Explore Topics

Select a topic to dive in. These notes are structured to be read linearly or used as a reference.

☕ Core Java

Foundational concepts required for every Java developer.

OOP Concepts

Classes, Objects, Inheritance, Polymorphism, Abstraction, Encapsulation.

Exception Handling

Try-catch, finally, throw vs throws, custom exceptions.

String Handling

Understanding String immutability, the String Pool, StringBuilder, and StringBuffer.

📚 Java Collections

Data structures and utilities for managing groups of objects.

Collections Framework

List, Set, Map, Queue, Deque interfaces and implementations.

Generics

Type parameters, bounded types, wildcards.

Streams API

Functional programming, map, filter, reduce, collectors.

🚀 Advanced Topics

In-depth concepts for experienced Java developers.

Concurrency

Threads, Synchronization, Executors, Concurrent Collections.

Multithreading

Thread Lifecycle, Runnable, Callable, Thread Pools.

Java Memory Model

Heap vs Stack, Object Lifecycle, Memory Leaks.

🛠️ Patterns

A collection of proven solutions for architecture, enterprise systems, and algorithmic problem solving.

Design Patterns

Creational, Structural, and Behavioral patterns (Singleton, Factory, Observer).

J2EE Patterns

Enterprise architectures like MVC, DAO, DTO, and Front Controller.

Algorithm Patterns

Interview strategies like Sliding Window, Two Pointers, and Merge Intervals.