Having Stream<Stream> how can we get the Stream that contains more elements in the other Stream

Question

I have 3 interfaces

public interface IGhOrg {
    int getId();

    String getLogin();

    String getName();

    String getLocation();

    Stream<IGhRepo> getRepos();
}

public interface IGhRepo {
    int getId();

    int getSize();

    int getWatchersCount();

    String getLanguage();

    Stream<IGhUser> getContributors();

}

public interface IGhUser {
    int getId();

    String getLogin();

    String getName();

    String getCompany();

    Stream<IGhOrg> getOrgs();
}

• I want to get Ighrepo with more users to contribute
  (Stream<IGhUser> getContributors())

Method signature:

Optional<IGhRepo> highestContributors(Stream<IGhOrg> organizations)

• What I’ve done to achieve the goal, but without success:

  Optional<IGhRepo> highestContributors(Stream<IGhOrg> organizations){
      return organizations
              .flatMap(IGhOrg::getRepos)
              .max((repo1,repo2)-> (int)repo1.getContributors().count() -(int)repo2.getContributors().count() );
  }
  

The result is this exception:

java.lang.Illegalstateexception: stream has already been operated upon or closed

NOTE: I understand that the count() is a terminal operation of the class Stream and that’s why you give me this exception.

I can’t solve this problem, please help.

Thank you.