Effective Java를 읽으며 코드 리펙토링

이펙티브자바의 목차

 

영어공부한다고 원서랑 번역본을 같이 보는중..

 

 

 

생성자 대신 팩토리 메서드를 고려해라

Item:  Consider static factory methods instead of constructors 

 

장점 1. 이름을 가질 수 있다. 

package com.everyparking.api.dto;

import lombok.Builder;
import lombok.Data;
import org.springframework.http.HttpStatus;

@Data
@Builder
public class DefaultResponseDtoEntity {

    private String message;
    private Object data;
    private HttpStatus httpStatus;
    
    private DefaultResponseDtoEntity() {}

    public static DefaultResponseDtoEntity of(HttpStatus httpStatus, String message) {
        return DefaultResponseDtoEntity
                .builder()
                .httpStatus(httpStatus)
                .message(message)
                .build();
    }

    public static DefaultResponseDtoEntity of(HttpStatus httpStatus, String message, Object data) {
        return DefaultResponseDtoEntity
                .builder()
                .httpStatus(httpStatus)
                .message(message)
                .data(data)
                .build();
    }

    public static DefaultResponseDtoEntity ok(String message) {
        return DefaultResponseDtoEntity
                .builder()
                .httpStatus(HttpStatus.OK)
                .message(message)
                .build();
    }

    public static DefaultResponseDtoEntity ok(String message, Object data) {
        return DefaultResponseDtoEntity
                .builder()
                .httpStatus(HttpStatus.OK)
                .message(message)
                .data(data)
                .build();
    }
}

 

 

장점 2. 생성할 때마다 인스턴스를 만들지 않아도된다. 

package com.everyparking.data.place.service;

import com.everyparking.api.dto.DefaultResponseDtoEntity;
import com.everyparking.api.dto.PlaceRequestDto;
import com.everyparking.data.place.domain.Place;
import com.everyparking.data.place.repository.PlaceRepository;
import com.everyparking.data.user.service.valid.JwtTokenUtils;
import lombok.RequiredArgsConstructor;
import org.springframework.http.HttpStatus;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

@Service
@RequiredArgsConstructor
@Transactional
public class PlaceService {

    private final PlaceRepository placeRepository;
    private final JwtTokenUtils jwtTokenUtils;

    public DefaultResponseDtoEntity addPlace(String token, PlaceRequestDto dto) {
        var user = jwtTokenUtils.getUserByToken(token);

        var data = placeRepository
                .save(Place.dtoToEntity(user,
                        dto.getPlaceName(),
                        dto.getMapAddr(),
                        dto.getMessage(),
                        dto.getMapX(),
                        dto.getMapY(),
                        dto.getImgUrl()));

        return DefaultResponseDtoEntity
                .of(HttpStatus.CREATED, "주차공간 등록 성공", data);
    }

    public DefaultResponseDtoEntity getAllPlace() {
        return DefaultResponseDtoEntity
                .ok("성공", placeRepository.findAll());
    }
}