黑马 web 课程 2023 版 SpringBoot 开发笔记

2025-09-14 14:33

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2025-09-14 14:33

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profile 动态激活，在不修改 yaml 文件的前提下更改项目环境 ![[Pasted image 20250909202302.png]]
运行 jar 包的方式： win 右键控制台运行
1. SpringBoot 能整合 Junit
2. SpringBoot 整合 mybatis
mybatis
1. mybatis 是持久层框架技术
2. property 文件配置数据库连接信息
3. 接口中定义集合，引入@mapper
4. Test 测试可以使用 Stream 流
SpringBoot 项目导入方法：文件-->打开（选择对应的crud文件夹）等打开后点开右边的Maven。点开文件夹双击install，就可以部署好项目。
数据库建表语句：

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-- 1) 建库（可按需改库名）
CREATE DATABASE IF NOT EXISTS `mybatis`
  DEFAULT CHARACTER SET utf8mb4
  COLLATE utf8mb4_unicode_ci;
USE `mybatis`;

-- 2) 建表（允许 job、dept_id、entrydate 为 NULL，以匹配第 17 行）
DROP TABLE IF EXISTS `emp`;
CREATE TABLE `emp` (
  `id`          BIGINT UNSIGNED NOT NULL AUTO_INCREMENT COMMENT '主键',
  `username`    VARCHAR(32)     NOT NULL COMMENT '登录名',
  `password`    VARCHAR(64)     NOT NULL COMMENT '密码',
  `name`        VARCHAR(32)     NOT NULL COMMENT '姓名',
  `gender`      TINYINT UNSIGNED NOT NULL COMMENT '1=男, 2=女',
  `image`       VARCHAR(64)     DEFAULT NULL COMMENT '头像文件名',
  `job`         TINYINT UNSIGNED DEFAULT NULL COMMENT '职位编号',
  `entrydate`   DATE            DEFAULT NULL COMMENT '入职日期',
  `dept_id`     BIGINT UNSIGNED DEFAULT NULL COMMENT '部门ID',
  `create_time` DATETIME        NOT NULL DEFAULT CURRENT_TIMESTAMP COMMENT '创建时间',
  PRIMARY KEY (`id`),
  UNIQUE KEY `uk_username` (`username`),
  KEY `idx_dept_id` (`dept_id`)
) ENGINE=InnoDB
  DEFAULT CHARSET = utf8mb4
  COLLATE = utf8mb4_unicode_ci;

-- 3) 插入 17 行示例数据（与截图对应）
INSERT INTO `emp`
(`id`,`username`,`password`,`name`,`gender`,`image`,`job`,`entrydate`,`dept_id`,`create_time`)
VALUES
(1,  'jinyong',      '123456','金庸',   1,'1.jpg',  4,'2000-01-01',2,'2022-11-07 09:11:00'),
(2,  'zhangwuji',    '123456','张无忌', 1,'2.jpg',  2,'2015-01-01',2,'2022-11-07 09:11:00'),
(3,  'yangxiao',     '123456','杨逍',   2,'3.jpg',  2,'2008-05-01',2,'2022-11-07 09:11:00'),
(4,  'weiyixiao',    '123456','韦一笑', 1,'4.jpg',  2,'2007-01-01',2,'2022-11-07 09:11:00'),
(5,  'changyuchun',  '123456','常遇春', 1,'5.jpg',  2,'2012-12-05',2,'2022-11-07 09:11:00'),
(6,  'xiaozhao',     '123456','小昭',   2,'6.jpg',  3,'2013-09-05',2,'2022-11-07 09:11:00'),
(7,  'jixiaofu',     '123456','纪晓芙', 2,'7.jpg',  1,'2005-08-01',1,'2022-11-07 09:11:00'),
(8,  'zhouzhiruo',   '123456','周芷若', 2,'8.jpg',  1,'2014-11-09',1,'2022-11-07 09:11:00'),
(9,  'dingminjun',   '123456','丁敏君', 2,'9.jpg',  1,'2011-03-11',1,'2022-11-07 09:11:00'),
(10, 'zhaomin',      '123456','赵敏',   2,'10.jpg', 1,'2013-09-05',1,'2022-11-07 09:11:00'),
(11, 'luzhangke',    '123456','鹿杖客', 1,'11.jpg', 5,'2007-02-01',3,'2022-11-07 09:11:00'),
(12, 'hebiweng',     '123456','鹤笔翁', 1,'12.jpg', 5,'2008-08-18',3,'2022-11-07 09:11:00'),
(13, 'fangdongbai',  '123456','方东白', 1,'13.jpg', 5,'2012-11-01',3,'2022-11-07 09:11:00'),
(14, 'zhangsanfeng', '123456','张三丰', 1,'14.jpg', 2,'2002-08-01',2,'2022-11-07 09:11:00'),
(15, 'yulianzhou',   '123456','俞连舟', 1,'15.jpg', 2,'2011-05-01',2,'2022-11-07 09:11:00'),
(16, 'songyuanqiao', '123456','宋远桥', 1,'16.jpg', 2,'2010-01-01',2,'2022-11-07 09:11:00'),
(17, 'chenyouliang', '123456','陈友谅', 1,'17.jpg', NULL,'2015-03-21',NULL,'2022-11-07 09:11:00');

