🌱Spring/LOMBOK:: @NOARGSCONSTRUCTOR , @ALLARGSCONSTRUCTOR , @REQUIREDARGSCONSTRUCTOR / DI

LOMBOK Constructor Injection

@NoArgsConstructor	파라미터가 없는 기본 생성자를 생성(기본 생성자)
@AllArgsConstructor	모든 필드 값을 파라미터로 받는 생성자를 만듦(모든 필드의 생성자)
@RequiredArgsConstructor	final이나 @NonNull인 필드 값만 파라미터로 받는 생성자 만듦(필수 생성자)

 

@NoArgsConstructor

@NoArgsConstructor
public class BookWithLombok {

    private Long id;
    private String isbn;
    private String name;
    private String author;
}

 

public class BookWithOutLombok {

    private Long id;
    private String isbn;
    private String name;
    private String author;

    public BookWithOutLombok() {

    }
}

 

@AllArgsConstructor

@AllArgsConstructor
public class BookWithLombok {

    private Long id;
    private String isbn;
    private String name;
    private String author;
    private boolean useYn;
}

public class BookWithLombok {
    private Long id;
    private String isbn;
    private String name;
    private String author;
    private boolean useYn;

    public BookWithLombok(final Long id, final String isbn, final String name, final String author, final boolean useYn) {
        this.id = id;
        this.isbn = isbn;
        this.name = name;
        this.author = author;
        this.useYn = useYn;
    }
}

 

@RequiredArgsConstructor

@RequiredArgsConstructor
public class BookWithLombok {

    private final Long id;
    private final String isbn;
    private final String name;
    private final String author;
    private boolean useYn;
}

public class BookWithLombok {
    private final Long id;
    private final String isbn;
    private final String name;
    private final String author;
    private boolean useYn;

    public BookWithLombok(final Long id, final String isbn, final String name, final String author) {
        this.id = id;
        this.isbn = isbn;
        this.name = name;
        this.author = author;
    }
}

 

 

Usage Example

@NoArgsConstructor
@RequiredArgsConstructor
@AllArgsConstructor
public class User {

  private Long id;
  
  @NonNull
  private String name;
  
  @NonNull
  private String pw;
  
  private int age;
  
}

User user1 = new User(); // @NoArgsConstructor
User user2 = new User("user2", "1234"); // @RequiredArgsConstructor
User user3 = new User(1L, "user3", "1234", null); // @AllArgsConstructor

 

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LOMBOK DI

롬복 적용 전

import org.springframework.stereotype.Service;

@Service
public class TestService {

    private final TestRepository testRepository;

    public TestService(TestRepository testRepository) {
        this.testRepository = testRepository;
    }
}

 

롬복 적용 후

import lombok.RequiredArgsConstructor;
import org.springframework.stereotype.Service;

@Service
@RequiredArgsConstructor
public class TestService {

    private final TestRepository testRepository;
}

 

 

 

 

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Reference
- Constructor Injection:
https://lovethefeel.tistory.com/71