持久层框架JPA之枚举值处理

DEMO实现枚举值的增查

1. entity

其中status字段为枚举类型，存入数据库的是对应的枚举值的值
StudentStatusEnum status缺点是枚举值可以为String和int类型，但是int类型会按照0开始，如果包含了枚举值为-1，或者乱序的情况无法处理，参考解决JPA的枚举局限性

@Data
@Entity
@NoArgsConstructor
@AllArgsConstructor
@Table(name = "student", indexes =
        {
                @Index(name = "idx_stu_no", columnList = "stu_no")
        }
)
public class Student {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "id", length = 20)
    @Comment("Primary Key, auto increment")
    private Long id;

    @Column(name = "stu_no", nullable = false, length = 20)
    @Comment("student number")
    private Long stuNo;

    @Column(name = "stu_name", nullable = false, length = 50)
    @Comment("student name")
    private String stuName;

    @Column(name = "age", nullable = false)
    @Comment("age")
    private Integer age;

    @Column(name = "last_execute_timestamp", nullable = false)
    @Comment("register date")
    private LocalDateTime registerDate;

    @Column(name = "status", nullable = false)
    @Comment("0: inactive, 1: active")
    private StudentStatusEnum status;
}

public enum StudentStatusEnum {
    INACTIVE(0),
    UNACTIVE(1);

    private final int code;

    StudentStatusEnum(final int code) {
        this.code = code;
    }

    public int getCode() {
        return this.code;
    }
}

repository

注意stu.status = com.user.common.enums.StudentStatusEnum.INACTIVE写法，之所以能这么写因为Entity中status字段为枚举类型。

@Repository
public interface StudentRepo extends JpaRepository<Student, Long>, PagingAndSortingRepository<Student, Long>, JpaSpecificationExecutor<Student> {

    @Query(value =
            "SELECT stu " +
            "FROM  Student stu " +
            "WHERE stu.status = com.user.common.enums.StudentStatusEnum.INACTIVE " +
            "   or (stu.status = com.user.common.enums.StudentStatusEnum.UNACTIVE)"
            )
    List<Student> getStudent1();
}

Test

// @Ignore
@DataJpaTest
@AutoConfigureTestDatabase(replace = AutoConfigureTestDatabase.Replace.NONE)
class StudentRepoTest extends Specification {
    @Autowired
    StudentRepo studentRepo


    @Commit
    def "save student"() {
        given:
        Student student = new Student()
        student.stuNo = 111L
        student.stuName = "neo"
        student.age = 18
        student.registerDate = LocalDateTime.now()
        student.status = StudentStatusEnum.INACTIVE



        when:
        def res = studentRepo.save(student)

        then:
        res.stuNo == 111L
    }

    def "get student"() {
        given:
        void

        when:
        def student = studentRepo.getStudent1();

        then:
        student.size() == 1
    }
}

application.yml

spring:
  jpa: #Jpa configuration. update or automatic table generation, console print sql
    database: mysql
    show-sql: true
    properties:
      hibernate:
        format_sql: true
        # generate_statistics: true
    hibernate:
      ddl-auto: update
      naming:
        implicit-strategy: org.hibernate.boot.model.naming.ImplicitNamingStrategyLegacyJpaImpl
        physical-strategy: org.hibernate.boot.model.naming.PhysicalNamingStrategyStandardImpl

数据库表

因为jpa配置了ddl-auto: update，所以执行单测时会自动创建表

CREATE TABLE `student` (
  `id` bigint NOT NULL AUTO_INCREMENT COMMENT 'Primary Key, auto increment',
  `age` int NOT NULL COMMENT 'age',
  `last_execute_timestamp` datetime(6) NOT NULL COMMENT 'register date',
  `status` int NOT NULL COMMENT '0: inactive, 1: active',
  `stu_no` bigint NOT NULL COMMENT 'student number',
  `stu_name` varchar(50) NOT NULL COMMENT 'student name',
  PRIMARY KEY (`id`),
  KEY `idx_stu_no` (`stu_no`)
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci

参考

【1】JPA遇到枚举类型：https://www.jianshu.com/p/9a4f0373bd19
【2】解决JPA的枚举局限性：https://www.cnblogs.com/xiaoq/p/7885775.html