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JavaBeginner#collections#list
JavaIntermediate#collections
Explain the Collections framework hierarchy.
Iterable → Collection → List (ArrayList, LinkedList), Set (HashSet, TreeSet, LinkedHashSet), Queue (PriorityQueue, Deque). Map is separate: HashMap, LinkedHashMap, TreeMap, ConcurrentHashMap.
Example
List<String> list = new ArrayList<>(); Set<String> set = new TreeSet<>(); Map<String,Integer> map = new HashMap<>();