@RestController
public class TestController {

    @GetMapping("convert")
    public Object convertEntity() {
        User user = User.builder()
                .id(1)
                .name("张三")
                .createTime("2020-04-01 11:05:07")
                .updateTime(LocalDateTime.now())
                .build();
        List<Object> objectList = new ArrayList<>();

        objectList.add(user);

        // 使用mapstruct
        UserVO1 userVO1 = UserCovertBasic.INSTANCE.toConvertVO1(user);
        objectList.add("userVO1:" + UserCovertBasic.INSTANCE.toConvertVO1(user));
        objectList.add("userVO1转换回实体类user:" + UserCovertBasic.INSTANCE.fromConvertEntity1(userVO1));
        // 输出转换结果
        objectList.add("userVO2:" + " | " + UserCovertBasic.INSTANCE.toConvertVO2(user));
        // 使用BeanUtils
        UserVO2 userVO22 = new UserVO2();
        BeanUtils.copyProperties(user, userVO22);
        objectList.add("userVO22:" + " | " + userVO22);

        return objectList;
    }
}

@Component
public class UserCovertBasicImpl implements UserCovertBasic {
    public UserCovertBasicImpl() {
    }

    public UserVO1 toConvertVO1(User source) {
        if (source == null) {
            return null;
        } else {
            UserVO1 userVO1 = new UserVO1();
            userVO1.setId(source.getId());
            userVO1.setName(source.getName());
            userVO1.setCreateTime(source.getCreateTime());
            userVO1.setUpdateTime(source.getUpdateTime());
            return userVO1;
        }
    }

    public User fromConvertEntity1(UserVO1 userVO1) {
        if (userVO1 == null) {
            return null;
        } else {
            User user = new User();
            user.setId(userVO1.getId());
            user.setName(userVO1.getName());
            user.setCreateTime(userVO1.getCreateTime());
            user.setUpdateTime(userVO1.getUpdateTime());
            return user;
        }
    }

    public UserVO2 toConvertVO2(User source) {
        if (source == null) {
            return null;
        } else {
            UserVO2 userVO2 = new UserVO2();
            userVO2.setId(source.getId());
            userVO2.setName(source.getName());
            userVO2.setCreateTime(source.getCreateTime());
            return userVO2;
        }
    }
}