Java Chapter Index

Introduction

This index lists all 50 chapters in the Hello Code Java track (49 lessons plus this index), grouped by topic. Use it to jump to a lesson or plan your path toward Spring Boot, JDBC, and backend work.

Prerequisites

  • None—this page is a map, not a lesson

Getting Started (01–07)

#Chapter
01What Is Java
02Install Java on Windows
03Install Java on macOS
04Install Java on Linux
05Write and Run Hello World Without an Editor
06Install a Code Editor for Java
07Write and Run Hello World in IntelliJ IDEA

Core Syntax (08–20)

#Chapter
08Java Coding Standards for Beginners
09Variables in Java
10Comments: Write Code Humans Can Read
11Java Operators
12Numbers in Java
13Mini Exercise: Sum Two Numbers
14Strings in Java
15Java Keywords
16Conditional Statements
17Loop Statements
18Arrays
19Ranking Game
20Guess the Number Game

Object-Oriented Programming (21–33)

#Chapter
21Object-Oriented Programming in Java
22Methods
23Classes
24Generics
25Enums
26Inheritance
27Abstract Classes
28The Object Class
29Packages and Directory Structure
30Interfaces
31Polymorphism
32Annotations
33Functional Programming: Lambda and Streams

Collections (34–39)

#Chapter
34Java Collections Overview
35ArrayList
36HashMap
37Score Entry and Query
38HashSet
39Deduplicate and Sort Math Scores

Concurrency, I/O, and Modern Java (40–46)

#Chapter
40Exception Handling
41Multithreading Basics
42Java 21 Modern Features
43Regular Expressions
44File Handling
45Date and Time
46JSON Handling

Build Tools and Wrap-Up (47–50)

#Chapter
47Maven
48Gradle
49Book Recommendations
50Java Chapter Index (this page)

Suggested Learning Paths

Beginner console path: 01–20 → 34–39 → 40 → 49

OOP depth: 01–18 → 21–33 → 34–39

Backend engineer path: complete track → Spring Boot 3JDBCMySQL; optional documents via Spring Data MongoDB

Java API + Vue SPA: Spring Boot REST → Vue 17Vue 24–25; deploy with Nginx + Vue 20

Compare with Python: Python track covers similar fundamentals with different syntax and tooling.

FAQ

JDK version?

This track assumes JDK 21 (LTS) — see chapters 02–04.

Maven or Gradle?

Learn both at a high level (47–48); teams pick one per project. Spring Boot supports either.

Missing chapter index before?

Chapters 01–49 were the lessons; this page is the map added as chapter 50.

Report an error?

Git fork workflow.