import java.util.ArrayList;
import java.util.Hashtable;
import java.util.List;
import java.util.function.BiFunction;

public class TestDnsProvider implements
        BiFunction<String, Hashtable<?,?>, List<String>>
{
    @Override
    public List<String> apply(String url, Hashtable<?, ?> env) {
        List<String> urls = new ArrayList<>();
        urls.add("ldap://yupyupyup:389");
        return urls;
    }
}