Sequenced Collections in Java - Deep Dive

This 45-minute conference talk from JavaOne 2025 explores the Sequenced Collections feature introduced in JDK 21, addressing a historical gap in the Java Collections Framework. Discover how these new collection types represent sequences with defined encounter order and provide uniform operations across collections. Learn about key capabilities including adding, retrieving, and removing elements from either end of collections, plus techniques for viewing, iterating, and streaming elements in reverse order. The presentation covers improvements to LinkedHashMap, the evolution of collection interface hierarchies, and practical demonstrations of how to leverage SequencedCollection, SequencedSet, and SequencedMap interfaces in your code. Presented by Stuart Marks, Consulting Member of Technical Staff in Oracle's Java Platform Group, this deep dive includes design rationales and future directions for Java collections.