Collections in Java

What are collections?
-Collections in Java is a framework that provides classes and interfaces to store and manipulate groups of objects dynamically.
-It is part of java.util package.

Why do we use collections?

Before collections:
-We used arrays.
-Arrays are fixed size.
-Cannot easily insert/delete elements.
**
After collections:**
-Dynamic size.
-Built-in methods.
-Better performance handling.

What is a collection? (Java Collection Framework)

• Collection is an interface.
• It is the root interface of List, Set, and Queue.
• Map is NOT a child of Collection.

Main Interfaces in collection:

• List.
• Set.
• Queue.
• Map.