一个javaweb入门项目.zip

package com.fxy.dao; import java.util.ArrayList; import java.util.List; import com.fxy.model.Page; import com.fxy.model.User; /** * @author Memory * @date 2020-10-24 16:07:47 * 类说明 */ public class UserDao extends BaseDao{ /** * 用户登录 * @param userno 账号 * @param password 密码 * @return 用户对象，如果对象为空，则登陆失败，否则登陆成功。 */ public User login(String userno, String password) { //执行sql查询 String sql = "select * from t_user where userno='"+userno+"' and password='"+password+"'"; try { //1、获得连接 this.conn = this.getConn(); //2、获得执行命令对象 this.ps = conn.prepareStatement(sql); //3、执行查询命令 this.rs = ps.executeQuery(); //4、取出执行结果 while(rs.next()) {//如果有下一条 String name = rs.getString("name"); int userid = rs.getInt("user_id"); int age = rs.getInt("age"); String email = rs.getString("email"); String address = rs.getString("address"); User user = new User(); user.setAddress(address); user.setAge(age); user.setEmail(email); user.setName(name); user.setPassword(password); user.setUserno(userno); user.setUserid(userid); return user; } } catch (Exception e) { e.printStackTrace(); } return null; /* * 测试代码 //返回结果 User user = new User(); user.setAddress("山东青岛"); user.setAge(20); user.setEmail("125@qq.com"); user.setName("张三"); user.setPassword(password); user.setUserno(userno); return user; */ } /** * 查询用户列表 * @return */ public List<User> findUserList() { //执行sql查询 String sql = "select * from t_user"; try { //1、获得连接 this.conn = this.getConn(); //2、获得执行命令对象 this.ps = conn.prepareStatement(sql); //3、执行查询命令 this.rs = ps.executeQuery(); //4、取出执行结果 List<User> list = new ArrayList<User>(); while(rs.next()) {//如果有下一条 String name = rs.getString("name"); int userid = rs.getInt("user_id"); int age = rs.getInt("age"); String email = rs.getString("email"); String address = rs.getString("address"); String userno = rs.getString("userno"); String password = rs.getString("password"); User user = new User(); user.setAddress(address); user.setAge(age); user.setEmail(email); user.setName(name); user.setPassword(password); user.setUserno(userno); user.setUserid(userid); list.add(user); } return list; } catch (Exception e) { e.printStackTrace(); } return null; } /** * *搜索用户列表 * @return */ public List<User> findUserListByUserNo(String userno1) { //执行sql查询 String sql = "select * from t_user where userno like '%" + userno1 + "%'"; try { //1、获得连接 this.conn = this.getConn(); //2、获得执行命令对象 this.ps = conn.prepareStatement(sql); //3、执行查询命令 this.rs = ps.executeQuery(); //4、取出执行结果 List<User> list = new ArrayList<User>(); while(rs.next()) {//如果有下一条 String name = rs.getString("name"); int userid = rs.getInt("user_id"); int age = rs.getInt("age"); String email = rs.getString("email"); String address = rs.getString("address"); String userno = rs.getString("userno"); String password = rs.getString("password"); User user = new User(); user.setAddress(address); user.setAge(age); user.setEmail(email); user.setName(name); user.setPassword(password); user.setUserno(userno); user.setUserid(userid); list.add(user); } return list; } catch (Exception e) { e.printStackTrace(); } return null; } /** * 删除用户 * @param userid * @return */ public boolean deleteUser(String userid) { String sql = "delete from t_user where user_id="+userid; try { //1、获得连接 this.conn = this.getConn(); //2、获得执行命令对象 this.ps = conn.prepareStatement(sql); //3、执行删除、修改、新增命令 //result:数据库受影响的行数 int result = ps.executeUpdate();//成功或失败，true后false if(result>0) { //成功 return true; }else { //失败 return false; } } catch (Exception e) { e.printStackTrace(); } return true; } /** * 根据id查询用户信息 * @param userid * @return */ public User findUserById(String userid) { String sql = "select * from t_user where user_id=" + userid; try { //1、获得连接(连接数据库) this.conn = this.getConn(); //2、获得执行命令对象 this.ps = conn.prepareStatement(sql); //3、执行查询命令 this.rs = ps.executeQuery(); //4、取出执行结果 User user = null; if(rs.next()) {//如果有下一条 String name = rs.getString("name"); int age = rs.getInt("age"); String email = rs.getString("email"); String address = rs.getString("address"); String userno = rs.getString("userno"); String password = rs.getString("password"); user = new User(); user.setAddress(address); user.setAge(age); user.setEmail(email); user.setName(name); user.setPassword(password); user.setUserno(userno); user.setUserid(Integer.parseUnsignedInt(userid)); } return user; } catch (Exception e) { e.printStackTrace(); } return null; } /** * 修改用户 * @param user * @return */ public boolean updateUser(User user) { String sql = "update t_user set userno=?,`password`=?,`name`=?,age=? where user_id=?"; try { //1、获得连接 this.conn = this.getConn(); //2、获得执行命令对象 this.ps = conn.prepareStatement(sql); ps.setString(1, user.getUserno());//第一个问号 ps.setString(2, user.getPassword()); ps.setString(3, user.getName()); ps.setInt(4, user.getAge()); ps.setInt(5, user.getUserid()); //3、执行删除、修改、新增命令 //result:数据库受影响的行数 int result = ps.executeUpdate();//成功或失败，true后false if(result>0) { //成功 return true; }else { //失败 return false; } } catch (Exception e) { e.printStackTrace(); } return true; } /** * 新增用户 * @param user * @return */ public boolean addUser(User user) { String sql = "insert into t_user(userno,`password`,`name`,age) values(?,?,?,?)"; try { //1、获得连接 this.conn = this.getConn(); //2、获得执行命令对象 this.ps = conn.prepareStatement(sql); ps.setString(1, user.getUserno());//第一个问号 ps.setString(2, user.getPassword()); ps.setString(3, user.getName()); ps.setInt(4, user.getAge()); // ps.setString(5, user.getEmail()); // ps.setString(6, user.getAddress()); //3、执行删除、修改、新增命令 //result:数据库受影响的行数 int result = ps.executeUpdate();//成功或失败，true后false if(result>0) { //成功 return true; }else { //失败 return false; } } catch (Exception e) { e.printStackTrace(); } return true; } /** * 分页查询 * @param p * @return */ public List<User> findUserListByPage(Page p) { //执行sql查询 String sql = "select * from t_user limit ?,?"; try { //1、获得连接 this.conn = this.getConn(); //2、获得执行命令对象 this.ps = conn.prepareStatement(sql); ps.setInt(1, (p.getPage() - 1) * p.getPageSize());//第一个问号 ps.setInt(2, p.getPageSize());