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Core Java Tutorial Series

Learn Core Java Chapter by Chapter

This tutorial is designed as a detailed Core Java learning track with chapter pages, coding examples, interview-relevant concepts, and guided navigation from language basics to advanced runtime topics.

What this tutorial covers

The series covers Java fundamentals, JDK/JVM/JRE, data types, operators, control flow, OOP, interfaces, exceptions, strings, collections, streams, JDBC, multithreading, JVM memory, annotations, reflection, modern APIs, design principles, testing, performance tuning, enterprise APIs, and project or interview preparation.

Strong fundamentalsStarts with Java basics and JVM concepts
Interview relevantCovers OOP, collections, exceptions, and concurrency
PracticalIncludes JDBC, file I/O, testing, logging, profiling, and real code samples
Student focusedProgresses from language basics to enterprise architecture and professional habits

Chapter flow

  1. Chapter 1: Core Java Introduction, JDK, JVM, and JRE
  2. Chapter 2: Java Syntax, Variables, and Data Types
  3. Chapter 3: Java Operators, Control Flow, and Arrays
  4. Chapter 4: Core Java OOP, Classes, and Objects
  5. Chapter 5: Inheritance, Polymorphism, Abstraction, and Interfaces
  6. Chapter 6: Exception Handling and String API
  7. Chapter 7: Java Collections Framework
  8. Chapter 8: Generics, Lambda Expressions, and Streams
  9. Chapter 9: File I/O and JDBC
  10. Chapter 10: Multithreading and Concurrency
  11. Chapter 11: JVM Internals, Memory Management, and Garbage Collection
  12. Chapter 12: Core Java Projects, Interview Preparation, and Roadmap
  13. Chapter 13: Enums, Wrapper Classes, Annotations, and Reflection
  14. Chapter 14: Date Time API, NIO.2, Serialization, and Networking
  15. Chapter 15: Design Patterns, SOLID Principles, and Clean Code
  16. Chapter 16: Testing, Logging, Build Tools, and Modern Java Roadmap
  17. Chapter 17: JVM Performance, Garbage Collection Tuning, and Profiling
  18. Chapter 18: Enterprise Architecture, APIs, Security, and Integration

Start Chapter 1

Chapter 1

Core Java Introduction, JDK, JVM, and JRE

Understand what Java is, why it is popular, and how the JDK, JVM, and JRE work together.

 Chapter 2

Java Syntax, Variables, and Data Types

Learn Java syntax rules, variable declarations, primitive and non-primitive types, and type conversion.

 Chapter 3

Java Operators, Control Flow, and Arrays

Understand operators, conditions, loops, branching logic, and array handling in Java.

 Chapter 4

Core Java OOP, Classes, and Objects

Build a strong foundation in object-oriented programming with classes, objects, constructors, and encapsulation.

 Chapter 5

Inheritance, Polymorphism, Abstraction, and Interfaces

Learn the major OOP pillars that shape reusable and extensible Java designs.

 Chapter 6

Exception Handling and String API

Learn how Java handles runtime problems and how to work effectively with `String` and related text operations.

 Chapter 7

Java Collections Framework

Understand `List`, `Set`, `Map`, and the core collection classes used in real Java development.

 Chapter 8

Generics, Lambda Expressions, and Streams

Learn modern Core Java features used to write cleaner, safer, and more expressive code.

 Chapter 9

File I/O and JDBC

Learn how Core Java reads and writes files and how Java applications communicate with relational databases using JDBC.

 Chapter 10

Multithreading and Concurrency

Understand threads, concurrency concepts, synchronization, and the basics of writing safe multi-threaded Java code.

 Chapter 11

JVM Internals, Memory Management, and Garbage Collection

Learn how Java memory works, what heap and stack mean, and why garbage collection matters.

 Chapter 12

Core Java Projects, Interview Preparation, and Roadmap

Strengthen your Core Java foundation with project ideas, interview-focused revision, and a realistic roadmap before moving into deeper professional Java topics.

 Chapter 13

Enums, Wrapper Classes, Annotations, and Reflection

Learn advanced language features and metadata-driven programming concepts that appear in enterprise Java, frameworks, and interviews.

 Chapter 14

Date Time API, NIO.2, Serialization, and Networking

Cover important Java platform APIs for dates and times, modern file handling, object persistence concepts, and basic socket-based communication.

 Chapter 15

Design Patterns, SOLID Principles, and Clean Code

Advance from writing working Java code to designing maintainable systems with better abstractions, composition, and responsibility boundaries.

 Chapter 16

Testing, Logging, Build Tools, and Modern Java Roadmap

Complete the Core Java track with habits and tooling that prepare students for real project work, team development, and the next stage of enterprise Java learning.

 Chapter 17

JVM Performance, Garbage Collection Tuning, and Profiling

Go deeper into performance analysis by learning how Java applications are measured, profiled, and tuned in real runtime environments.

 Chapter 18

Enterprise Architecture, APIs, Security, and Integration

Finish the Core Java journey with a stronger view of how Java skills connect to enterprise APIs, layered architecture, integration patterns, and secure production systems.
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