Seems like an interesting effort. A developer is building an alternative Java-based backend to Lemmy's Rust-based one, with the goal of building in a handful of different features. The dev is looking at using this compatibility to migrate their instance over to the new platform, while allowing the community to use their apps of choice.

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[–] [email protected] 74 points 1 year ago (30 children)

Browsing the code makes me angry at how bloated Java projects are:

package com.sublinks.sublinksapi.community.repositories;

import com.sublinks.sublinksapi.community.dto.Community;
import com.sublinks.sublinksapi.community.models.CommunitySearchCriteria;
import com.sublinks.sublinksapi.post.dto.Post;
import com.sublinks.sublinksapi.post.models.PostSearchCriteria;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.Pageable;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.Query;
import org.springframework.data.repository.query.Param;
import java.util.List;

public interface CommunitySearchRepository {

  List allCommunitiesBySearchCriteria(CommunitySearchCriteria communitySearchCriteria);

}

Every file is 8 directories deep, has 20 imports, and one SQL statement embedded in a string literal. 😭

[–] Carighan 8 points 1 year ago (7 children)

And what's bad about that? As in, how is the verbosity a negative thing exactly? More so because virtually any tool can be configured to default-collapse these things if for your specific workflow you don't require the information.

At the same time, since everything is verbose, you can get very explicit information if you need it.

[–] [email protected] 15 points 1 year ago (3 children)

Here's an example:

https://github.com/sublinks/sublinks-api/blob/main/src/main/java/com/sublinks/sublinksapi/community/listeners/CommunityLinkPersonCommunityCreatedListener.java

IMO that's a lot of code (and a whole dedicated file) just to (magically) hook a global event and increase the subscriber count when a link object is added.

The worst part is that it's all copy/pasted into a neighbouring file which does the reverse:

https://github.com/sublinks/sublinks-api/blob/main/src/main/java/com/sublinks/sublinksapi/community/listeners/CommunityLinkPersonCommunityDeletedListener.java

It's not the end of the world or anything, I just think good code should surprise you with its simplicity. This surprises me with its complexity.

[–] BURN 3 points 1 year ago (1 children)

I find that Java is overly Verbose, but it’s much better than the alternative of underly verbose.

Java really follows the single class for single functionality principle, so in theory it makes sense to have these located in different classes. It should probably be abstracted to a shared method, but it shouldn’t be in the same file.

At least to me this looks like simplicity, but I’ve been writing Java in some capacity since 2012.

[–] [email protected] 6 points 1 year ago

It's not just the visible complexity in this one file. The point of it is to keep a subscriber count in sync, but you have that code I referenced above, plus:

LinkPersonCommunityCreatedEvent LinkPersonCommunityDeletedEvent LinkPersonCommunityCreatedPublisher LinkPersonCommunityDeletedPublisher

And then there are things like LinkPersonCommunityUpdated[Event/Publisher] which don't even seem to be used.

This is all boilerplate IMO.

And all of that only (currently) serves keeping that subscriber count up to date.

And then there's the hidden complexity of how things get wired up with spring.

And after all that it's still fragile because that event is not tied to object creation:

  @Transactional
  public void addLink(Person person, Community community, LinkPersonCommunityType type) {

    final LinkPersonCommunity newLink = LinkPersonCommunity.builder().community(community)
        .person(person).linkType(type).build();
    person.getLinkPersonCommunity().add(newLink);
    community.getLinkPersonCommunity().add(newLink);
    linkPersonCommunityRepository.save(newLink);
    linkPersonCommunityCreatedPublisher.publish(newLink);
  }

And there's some code here:

https://github.com/sublinks/sublinks-api/blob/main/src/main/java/com/sublinks/sublinksapi/api/lemmy/v3/community/controllers/CommunityOwnerController.java#L138C31-L138C50

    final Set linkPersonCommunities = new LinkedHashSet&lt;>();
    linkPersonCommunities.add(LinkPersonCommunity.builder().community(community).person(person)
        .linkType(LinkPersonCommunityType.owner).build());
    linkPersonCommunities.add(LinkPersonCommunity.builder().community(community).person(person)
        .linkType(LinkPersonCommunityType.follower).build());

    communityService.createCommunity(community);

    linkPersonCommunityRepository.saveAllAndFlush(linkPersonCommunities);

that is able to bypass the community link service and create links in the repository directly, which would presumably not trigger than event.

Maybe there's a good reason for that, but it sure looks fragile to me.

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