Java Study Guide

Overview

This repository is a structured, day-by-day study guide designed to help learners
build a strong foundation in Java, progressing from basic concepts to advanced
topics and real-world backend development practices.

Each day includes:
- Concept explanation (Markdown)
- Real-life examples
- Simple pseudo code
- Java implementation files

Goal:
To provide a clear, practical, and industry-relevant learning path for mastering Java.

Study Plan

Phase 1: Foundations

Day 1  : Introduction to Java and OOP Concepts
Day 2  : Variables, Data Types, and Operators
Day 3  : Control Flow (if-else, switch, loops)
Day 4  : Methods and Functions
Day 5  : Arrays (1D and 2D)
Day 6  : Strings and String Handling
Day 7  : Memory Basics (Stack vs Heap, Pass by Value)

Phase 2: Core OOP and Java Essentials

Day 8  : Classes and Objects Deep Dive
Day 9  : Constructors in Java
Day 10 : Encapsulation
Day 11 : Inheritance
Day 12 : Polymorphism (Compile-time and Runtime)
Day 13 : Abstraction (Abstract Class and Interface)
Day 14 : Access Modifiers and Packages

Phase 3: Intermediate Java

Day 15 : Static Keyword (Variable, Method, Block)
Day 16 : Final Keyword
Day 17 : This and Super Keywords
Day 18 : Exception Handling (try-catch, custom exceptions)
Day 19 : Collections Framework - List
Day 20 : Collections Framework - Set and Map
Day 21 : Generics

Phase 4: Advanced Core Java

Day 22 : File Handling (I/O Streams)
Day 23 : Serialization and Deserialization
Day 24 : Multithreading Basics
Day 25 : Thread Lifecycle and Synchronization
Day 26 : Executor Framework (Thread Pools)
Day 27 : Lambda Expressions
Day 28 : Streams API

Phase 5: Advanced Concepts and Design

Day 29 : Java Memory Model and Garbage Collection
Day 30 : JVM, JDK, and JRE Deep Dive
Day 31 : SOLID Design Principles
Day 32 : Design Patterns (Singleton, Factory, Strategy)
Day 33 : Logging in Java (SLF4J basics)
Day 34 : Java 8 and Above Features Recap

Phase 6: Backend Development Essentials

Day 35 : Introduction to Spring Boot
Day 36 : REST API Development (Controller and Service Layers)
Day 37 : Dependency Injection
Day 38 : Spring Data JPA Basics
Day 39 : Exception Handling in REST APIs
Day 40 : Basic Project Structure and Clean Architecture

Repository Structure

java-study-guide/
│
├── README.md
│
├── Day1/
│   ├── concepts.md
│   ├── Example1.java
│   ├── Example2.java
│
├── Day2/
│   ├── concepts.md
│   ├── Example1.java
│
...

Learning Approach

- Focus on understanding concepts, not memorization
- Use real-world analogies for clarity
- Reinforce learning through hands-on coding
- Follow a structured progression from basics to advanced topics

Usage

Follow the study plan sequentially.

Each day builds on previous concepts, so completing topics in order
is recommended for maximum understanding.

Author

Name : Tejas Kumar S
Role : Senior Software Engineer

Contribution

This repository is designed to evolve.

Future improvements may include:
- Enhanced examples
- Additional edge cases
- Advanced real-world scenarios