IDEA2023 SpringBoot整合MyBatis（三）

一、数据库表

CREATE TABLE students (id INT AUTO_INCREMENT PRIMARY KEY,name VARCHAR(100) NOT NULL,age INT,gender ENUM('Male', 'Female', 'Other'),email VARCHAR(100) UNIQUE,phone_number VARCHAR(20),address VARCHAR(255),date_of_birth DATE,enrollment_date DATE,course VARCHAR(100)
);-- 插入10条学生数据
INSERT INTO students (name, age, gender, email, phone_number, address, date_of_birth, enrollment_date, course) VALUES
('John Doe', 20, 'Male', '[e-mail]', '1234567890', '123 Main St, City', '2003-01-01', '2023-09-01', 'Computer Science'),
('Jane Smith', 21, 'Female', '[e-mail]', '0987654321', '456 Elm Rd, Town', '2002-02-02', '2023-09-01', 'Business Administration'),
('Michael Johnson', 19, 'Male', '[e-mail]', '1122334455', '789 Oak Ave, Village', '2004-03-03', '2023-09-01', 'Electrical Engineering'),
('Emily Davis', 22, 'Female', '[e-mail]', '5544332211', '321 Pine Blvd, County', '2001-04-04', '2023-09-01', 'Mechanical Engineering'),
('William Brown', 20, 'Male', '[e-mail]', '9988776655', '654 Cedar Ln, District', '2003-05-05', '2023-09-01', 'Civil Engineering'),
('Olivia Wilson', 21, 'Female', '[e-mail]', '4433221100', '987 Walnut St, Borough', '2002-06-06', '2023-09-01', 'Chemistry'),
('Benjamin Taylor', 19, 'Male', '[e-mail]', '7766554433', '246 Maple Dr, Neighborhood', '2004-07-07', '2023-09-01', 'Physics'),
('Grace Anderson', 22, 'Female', '[e-mail]', '3322110099', '852 Birch Rd, Hamlet', '2001-08-08', '2023-09-01', 'Mathematics'),
('Henry Thompson', 20, 'Male', '[e-mail]', '6655443322', '587 Aspen St, Province', '2003-09-09', '2023-09-01', 'Biology'),
('Chloe Robinson', 21, 'Female', '[e-mail]', '9977665544', '101 Poplar Ave, Region', '2002-10-10', '2023-09-01', 'Psychology');

二、在pom文件中添加MyBatis相关依赖包，Mysql驱动依赖

<dependencies><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-jdbc</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><!-- mybatis依赖 --><dependency><groupId>org.mybatis.spring.boot</groupId><artifactId>mybatis-spring-boot-starter</artifactId><version>3.0.3</version></dependency><!-- mysql依赖 --><dependency><groupId>com.mysql</groupId><artifactId>mysql-connector-j</artifactId><scope>runtime</scope></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope></dependency><!-- mybatis测试依赖 --><dependency><groupId>org.mybatis.spring.boot</groupId><artifactId>mybatis-spring-boot-starter-test</artifactId><version>3.0.3</version><scope>test</scope></dependency>

   当我们没有热部署的时候，我们必须在代码修改完后再重启程序，程序才会同步你修改的信息。那么我们可以手动启动热部署-》》》

     <!-- 热部署工具 --><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-devtools</artifactId><optional>true</optional></dependency>

 

三、编写实体类

public class Student {// 定义属性private String name; // 姓名private int age; // 年龄private String gender; // 性别private String email; // 邮箱private String phoneNumber; // 电话号码private String address; // 地址private java.util.Date dateOfBirth; // 出生日期private java.util.Date enrollmentDate; // 入学日期private String course; // 课程...setXXX and getXXX and constructor and toString...

四、 编写映射类StudentMapper

 */
@Mapper
public interface StudentMapper  {// @Select("select * from student where id = #{id}")public List<Student> findById(int id);//  @Select("select * from student")public List<Student> findAll();
}

注意：如果不写@Select注解，则就需要写Mapper映射文件

五、编写Mapper映射文件

  mybatis – MyBatis 3 | 配置

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.hlx.springbootdemo1.mapper.StudentMapper"><select id="findById" parameterType="int" resultType="Student">SELECT * FROM student WHERE id = #{id}</select><select id="findAll" resultType="Student">select * from student</select></mapper>

六、编写配置文件

#mysql数据源配置
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/school?useSSL=false&serverTimezone=UTC&allowPublicKeyRetrieval=true
spring.datasource.username=root
spring.datasource.password=123456#mybatis
mybatis.mapper-locations=classpath*:mapper/*.xml#实体类的别名
mybatis.type-aliases-package=com.hlx.springbootdemo1.entity#日志
logging.pattern.console='%d{HH:mm:ss.SSS} %clr(%-5level) ---  [%-15thread] %cyan(%-50logger{50}):%msg%n'

 七、编写业务类

@Service
public class StudentService {@Autowiredprivate StudentMapper studentMapper;public List<Student> findAll(){return (studentMapper.findAll());}public Student findById(int id){return (studentMapper.findById(id));}
}

 八、编写控制器类

@RestController
public class StudentsController {@Autowiredprivate StudentService studentService;@GetMapping("/user/{id}")public Student findById(@PathVariable int id) {return studentService.findById(id);}@GetMapping("/user/all")public List<Student> findAll() {return studentService.findAll();}
}

九、启动类

@SpringBootApplication
@MapperScan("com.hlx.springbootdemo1.mapper")
public class SpringbootDemo1Application {public static void main(String[] args) {SpringApplication.run(SpringbootDemo1Application.class, args);}}

十、项目结构

十一、启动运行