From Zero to Java 21 Microservices

From Zero to Java 21 Microservices

Build Intelligent Systems in 3 Days

Learn Java from scratch, master Spring Boot microservices, Kafka messaging, and AI/ML integration - fast, modern, and industry-ready

The demand for Java developers remains strong, but today’s roles require more than just knowing the syntax — modern systems are built as microservices, integrate with streaming platforms like Kafka, and increasingly depend on AI/ML services to personalize and automate experiences.

This 3-day immersive course takes complete beginners in Java and rapidly brings them up to speed with Java 21, the most modern and powerful release yet. We’ll cover the essentials of programming in Java, then transition into Spring Boot microservices with real-world communication patterns. Finally, we’ll explore how to integrate Kafka for event streaming and bring intelligence into systems with AI APIs, agentic AI, and ML-based recommendation services.

With over 30 years of industry experience, your instructor ensures this course is not academic fluff — it is built around what companies need right now.

Learning Outcomes

By the end of this course, participants will:

• Understand the fundamentals of Java programming (syntax, OOP, collections, exceptions, multithreading).
• Use modern Java 21 features (records, pattern matching, virtual threads) in practical coding tasks.
• Build and run a Spring Boot microservice with REST endpoints and database integration.
• Implement asynchronous communication between services using Kafka.
• Call external AI APIs from Java microservices to enrich business logic.
• Build a basic ML-based recommendation service and integrate it into the system.
• Understand how agentic AI can automate microservice operations and decision-making.
• Deliver a mini-project that ties all concepts together.

Prerequisites

• No prior knowledge of Java is required.
• General familiarity with computers and basic coding logic (e.g., what variables and loops are) will help.
• Laptop with Java 21 JDK, IDE (IntelliJ / Eclipse / VS Code), Maven/Gradle, and Docker pre-installed (setup guide provided before the course).
• Curiosity and willingness to learn at an accelerated pace.

Detailed Training Outline

1. Foundations of Java 21 Programming

• Getting Started
  • Installing Java 21 and IDE setup
  • Running the first Java program (Hello World)
  • Understanding compilation and execution
• Core Syntax & Basics
  • Variables, data types, operators
  • Control structures (if, switch, loops)
  • Functions & methods
  • Input/output in Java
• Object-Oriented Programming (OOP)
  • Classes and objects
  • Constructors, methods, and fields
  • Inheritance and polymorphism
  • Encapsulation and abstraction
  • Interfaces vs abstract classes
• Core Java Libraries
  • Collections framework (List, Set, Map)
  • Sequenced Collections (Java 21)
  • Exception handling (try, catch, finally)
  • File handling and streams
• Modern Java 21 Features
  • Record classes for data objects
  • Pattern matching for switch
  • Virtual threads for concurrency (Project Loom)
  • String templates and unnamed variables (preview features)
• Hands-on Exercises
  • Build a simple console-based banking system
  • Use collections to store and retrieve user data
  • Run concurrent tasks with virtual threads

2. Introduction to Spring Boot & Microservices

• Spring Boot Essentials
  • What is Spring Boot and why microservices?
  • Project structure, starters, and auto-configuration
  • Creating RESTful APIs with Spring MVC
  • Connecting to databases with Spring Data JPA
  • Basic error handling and validation
• Microservices Concepts
  • Monolith vs microservices
  • Service boundaries and responsibilities
  • Communication patterns: synchronous vs asynchronous
  • Deploying microservices with Docker
• Hands-on Exercises
  • Build a User Service microservice (CRUD API)
  • Build an Order Service microservice connected to a database
  • Containerize both services with Docker

3. Kafka and Event-Driven Microservices

• Kafka Basics
  • Topics, partitions, producers, consumers
  • Kafka vs REST communication
  • Event-driven system design
• Spring Boot + Kafka Integration
  • Configuring Kafka in Spring Boot
  • Producing and consuming messages
  • Handling errors and retries
  • Event logging and monitoring
• Hands-on Exercises
  • Publish order events from Order Service
  • Consume order events in Inventory Service
  • Implement an asynchronous notification service

4. AI, ML & Agentic AI Integration

• Calling AI APIs
  • Overview of AI APIs (LLMs, NLP, computer vision)
  • Making REST calls to AI APIs from Spring Boot
  • Handling responses, caching, and errors
• ML-Powered Recommendation Service
  • Basics of recommendation systems (content-based, collaborative filtering)
  • Simple implementation (pre-trained ML model or lightweight algorithm)
  • Exposing recommendations via REST API
  • Integrating recommendations into user flow
• Agentic AI for Microservices
  • What are agentic AI systems?
  • Use cases in monitoring, automation, and decision-making
  • Building a simple AI agent microservice to monitor logs and trigger alerts
• Hands-on Exercises
  • Build a Recommendation Service microservice
  • Integrate with User Service to suggest products
  • Add AI agent to monitor Kafka event failures and auto-restart services

5. Capstone Project