duplicate result of criteria Api in join query using JpaSpecification - spring

Question

i am new to criteria api, so i have two models: GithubRepository and Issue where GithubReposity has many issue and every issue has one GithubRepository.
I have created many filters but the filter that did not work is the filter for GithubRepository where i want to check if a githubRepository has issues or Not.
after executing and applying has issues unfortunately something wrong happened and i see many duplicates.
here what i did in RepoSpecification:
public Specification<GithubRepository> getReposByIdIn(List<Long> iDs, String repoName) {
return (root, query, criteriaBuilder) -> {
List<Predicate> predicates = new ArrayList<>();
if (repoName != null && !repoName.isEmpty()) {
predicates.add(criteriaBuilder.like(criteriaBuilder.lower(root.get("repositoryName")),
"%" + repoName.toLowerCase() + "%"));
}
if (iDs != null && !iDs.isEmpty()) {
predicates.add( criteriaBuilder.in(root.get("id")).value(iDs) );
}
query.orderBy(criteriaBuilder.asc(root.get("repositoryName")));
return criteriaBuilder.and(predicates.toArray(new Predicate[0]));
};
}
public Specification<GithubRepository> getRepos(Boolean hasIssues,Boolean IsPrivate , String repoName) {
return (root, query, criteriaBuilder) -> {
List<Predicate> predicates = new ArrayList<>();
if (repoName != null && !repoName.isEmpty()) {
predicates.add(criteriaBuilder.like(criteriaBuilder.lower(root.get("repositoryName")),
"%" + repoName.toLowerCase() + "%"));
}
if ( hasIssues!= null && hasIssues.equals(true)) {
// JOINS INSTANCE
Join<GithubRepository, Issue> repoIssueJoin = root.join("issues");
//Predicate predicate = criteriaBuilder.equal(repoIssueJoin.get("githubRepository").get("repositoryName"),
repoName);
//predicates.add(criteriaBuilder.isNotNull(repoIssueJoin));
predicates.add(criteriaBuilder.equal(repoIssueJoin.get("githubRepository"),root));
}
if (IsPrivate != null && IsPrivate.equals(true)) {
predicates.add(criteriaBuilder.equal(root.get("isPrivate"), true));
}
query.orderBy(criteriaBuilder.asc(root.get("repositoryName")));
return criteriaBuilder.and(predicates.toArray(new Predicate[0]));
};
}
}
my problem is in here exactly:
if ( hasIssues!= null && hasIssues.equals(true)) {
// JOINS INSTANCE
Join<GithubRepository, Issue> repoIssueJoin = root.join("issues");
//Predicate predicate = criteriaBuilder.equal(repoIssueJoin.get("githubRepository").get("repositoryName"),
repoName);
//predicates.add(criteriaBuilder.isNotNull(repoIssueJoin));
predicates.add(criteriaBuilder.equal(repoIssueJoin.get("githubRepository"),root));
}
i do not know what is wrong exactly and how to fix the problem but i am stacked with it because i am planning to add a new filter to filter greatOrEqual by number of issues