Q25: What is the high-level architecture of the Java Collections Framework?
Rooted at java.util.Collection (for single elements) and java.util.Map (for key-value pairs):
Collection:List: Ordered, allows duplicates (ArrayList,LinkedList,Vector).Set: Unordered, unique elements (HashSet,LinkedHashSet,TreeSet).Queue/Deque: Element processing order (PriorityQueue,ArrayDeque).
Map(Separate Hierarchy): Key-value mapping (HashMap,LinkedHashMap,TreeMap,ConcurrentHashMap).
Key Takeaways
Mapdoes NOT extendCollection.Listmaintains insertion order;Setenforces element uniqueness.
Knowledge Check
Which core collection interface does java.util.Map extend?