123/TeamInfoDal.java

package cn.fly.jdbc;

import cn.fly.entity.TeamInfo;

import java.io.IOException;
import java.sql.*;
import java.util.*;

public class TeamInfoDal {
    // 数据库连接字符串和相关属性
    private static final String DB_URL = "jdbc:mysql://localhost:3306/DBTeam";
    private static final String USER = "root";
    private static final String PASS = "20030815";

    // JDBC驱动名
    private static final String DRIVER = "com.mysql.cj.jdbc.Driver";

    // Connection对象
    private Connection conn;

    public static void main(String[] args) throws IOException {
        try {
            // 加载JDBC驱动
            Class.forName("com.mysql.cj.jdbc.Driver");
            // 建立数据库连接
            Connection conn = DriverManager.getConnection(DB_URL, USER, PASS);
            System.out.println("连接成功");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    // 构造函数
    public TeamInfoDal() {
        try {
            // 加载JDBC驱动
            Class.forName("com.mysql.cj.jdbc.Driver");
            // 建立数据库连接
            conn = DriverManager.getConnection(DB_URL, USER, PASS);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    // 添加报名信息
    public boolean addTeamInfo(TeamInfo teamInfo) {
        String sql = "INSERT INTO TeamInfo (id, sno, name, sex, tel) VALUES (?, ?, ?, ?, ?)";
        try (PreparedStatement stmt = conn.prepareStatement(sql)) {
            stmt.setString(1, teamInfo.getId());
            stmt.setString(2, teamInfo.getSno());
            stmt.setString(3, teamInfo.getName());
            stmt.setString(4, teamInfo.getSex());
            stmt.setString(5, teamInfo.getTel());
            // 执行插入操作并返回结果
            int rowsAffected = stmt.executeUpdate();
            return rowsAffected > 0;
        } catch (SQLException e) {
            e.printStackTrace();
            return false;
        }
    }

    // 修改报名信息
    public boolean updateTeamInfo(TeamInfo teamInfo) {
        String sql = "UPDATE TeamInfo SET sno=?, name=?, sex=?, tel=? WHERE id=?";
        try (PreparedStatement stmt = conn.prepareStatement(sql)) {
            stmt.setString(1, teamInfo.getSno());
            stmt.setString(2, teamInfo.getName());
            stmt.setString(3, teamInfo.getSex());
            stmt.setString(4, teamInfo.getTel());
            stmt.setString(5, teamInfo.getId());
            int rowsAffected = stmt.executeUpdate();
            return rowsAffected > 0;
        } catch (SQLException e) {
            e.printStackTrace();
            return false;
        }
    }

    // 删除报名信息
    public boolean deleteTeamInfo(String id) {
        String sql = "DELETE FROM TeamInfo WHERE id=?";
        try (PreparedStatement stmt = conn.prepareStatement(sql)) {
            stmt.setString(1, id);
            int rowsAffected = stmt.executeUpdate();
            return rowsAffected > 0;
        } catch (SQLException e) {
            e.printStackTrace();
            return false;
        }
    }

    // 根据id查询某条信息
    public TeamInfo getTeamInfoById(String id) {
        String sql = "SELECT * FROM TeamInfo WHERE id=?";
        TeamInfo teamInfo = null;
        try (PreparedStatement stmt = conn.prepareStatement(sql)) {
            stmt.setString(1, id);
            ResultSet rs = stmt.executeQuery();
            if (rs.next()) {
                teamInfo = new TeamInfo();
                teamInfo.setId(rs.getString("id"));
                teamInfo.setSno(rs.getString("sno"));
                teamInfo.setName(rs.getString("name"));
                teamInfo.setSex(rs.getString("sex"));
                teamInfo.setTel(rs.getString("tel"));
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return teamInfo;
    }

    // 查询所有数据
    public List<TeamInfo> getAllTeamInfos() {
        String sql = "SELECT * FROM TeamInfo";
        List<TeamInfo> list = new ArrayList<>();
        try (Statement stmt = conn.createStatement()) {
            ResultSet rs = stmt.executeQuery(sql);
            while (rs.next()) {
                TeamInfo teamInfo = new TeamInfo();
                teamInfo.setId(rs.getString("id"));
                teamInfo.setSno(rs.getString("sno"));
                teamInfo.setName(rs.getString("name"));
                teamInfo.setSex(rs.getString("sex"));
                teamInfo.setTel(rs.getString("tel"));
                list.add(teamInfo);
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }

        for (TeamInfo teamInfo : list) {
            System.out.println(teamInfo.toString());
        }

        return list;
    }

    // 关闭数据库连接
    public void close() {
        try {
            if (conn != null && !conn.isClosed()) {
                conn.close();
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}