-- 如需让后续自增从 18 开始：
ALTER TABLE `emp` AUTO_INCREMENT = 18;

Test 需要引入@Autowired
mybatis 占位符：#{}
接口文件引入@mapper和 sql 语法，引入相应注解（@Delete,@Insert）

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package com.example.demo.mapper;  
  
import org.apache.ibatis.annotations.Delete;  
import org.apache.ibatis.annotations.Mapper;  
  
@Mapper  
public interface EmpMapper {  
    @Delete("delete from emp where id = #{id}")  
    public int delete(Integer id);  
}

引入@Data,@Mapper注解

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package com.example.demo.pojo;  
  
import lombok.Data;  
import org.apache.ibatis.annotations.Mapper;  
  
@Data  
@Mapper  
public class Emp {  
    private Integer id;  
    private String username;  
    private String password;  
    private String gender;  
    private String email;  
  
    public Emp(String password, Integer id, String username, String gender, String email) {  
        this.password = password;  
        this.id = id;  
        this.username = username;  
        this.gender = gender;  
        this.email = email;  
    }  
  
    public String getEmail() {  
        return email;  
    }  
  
    public void setEmail(String email) {  
        this.email = email;  
    }  
  
    public String getGender() {  
        return gender;  
    }  
  
    public void setGender(String gender) {  
        this.gender = gender;  
    }  
  
    public String getPassword() {  
        return password;  
    }  
  
    public void setPassword(String password) {  
        this.password = password;  
    }  
  
    public String getUsername() {  
        return username;  
    }  
  
    public void setUsername(String username) {  
        this.username = username;  
    }  
  
    public Integer getId() {  
        return id;  
    }  
  
    public void setId(Integer id) {  
        this.id = id;  
    }  
  
    @Override  
    public String toString() {  
        return "EmpMapper{" +  
                "id=" + id +  
                ", username='" + username + '\'' +  
                ", password='" + password + '\'' +  
                ", gender='" + gender + '\'' +  
                ", email='" + email + '\'' +  
                '}';  
    }  
}

sql 需要防范 sql 注入，
mybatis 动态调用，需要传入参数，引入 mapper，注意占位符
1. 联动 mapper,Emp 文件，sql 文件，三个信息必须一致
2. 测试类需要构造员工对象
3. 主键返回：先获取ID，在保存相关联信息 ![[Pasted image 20250913172727.png]]
更新数据：@Update,卡点：sql 语句不熟悉
1. Mapper:动态调用查询语法
2. sql:查询语法
3. Test:构造员工对象
4. .property 文件管理控制台打印结果

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spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver  
spring.datasource.url=jdbc:mysql://127.0.0.1:3306/mybatis?useSSL=false&allowPublicKeyRetrieval=true&serverTimezone=UTC  
spring.datasource.username=root  
spring.datasource.password=  
# ????? ? ??  
mybatis.configuration.map-underscore-to-camel-case=true  
  
# 让 MyBatis 直接把 SQL/参数/执行结果打印到控制台  
mybatis.configuration.log-impl=org.apache.ibatis.logging.stdout.StdOutImpl  
  
#（可选）再把 mybatis 相关包的日志级别调高，保证都能看到  
logging.level.org.apache.ibatis=DEBUG  
logging.level.org.mybatis=DEBUG  
logging.level.com.example.demo.mapper=DEBUG  
  
# ???Hikari ???  
# spring.datasource.hikari.maximum-pool-size=10

数据查询：需要给 sql 封装对象起别名 ![[Pasted image 20250914111136.png]]
模糊查询，避免 sql 注入 ![[Pasted image 20250914120350.png]]https://www.bilibili.com/video/BV1m84y1w7Tb?t=37.2&p=129 [[mybatis sql 模糊查询案例]]
编写 xm 映射配置文件
1. 上官网查 mapper 接口权限类名
2. 简单的sql用注解，复杂的用xml配置 ![[Pasted image 20250914130703.png]] 3. xml 负责记录类名，sql 语句，对应文件名