keys.add(createFileKey(longitudeAndLatitude.longitude, longitudeAndLatitude.latitude));
}
Set<Fragment> fragments = new HashSet<>();
for (String key : keys) {
Fragment fragment = dataSource.getFragment(key);
if (fragment != null)
fragments.add(fragment);
}
Collection<Download> downloads = new HashSet<>();
for (Fragment<File> fragment : fragments) {
if (createFile(fragment.getKey()).exists())
continue;
downloads.add(download(fragment));
}
if (!downloads.isEmpty())