<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>8.0.18</version>
</dependency>

package com.JDBC;
import java.sql.*;
public class JDBCTest {
    //1、加载驱动，固定写法!
//  private static final String DRIVER_NAME = "com.mysql.jdbc.Driver";//早期写法
    private static final String DRIVER_NAME = "com.mysql.cj.jdbc.Driver";

    //2、数据库连接信息
    private static final String URL = "jdbc:mysql://192.168.108.49:3306/echo?useUnicode=true&characterEncoding=UTF-8&useSSL=true";
    //用户名,更换成你自己的用户名，此处为root用户
    private static final String USER_NAME = "root";
    //密码，更换成你自己设定的密码，此处为:admin
    private static final String PASSWORD = "123456";
    public static void main(String[] args) throws ClassNotFoundException, SQLException {
            Connection connection = null;
            Class.forName(DRIVER_NAME);//加载mysql的驱动类

            //3、数据库连接
            connection = DriverManager.getConnection(URL, USER_NAME, PASSWORD);

            //4、生成一个真正执行SQL语句的对象：Statement
            Statement statement = connection.createStatement();

            //5、执行sql命令，获得返回结果
            String sql = "SELECT * FROM demo";
            ResultSet rs = statement.executeQuery(sql);//rs是查询出来的结果集，结果集封装了所有查询出来的东西
            while (rs.next()) {//输出结果
                System.out.println("--->:" + rs.getObject("name"));
            }

            //6、关闭连接
            rs.close();
            statement.close();
            connection.close();
    }

}