Introduction to Sequenced Collections in Java 21

The Collections Framework in Java forms the basis for representing data structures and algorithms. The collections framework provides types for collections of objects - sets, maps, lists, etc. Sequenced collections in Java 21 refurbish the collections framework by adding the notion of sequence in elements of a collection. Sequenced collections provide an encounter order to elements of a collection. Sequenced collections are implemented pervasively in the collections framework.

The book introduces sequenced collections as a new language feature in Java 21.