all sorts of things

2-Application/src/main/java/category/CategoryUseCase.java

@@ -7,7 +7,7 @@ public class CategoryUseCase {
 	private final CategoryRepository categoryRepository;
 	private final CategoryIdGenerator categoryIdGenerator;
 
-	CategoryUseCase(final CategoryRepository categoryRepository, final CategoryIdGenerator idGenerator) {
+	public CategoryUseCase(final CategoryRepository categoryRepository, final CategoryIdGenerator idGenerator) {
 		this.categoryRepository = categoryRepository;
 		this.categoryIdGenerator = idGenerator;
 	}

2-Application/src/main/java/link/LinkDto.java

@@ -0,0 +1,11 @@
+package link;
+
+import category.Category;
+import tag.Tag;
+import user.Username;
+
+import java.util.Set;
+
+public record LinkDto(Username creator, LinkUrl url, Set<Category> categories, Set<Tag> tags) {
+
+}

2-Application/src/main/java/link/LinkUseCase.java

@@ -2,6 +2,7 @@ package link;
 
 import category.CategoryName;
 import category.CategoryRepository;
+import exeptions.CategroyDoesNotExist;
 import exeptions.URLIsNotReachable;
 import tag.TaggingUseCase;
 import user.Username;
@@ -43,4 +44,20 @@ public class LinkUseCase {
 		linkRepository.add(link);
 	}
 
+	public Set<LinkDto> getLinks() {
+		return linkRepository
+				.getAll()
+				.stream()
+				.map(link -> new LinkDto(link.getCreator(),
+				                         link.getUrl(),
+				                         link
+						                         .getCategoryIds()
+						                         .stream()
+						                         .map(categoryRepository::getById)
+						                         .map(optional -> optional.orElseThrow(() -> new CategroyDoesNotExist(
+								                         "A Category for a certain id does not exits. You must create it first.")))
+						                         .collect(Collectors.toSet()),
+				                         link.getTags()))
+				.collect(Collectors.toSet());
+	}
 }

2-Application/src/main/java/tag/TaggingUseCase.java

@@ -1,19 +1,21 @@
 package tag;
 
 import link.LinkUrl;
+import link.RandomLinkIdGenerator;
 
+import java.util.HashSet;
 import java.util.Set;
 
 public class TaggingUseCase {
 
 	TagMatcherRepository tagMatcherRepository;
 
-	public TaggingUseCase(TagMatcherRepository tagMatcherRepository) {
+	public TaggingUseCase(TagMatcherRepository tagMatcherRepository, RandomLinkIdGenerator randomLinkIdGenerator) {
 		this.tagMatcherRepository = tagMatcherRepository;
 	}
 
 	public Set<Tag> getTagsFor(LinkUrl url) {
-		Set<Tag> result = Set.of();
+		Set<Tag> result = new HashSet<>();
 		tagMatcherRepository.getTagMatchers().forEach(tagMatcher -> tagMatcher.ifMatches(url).addTo(result));
 		return result;
 	}