Personal study notes covering 39 Core Java topics with hands-on code examples. Special focus on Multithreading & Concurrency (13 dedicated topics) and Java 8+ features.
| # | Topic |
|---|---|
| 001 | Introduction to Java |
| 002 | How Java Works — JVM, JRE, JDK, Bytecode |
| 003 | Variables & Data Types |
| 004 | Methods |
| 005 | Constructor & Memory Management (Stack vs Heap) |
| 006 | Classes — Part 1 |
| 007 | Classes — Part 2 |
| 008 | Abstract Classes & Interfaces |
| 009 | Java 8 Interfaces — default & static methods |
| 010 | Reflections |
| 011 | Annotations |
| 012 | Exception Handling |
| 013 | Operators |
| 014 | Control Flow |
| # | Topic |
|---|---|
| 015 | Collections — Part 1 (List, Set, Queue) |
| 016 | Collections — Part 2 (Map, TreeMap, LinkedHashMap) |
| 017 | Streams API |
| # | Topic |
|---|---|
| 018 | Multithreading Introduction |
| 019 | Thread Creation & Methods |
| 020 | Race Conditions & Deadlocks |
| 021 | Thread Lifecycle, Monitor & Locks |
| 022 | Producer-Consumer Problem |
| 023 | Locks — Part 1 |
| 024 | Locks — Part 2 |
| 025 | Lock-Free Concurrency & Volatile |
| 026 | Thread Pool |
| 027 | Future & Callable |
| 028 | Other Pools (ForkJoin, ScheduledExecutor) |
| 029 | shutdown() vs awaitTermination() |
| 030 | Virtual Threads (Java 21) |
| # | Topic |
|---|---|
| 031 | Lombok |
| 032 | SequencedCollection, SequencedSet, SequencedMap |
| 034 | Serialization & Deserialization |
| 035 | Optionals |
| 036 | Method References |
| 037 | Generics & Wildcards |
| 038 | Relationships (Association, Aggregation, Composition) |
| 039 | Record Class & Marker Interface |
- 13 topics on Multithreading — from basics to Virtual Threads (Java 21)
- Lock-free concurrency & Volatile — rarely covered at this depth
- Java 8+ features — Streams, Optionals, Method References, default interfaces
- Modern Java — Records, Sequenced Collections, Virtual Threads
Mohit Kumar — Software Engineer @ Samsung SDS NIT Allahabad M.Tech | GATE 2020 — 98.68 percentile (Top 1%)
- 📨 EDA-Kafka — Event Driven Architecture
- 🏗️ LLD — Low Level Design patterns
- 🧪 Junit-Mockito — Testing notes