CODEWITHSUNDEEP
querydsl
Yura Heineken
Yura Heineken

Reputation: 255

QueryDsl and sets

I have 3 entities (User, Post, Comment):

@Entity
public class User {
    @Id  private Long id;
    @OneToMany private Set<Post> posts;
    ...
}

@Entity
public class Post {
    @Id  private Long id;
    @ManyToOne private User user;
    @OneToMany private Set<Comment> comments;
    ...
}

@Entity
public class Comment {
    @Id  private Long id;
    @ManyToOne private Post post;
    ...
}

Now I can select only users with posts:

List<User> users = query.from(qUser)
    .leftJoin(qUser.posts, qPost)
    .transform(groupBy(qUser.id).list(
        Projections.bean(User.class, qUser.id, ..., set(
            Projections.bean(Post.class, qPost.id, ...)
        ).as(qUser.posts))
    ));

But i need to select users with posts and with comments in one query, like:

List<User> users = query.from(qUser)
    .leftJoin(qUser.posts, qPost)
    .leftJoin(qPost.comments, qComment)
    .transform(groupBy(qUser.id).list(
        Projections.bean(User.class, qUser.id, ..., set(
            Projections.bean(Post.class, qPost.id, ...,
               set(Comment.class, qComment.id, ...).as(qPost,comments)
            )
        ).as(qUser.posts))
    ));

How can I do this?

Upvotes: 0

Views: 848

Answers (1)

Meiko Rachimow
Meiko Rachimow

Reputation: 4724

You need a third projection for your comments. 

List<User> users = query.from(qUser)
    .leftJoin(qUser.posts, qPost)
    .leftJoin(qPost.comments, qComment)
    .transform(groupBy(qUser.id).list(
        Projections.bean(User.class, qUser.id, ..., 
            set(Projections.bean(Post.class, qPost.id, ...,
               set(Projections.bean(Comment.class, qComment.id, ...).as("comments")
            ).as("posts")
        )
    );

Upvotes: 1

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