package 建立连接;
import java.sql.*;
public class Conn {
    Connection con;
    public Connection getConnection() 
    {
        try {
            Class.forName("com.mysql.cj.jdbc.Driver");//加载数据库驱动类
            System.out.println("数据库驱动程序成功");
        }catch(ClassNotFoundException e){
            e.printStackTrace();
        }
        try {
            con=DriverManager.getConnection("jdbc:mysql://localhost:3306/my_text3?"
                    + "useUnicode=true&characterEncoding=utf8&characterSetResults=utf8","zhangzetao","545267257zzt");
            /*jdbc:mysql:// 是指JDBC连接方式；localhost: 是指你的本机地址；3306 ：SQL数据库的端口号；jdbc ：就是你要连接的数据库的地址。*/
            
            System.out.println("数据库连接成功");
        }catch(SQLException e) {
            e.printStackTrace();
        }
        return con; 
    }
    public static void main(String[] args) {
        Conn c = new Conn();//创建连接类对象
        Connection con=c.getConnection();//与数据库建立连接
        try {
            Statement sql=con.createStatement();//实例化Statement对象
            ResultSet res=sql.executeQuery("select * from user");//执行sql语句，返回结果集
            while(res.next()) {//通过next（）方法将指针指向下一行数据
                String id=res.getString("id");
                String name =res.getString("name");
                String password=res.getString("password");
                int points=res.getInt("points");
                System.out.print(id+" ");
                System.out.print(name+" ");
                System.out.print(password+" ");
                System.out.println(points);
            }
        }catch(SQLException e) {
            e.printStackTrace();
        }
    }
}