Collections in JAVA.
Collections in Java are part of the Java Collections Framework , which provides a set of classes and interfaces for storing and manipulating groups of objects. Collections simplify the handling of data structures like lists, sets, queues, and maps by offering ready-to-use methods for common operations such as searching, sorting, inserting, and deleting elements. Key Interfaces in the Java Collections Framework Collection : The root interface for all collection classes. Subinterfaces: List , Set , Queue , etc. List : Ordered collection of elements. Allows duplicate elements. Common implementations: ArrayList (dynamic array-based implementation). LinkedList (doubly linked list implementation). Vector (synchronized array-based implementation). Set : Collection that does not allow duplicate elements. Common implementations: HashSet (unordered, backed by a hash table). LinkedHashSet (maintains insertion order). TreeSet (sorted, backed by a red-black tree). Queue : Used to hold el...