-- 用戶表
CREATE TABLE `acc_user` (
  `id` bigint(20) NOT NULL AUTO_INCREMENT,
  `username` varchar(40) NOT NULL DEFAULT '' COMMENT '用戶名',
  `password` varchar(40) NOT NULL DEFAULT '' COMMENT '密碼',
  `create_by` varchar(80) DEFAULT NULL,
  `create_time` datetime DEFAULT CURRENT_TIMESTAMP,
  `update_by` varchar(80) DEFAULT NULL,
  `update_time` datetime DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;
-- 日志表
CREATE TABLE `modify_log` (
  `id` bigint(20) NOT NULL AUTO_INCREMENT,
  `action` varchar(20) NOT NULL DEFAULT '' COMMENT '操作',
  `entity_name` varchar(40) NOT NULL DEFAULT '' COMMENT '實體類名',
  `entity_key` varchar(20) DEFAULT NULL COMMENT '主鍵值',
  `entity_value` varchar(400) DEFAULT NULL COMMENT '實體值',
  `create_by` varchar(80) DEFAULT NULL,
  `create_time` datetime DEFAULT CURRENT_TIMESTAMP,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

@MappedSuperclass
@Getter @Setter
@MappedSuperclass
// 指定對應監(jiān)聽類
@EntityListeners(CreateListener.class)
public abstract class IdMapped {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    private String createBy;
    private Date createTime;
}

@Getter @Setter
@MappedSuperclass
// 指定對應監(jiān)聽類
@EntityListeners(EditListener.class)
public abstract class EditMapped extends IdMapped{
    private String updateBy;
    private Date updateTime;
}

@Entity
@Table(name = "acc_user")
@Getter @Setter
public class UserEntity extends EditMapped {
    private String username;
    private String password;
}

@Entity
@Table(name = "modify_log")
@Getter @Setter
public class ModifyLogEntity extends IdMapped{
    private String  action;
    private String  entityName;
    private String  entityKey;
    private String  entityValue;
}

public class CreateListener extends BasicListener {
    // 保存之前，為創(chuàng)建時間和創(chuàng)建人賦值
    @PrePersist
    public void prePersist(IdMapped idMapped) {
        if (Objects.isNull(idMapped.getCreateTime())) {
            idMapped.setCreateTime(new Date());
        }
        if (StringUtils.isBlank(idMapped.getCreateBy())) {
            // 根據(jù)鑒權系統(tǒng)實現(xiàn)獲取當前操作用戶，此處只做模擬
            idMapped.setCreateBy("test_create");
        }
    }
    // 保存之后，記錄變更日志
    @PostPersist
    public void postPersist(IdMapped idMapped) throws JsonProcessingException {
        recordLog(ACTION_INSERT, idMapped);
    }
}

public class EditListener extends BasicListener {
    // 修改之前，為修改人和修改時間賦值
    @PreUpdate
    public void preUpdate(EditMapped editMapped) {
        if (Objects.isNull(editMapped.getUpdateTime())) {
            editMapped.setCreateTime(new Date());
        }
        if (StringUtils.isBlank(editMapped.getUpdateBy())) {
            // 根據(jù)鑒權系統(tǒng)實現(xiàn)獲取當前操作用戶，此處只做模擬
            editMapped.setUpdateBy("test_update");
        }
    }
    // 修改之后，記錄變更日志
    @PostUpdate
    public void postUpdate(EditMapped editMapped) throws JsonProcessingException {
        recordLog(ACTION_UPDATE, editMapped);
    }
    // 刪除之前，記錄變更日志
    @PreRemove
    public void preRemove(EditMapped editMapped) throws JsonProcessingException {
        recordLog(ACTION_DELETE, editMapped);
    }
}

public class BasicListener implements ApplicationContextAware {
    private ApplicationContext applicationContext;
    protected static final String ACTION_INSERT = "insert";
    protected static final String ACTION_UPDATE = "update";
    protected static final String ACTION_DELETE = "delete";
    // 記錄變更日志
    protected void recordLog(String action, IdMapped object) throws JsonProcessingException {
        // 日志對象不需要再記錄變更日志
        if (object instanceof ModifyLogEntity) {
            return;
        }
        ModifyLogEntity modifyLogEntity = new ModifyLogEntity();
        modifyLogEntity.setAction(action);
        modifyLogEntity.setEntityKey(String.valueOf(object.getId()));
        modifyLogEntity.setEntityName(object.getClass().getSimpleName());
        // 對象轉(zhuǎn)json字符串存儲
        modifyLogEntity.setEntityValue(new ObjectMapper().writeValueAsString(object));
        Optional.ofNullable(applicationContext.getBean(ModifyLogDao.class))
                .ifPresent(modifyLogDao -> modifyLogDao.save(modifyLogEntity));
    }
    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        this.applicationContext = applicationContext;
    }
}

@Repository
public interface UserDao extends JpaRepository<UserEntity, Long> {
}

@Repository
public interface ModifyLogDao extends JpaRepository<ModifyLogEntity, Long> {
}

@Service
public class UserServiceImpl implements UserService {
    @Autowired
    private UserDao userDao;
    @Override
    @Transactional
    public void add(String userName, String password) {
        UserEntity userEntity = new UserEntity();
        userEntity.setUsername(userName);
        userEntity.setPassword(password);
        userDao.save(userEntity);
    }
    @Override
    @Transactional
    public void update(Long id, String password) {
        UserEntity userEntity = userDao.findById(id).orElseThrow(() -> new RuntimeException("用戶不存在"));
        userEntity.setPassword(password);
        userDao.save(userEntity);
    }
    @Override
    @Transactional
    public void delete(Long id) {
        UserEntity userEntity = userDao.findById(id).orElseThrow(() -> new RuntimeException("用戶不存在"));
        userDao.delete(userEntity);
    }
}

@SpringBootTest
public class SchoolApplicationTests {
    @Autowired
    private UserService userService;
    @Test
    public void testAdd() {
        userService.add("test1", "123456");
    }    
}

    @Test
    public void testUpdate() {
        userService.update(1L, "654321");
    }

	@Test
    public void testRemove() {
        userService.delete(1L);
    }