"));xx.setgz(rs.getString("gz"));xx.setUserId(rs.getInt("userId"));xx.setCreated(rs.getDate("created"));list.add(xx);}JDBC.close(conn);return list;}public void delete(Integer id) throws SQLException{String sql = "DELETE FROM xx WHERE id=?";Connection conn = JDBC.getConn();PreparedStatement pstmt = conn.prepareStatement(sql);pstmt.setInt(1, id);pstmt.executeUpdate();JDBC.close(conn);}public Xx findById(Integer id) throws SQLException{ String sql= "SELECT id,wd,sd,gz,userid,created FROM xx WHERE id=?";Xx xx = new Xx();Connection conn = JDBC.getConn();PreparedStatement pstmt = conn.prepareStatement(sql);pstmt.setInt(1, id);ResultSet rs = pstmt.executeQuery();rs.next();xx.setId(rs.getInt("id"));xx.setwd(rs.getString("wd"));xx.setsd(rs.getString("sd"));xx.setgz(rs.getString("gz"));xx.setUserId(rs.getInt("userId"));xx.setCreated(rs.getDate("created"));JDBC.close(conn);return xx;}public void update(Xx xx) throws SQLException{String sql = "UPDATE xx SET wd=?,sd=?,gz=?,created=NOW() WHERE id=?";Connection conn = JDBC.getConn();PreparedStatement pstmt = conn.prepareStatement(sql);pstmt.setString(1,xx.getwd());pstmt.setString(2,xx.getsd());pstmt.setString(3,xx.getgz());pstmt.setInt(4,xx.getId());pstmt.executeUpdate();JDBC.close(conn);}}

 user实体类：

package com.edu.znjj.entity;public class User {private Integer id;private String userName;private String userPwd;private String email;private String phone;public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public String getUserName() {return userName;}public void setUserName(String userName) {this.userName = userName;}public String getUserPwd() {return userPwd;}public void setUserPwd(String userPwd) {this.userPwd = userPwd;}public String getEmail() {return email;}public void setEmail(String email) {this.email = email;}public String getPhone() {return phone;}public void setPhone(String phone) {this.phone = phone;}}

 XX实体类：

package com.edu.znjj.entity;import java.sql.Date; public class Xx {   private Integer id;private String wd;private String sd;private String gz;private Date created;private Integer userId;public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public String getwd() {return wd;}public void setwd(String wd) {this.wd = wd;}public String getsd() {return sd;}public void setsd(String sd) {this.sd = sd;}public String getgz() {return gz;}public void setgz(String gz) {this.gz = gz;}public Date getCreated() {return created;}public void setCreated(Date created) {this.created = created;}public Integer getUserId() {return userId;}public void setUserId(Integer userId) {this.userId = userId;}}

 login主页servlet

package com.edu.znjj.Servlet;import java.io.IOException;import java.sql.SQLException;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 javax.servlet.http.HttpSession;import com.edu.znjj.dao.UserDao;import com.edu.znjj.entity.User;/** *用户登录 */@WebServlet("/login.do")public class LoginServlet extends HttpServlet {private static final long serialVersionUID = 1L;protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {String userName = request.getParameter("userName");String userPwd = request.getParameter("userpwd");//处理请求UserDao dao = new UserDao();try {User user = dao.findByUser(userName, userPwd);if(user !=null){HttpSession session = request.getSession();session.setAttribute("user",user);response.sendRedirect("main.html");}else{response.sendRedirect("error.html");}} catch (SQLException e) {e.printStackTrace();response.sendRedirect("login.html");}}}

 regist注册页：

package com.edu.znjj.Servlet;import java.io.IOException;import java.sql.SQLException;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 com.edu.znjj.dao.UserDao;@WebServlet("/regist.do")public class RegistServlet extends HttpServlet {private static final long serialVersionUID = 1L;protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {request.setCharacterEncoding("UTF-8");String username = request.getParameter("userName");//获取账号//输出账号System.out.println(username);String userpwd = request.getParameter("userpwd");//获取密码System.out.println(userpwd);String email = request.getParameter("email");//获取邮箱System.out.println(email);String phone = request.getParameter("phone");System.out.println(phone);//获取电话//将数据保存到数据库中，调用数据库代码UserDao dao = new UserDao();try {dao.save(username, userpwd, email, phone);} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();response.sendRedirect("error.html");}//创建一个对象，调用保存的方法//响应结果，url重定向到注册成功页面response.sendRedirect("registsuccess.html");}}

FindXX添加环境信息页

package com.edu.znjj.Servlet;import java.io.IOException;import java.sql.SQLException;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 javax.servlet.http.HttpSession;import com.edu.znjj.dao.XxDao;import com.edu.znjj.entity.User;/** *添加数据 */@WebServlet(name="/addxxServlet.do", urlPatterns = { "/addxxServlet.do" })public class AddXxServlet extends HttpServlet {private static final long serialVersionUID = 1L;protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { request.setCharacterEncoding("UTF-8");//中文化 //获取请求 String wd = request.getParameter("wd");//取标题 String sd = request.getParameter("sd");//取内容 String gz = request.getParameter("gz");//取内容 //获取登录用户ID HttpSession session = request.getSession(); User user = (User)session.getAttribute("user"); Integer userId = user.getId(); //处理请求 XxDao dao = new XxDao(); try {dao.save(wd, sd,gz, userId);response.sendRedirect("main.html");} catch (SQLException e) {e.printStackTrace();response.sendRedirect("error.html");} }}

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