[ShareMore] 2. Entity 작성

🔔 프로젝트를 시작하며 Entity를 작성합니다!

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지난 ERD 설계에 맞게 Entity를 구성해 줍니다!

📄 Users.java

@Getter
@AllArgsConstructor
@NoArgsConstructor(access = AccessLevel.PROTECTED)
@Entity
@Builder
public class Users {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long userId;

    private String name;

    private String email;

    private String password;

    private String address;
}

📄 Item.java

@Entity
@Builder
@Getter
@AllArgsConstructor
@NoArgsConstructor(access = AccessLevel.PROTECTED)
public class Item {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long itemId;

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "owner_id")
    private Users users;

    private String name;

    private String description;

    private String category;

    private int price;

}

📄 Reservation.java

@Entity
@Getter
@Builder
@AllArgsConstructor
@NoArgsConstructor(access = AccessLevel.PROTECTED)
public class Reservation {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long reservationId;

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "user_id")
    private Users userId;

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "item_id")
    private Users itemId;

    private LocalDateTime startDate;

    private LocalDateTime endDate;

}

📄 Review.java

@Entity
@Getter
@Builder
@AllArgsConstructor
@NoArgsConstructor(access = AccessLevel.PROTECTED)
public class Review {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long reviewId;

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "user_id")
    private Users userId;

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "item_id")
    private Item itemId;

    private String content;

    private int rating;
}

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BaseEntity

@MappedSuperclass
@EntityListeners(AuditingEntityListener.class)
@Getter
public abstract class BaseEntity {

    @CreatedDate
    private LocalDateTime createdAt;

    @LastModifiedDate
    private LocalDateTime updatedAt;
}

이것 처럼 모든 엔티티에 BaseEntity를 상속받게 해줍니다.

springboot에서도 자동으로 값을 바꿔주기 위해 어노테이션을 달아줍니다

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후 실행하면

쿼리가 콘솔에 찍힙니다!

그리고 h2 콘솔을 확인해주면

테이블들이 잘 생성된 것을 볼 수 있습니다!

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이제 세부설정 & 양방향 매핑을 해보겠습니다.

@Entity
@Getter
@Builder
@AllArgsConstructor
@NoArgsConstructor(access = AccessLevel.PROTECTED)
public class Reservation extends BaseEntity {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long reservationId;

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "user_id",nullable = false)
    private Users user;

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "item_id",nullable = false)
    private Item item;

    @Column(nullable = false)
    private LocalDateTime startDate;

    @Column(nullable = false)
    private LocalDateTime endDate;

}

@Entity
@Getter
@Builder
@AllArgsConstructor
@NoArgsConstructor(access = AccessLevel.PROTECTED)
public class Review extends BaseEntity {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long reviewId;

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "user_id", nullable = false)
    private Users user;

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "item_id", nullable = false)
    private Item item;

    @Column(nullable = true)
    private String comment;

    @Column(nullable = false)
    private int rating;
}

@Entity
@Builder
@Getter
@AllArgsConstructor
@NoArgsConstructor(access = AccessLevel.PROTECTED)
public class Item extends BaseEntity {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long itemId;

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "owner_id", nullable = false)
    private Users user;

    @Column(nullable = false)
    private String name;

    @Column(nullable = true)
    private String description;

    @Column(nullable = false)
    private String category;

    @Column(nullable = false)
    private int price;

    @OneToMany(mappedBy = "item", cascade = CascadeType.ALL)
    private List<Review> reviewList = new ArrayList<>();

    @OneToMany(mappedBy = "item", cascade = CascadeType.ALL)
    private List<Reservation> reservationList = new ArrayList<>();
}

@Getter
@AllArgsConstructor
@NoArgsConstructor(access = AccessLevel.PROTECTED)
@Entity
@Builder
public class Users extends BaseEntity {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long userId;

    @Column(nullable = false)
    private String name;

    @Column(nullable = false)
    private String email;

    @Column(nullable = false)
    private String password;

    @Column(nullable = false)
    private String address;

    @OneToMany(mappedBy = "user", cascade = CascadeType.ALL)
    private List<Item> itemList = new ArrayList<>();

    @OneToMany(mappedBy = "user", cascade = CascadeType.ALL)
    private List<Review> reviewList = new ArrayList<>();

    @OneToMany(mappedBy = "user", cascade = CascadeType.ALL)
    private List<Reservation> reservationList = new ArrayList<>();
}