AtticCollectionsUtilities & Concurrency
Overview
Static algorithms, immutable factory methods, scalable concurrency, and specialized bit/enum collections
Beyond the standard collection classes, the Java platform provides polymorphic static algorithms, factory methods for unmodifiable collections, and high-performance concurrent collections in java.util.concurrent.
Roadmap
Detailed Guides
Collections Helper Class
Polymorphic sorting, shuffling, unmodifiable wrappers, and immutable List.of/Set.of/Map.of factories
Concurrent Collections
ConcurrentHashMap lock striping, CopyOnWriteArrayList snapshot iteration, and obsolete Hashtable
Specialized Types & Autoboxing
EnumSet bit vectors, EnumMap, BitSet flag packing, and avoiding autoboxing overhead in hot loops