1.加载驱动器、

2.创建connection对象、

3.创建Statement对象、

4.Statement(executeQuery方法)执行sql语句、

5.创建处理结果集对象ResultSet、

6.处理异常，关闭所有JDBC对象资源(注意关闭顺序与声明顺序相反，先关结果集对象、后关statement对象、最后关connection对象)。

/*

 Navicat Premium Data Transfer

 Source Server         : localhost-swp

 Source Server Type    : MySQL

 Source Server Version : 50730

 Source Host           : localhost:3306

 Source Schema         : project

 Target Server Type    : MySQL

 Target Server Version : 50730

 File Encoding         : 65001

 Date: 01/07/2022 16:36:16

*/

SET NAMES utf8mb4;

SET FOREIGN_KEY_CHECKS = 0;

-- ----------------------------

-- Table structure for sys_user

-- ----------------------------

DROP TABLE IF EXISTS `sys_user`;

CREATE TABLE `sys_user`  (

  `id` varchar(36) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NOT NULL COMMENT '主键ID',

  `username` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci DEFAULT NULL COMMENT '用户名',

  `password` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci DEFAULT NULL COMMENT '密码',

  `nickname` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci DEFAULT NULL COMMENT '昵称',

  `gender` int(1) DEFAULT 1 COMMENT '性别：0：女 1:男',

  `age` int(5) DEFAULT NULL COMMENT '年龄',

  `phone` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci DEFAULT NULL COMMENT '联系电话',

  `status` int(1) DEFAULT 0 COMMENT '状态：0：正常  1：禁用',

  `birthday` date DEFAULT NULL COMMENT '生日',

  `remark` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci DEFAULT NULL COMMENT '备注',

  PRIMARY KEY (`id`) USING BTREE

) ENGINE = InnoDB CHARACTER SET = utf8mb4 COLLATE = utf8mb4_general_ci ROW_FORMAT = Dynamic;

-- ----------------------------

-- Records of sys_user

-- ----------------------------

INSERT INTO `sys_user` VALUES ('1', 'swp', '123456', '宋伟朋', 1, 28, '18740458584', 0, '1992-05-07', '备注信息');

SET FOREIGN_KEY_CHECKS = 1;

 public static void main(String[] args) throws Exception {

        Connection con = null;

        Statement statement = null;

        ResultSet rs = null;

        try {

            // 连接数据库url信息

            String url = "jdbc:mysql://localhost:3306/project?useUnicode=true&characterEncoding=UTF8&zeroDateTimeBehavior=convertToNull&useSSL=false";

            // 用户名

            String username = "root";

            // 密码

            String password = "song@1234";

            // 1.加载驱动

            Class.forName("com.mysql.jdbc.Driver");

            // 2.连接数据库相当于数据库

            con = DriverManager.getConnection(url, username, password);

            // 3.向数据库发送sql的对象 Statement

            statement = con.createStatement();

            // 4.编写sql

            String sql = "select * from sys_user";

            // 5.执行sql

            rs = statement.executeQuery(sql);

            while (rs.next()){

                System.out.println("id："+rs.getObject("id"));

                System.out.println("username："+rs.getObject("username"));

                System.out.println("password："+rs.getObject("password"));

                System.out.println("nickname："+rs.getObject("nickname"));

                System.out.println("gender："+rs.getObject("gender"));

                System.out.println("age："+rs.getObject("age"));

                System.out.println("phone："+rs.getObject("phone"));

                System.out.println("status:"+rs.getObject("status"));

                System.out.println("birthday："+rs.getObject("birthday"));

                System.out.println("remark："+rs.getObject("remark"));

            }

        } catch (ClassNotFoundException | SQLException e) {

            e.printStackTrace();

        }finally {

            // 6.关闭连接，释放资源（一定要做） 先开后关

            rs.close();

            statement.close();

            con.close();

        }

    }