Java HashMap is not a thread-safe implementation of key-value storage, it doesn’t guarantee an order of keys as well. In the scope of this article, I’ll explain: HashMap internal implementation methods and functions and its performance (O(n) time complexity) collisions in HashMap interview questions and best practices Keep reading and use a table of contents … Read more
List is an interface for an ordered collection of elements in Java. You can easily add, remove and get elements by index. 2 main things that you should keep in mind using Lists in Java: Lists guarantee an order of elements. That means if you will add 1, 2, 3 integers to the list, you … Read more
First of all, let’s define what is an immutable object in Java. It’s one of the most popular interview questions. An immutable object is an object that constructed once and can’t be changed in future. How to create an immutable class in Java? You should follow rules: Make fields private and final. Make class final … Read more