Object-Oriented Programming & Java Essentials
This section builds a strong foundation in object-oriented programming (OOP) and Java essentials.
It covers both the theory (OOP principles, UML modeling) and the practical Java topics most commonly asked in interviews, ensuring you can explain concepts clearly and apply them in real-world coding challenges.
Topics Covered
1. OOP Fundamentals
- Overview
- Encapsulation: hiding implementation details.
- Abstraction: focusing on relevant details, ignoring noise.
- Abstraction vs Encapsulation
- Inheritance: reusing code via IS-A relationships.
- Polymorphism: interchangeable behavior with interfaces and abstract classes.
3. Java Multithreading & Concurrency
- Overview
- Thread Basics
- Synchronization & Thread Safety
- Executor Framework
- Concurrency Utilities in Java
- Advanced Topics in Java Concurrency
- Java Concurrency - Interview & Real-World Scenarios
4. Locks & Synchronization in Java
- Synchronization Basics
- Explicit Locks in Java — ReentrantLock
- Read-Write & Stamped Locks
- Advanced Locking & Patterns in Java
- High-Level Abstractions vs Locks in Java
5. Memory Management & Garbage Collection
- Java Memory Model Basics
- Garbage Collection Fundamentals in Java
- Garbage Collection Algorithms
- GC Implementations in HotSpot JVM
- Tuning & Monitoring Garbage Collection in JVM
- Advanced GC Topics in Java
6. Exceptions & Error Handling
7. Immutability
8. Collections & Hashing
9. Java 8+ Features (Lambdas, Streams, Optional)
A focused mini-series on core Java 8+ features — each page is standalone and interview-focused.
Why This Section Matters
- For Interviews: OOP basics + Java concurrency, memory management, and collections are staples in FAANG-level interviews.
- For Real-World Engineering: Writing clean, maintainable, and scalable Java systems requires deep understanding of these concepts.
- For System Design: OOP and Java fundamentals underpin higher-level design principles, patterns, and architectures.
Next
Start with Encapsulation.