Java Collections

Java from the very start has a clear motive of security and portability. And this language has not compromised with the same in any of their releases. But with time it has evolved from “just being another language” to “language for Software development” in nearly all the product companies. What kept Java alive from its beginning in 1995 to now till 2021 is modifications matching state-of-the-art technologies and rich set of libraries and modules to pursue nearly any code/task you wish a machine to perform.

What the tech companies are most “obsessed of” is the knowledge of Data Structures and Algorithms among their workers. Java provides set of libraries which have built-in interfaces for most of the data structures which can be used to do day-to-day tasks and put ideas to code in real-time.

Aim of this article is to talk of Collections module of Java which is full of interfaces and classes related to Stack, Queue, List, Heap, Sets and Maps as well. Believe me it will be of use to you to learn them all instead of writing the one yourself, when we generally don’t care of Generics in our code.

Collections Hierarchy

The hierarchy of classes and interfaces extending or implementing the Collection interface is shown below:-