Core Java Complete Notes By Durga Sir Top May 2026

This is where his notes become algorithmic. He doesn't just list that ArrayList is fast for retrieval. He shows the internal array, the grow() method, and the load factor of HashMap.

The crown jewel is his explanation of equals() and hashCode() contract. core java complete notes by durga sir top

"If two objects are equal according to equals(), their hashCode() must be equal. If two objects have the same hashCode(), they may not be equal." This is where his notes become algorithmic

His notes include the infamous "Bucket" diagram for HashMap. Once you visualize the bucket (array) and the linked list (chaining) inside the bucket, you never misuse a HashMap again. "If two objects are equal according to equals()

Most programming books teach you how to write code. Durga Sir’s notes teach you why the code works. The primary strength of this material lies in its deep dive into the internal mechanics of Java.

While others teach OOP in two pages, Durga Sir’s notes span 50+ pages on OOP alone, covering: