Spring Boot引入Spring Data JPA

引入依赖

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<!-- https://mvnrepository.com/artifact/com.alibaba/druid -->
<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>druid</artifactId>
    <version>1.2.8</version>
</dependency>

application.yml

server:
  port: 80
  servlet:
    context-path: /
  tomcat:
    uri-encoding: UTF-8

# 数据源配置
spring:
  application:
    name: microservice-student
  datasource:
    type: com.alibaba.druid.pool.DruidDataSource
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://localhost:3306/db_bookmanagesystem?useUnicode=true&characterEncoding=UTF-8&serverTimezone=UTC
    username: root
    password: 123456
  jpa:
    hibernate:
      ddl-auto: update
      naming:
        physical-strategy: org.hibernate.boot.model.naming.PhysicalNamingStrategyStandardImpl #配置后可以通过@Column注解的name属性自定义数据库的字段名称
    show-sql: true

实体类

使用了lombok，如果不想使用就自行生成setter和getter方法

package com.ledao.entity;

import lombok.Data;

import javax.persistence.*;

/**
 * 用户实体类
 *
 * @author LeDao
 * @company
 * @create 2022-01-21 16:26
 */
@Data
@Entity
@Table(name = "t_user")
public class User {

    /**
     * 编号
     */
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Integer id;
    /**
     * 用户名
     */
    @Column(name = "userName", length = 100)
    private String userName;
    /**
     * 昵称
     */
    @Column(name = "nickName", length = 100)
    private String nickName;
    /**
     * 密码
     */
    @Column(length = 100)
    private String password;
    /**
     * 用户类型,1代表管理员,2代表普通用户
     */
    private Integer type;
    /**
     * 用户状态,1代表正常,2代表被封禁
     */
    private Integer state;
    /**
     * 是否可借书
     */
    @Column(name = "isBorrow")
    private Integer isBorrow;
}

Repository接口

package com.ledao.repository;

import com.ledao.entity.User;
import org.springframework.data.jpa.repository.JpaRepository;

/**
 * 用户Repository接口
 *
 * @author LeDao
 * @company
 * @create 2022-01-21 17:01
 */
public interface UserRepository extends JpaRepository<User, Long> {
}

测试

package com.ledao;

import com.ledao.entity.User;
import com.ledao.repository.UserRepository;
import org.junit.jupiter.api.Test;
import org.springframework.boot.test.context.SpringBootTest;

import javax.annotation.Resource;

@SpringBootTest
class BookManageSystemApplicationTests {

    @Resource
    private UserRepository userRepository;

    @Test
    void contextLoads() {
        User user = new User();
        user.setUserName("admin");
        user.setNickName("乐道");
        user.setPassword("admin");
        user.setType(1);
        user.setState(1);
        user.setIsBorrow(1);
        userRepository.save(user);
    }

}

结果

如果数据库的t_user表中新增了一条记录，说明引入Spring Data JPA成功