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Java Collections Framework hierarchy with Iterable, Collection, List, Set, Queue, Deque, Map and the Java 21 SequencedCollection, SequencedSet and SequencedMap interfaces

Java Collections & Arrays Tutorial

Learn the Java Collections Framework with a Java 21 hierarchy diagram, how to choose List, Set, Map and Queue classes, and links to every tutorial.

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HowToDoInJava provides tutorials and how-to guides on Java and related technologies.

It also shares the best practices, algorithms & solutions and frequently asked interview questions.