void (String[] args) { Collection unmodifiableCollection = getEmptyList(); List unmodifiableList = getEmptyList(); Set unmodifiableSet = getEmptySet(); Map unmodifiableMap = getEmptyMap(); SortedSet unmodifiableSortedSet = getEmptySet(); SortedMap unmodifiableSortedMap = getEmptyMap(); NavigableSet unmodifiableNavigableSet = getEmptySet(); NavigableMap unmodifiableNavigableMap = getEmptyMap(); }