Java 25 Ready: Java 8-25 + Spring Boot 3 – In Simple Terms | Udemy

This course has been selected by Udemy for inclusion in Udemy Business — Udemy’s curated collection of high-quality courses used by organisations worldwide.

“Udemy Business is a curated (carefully chosen) selection of high-quality Udemy courses — like yours.” — Udemy

“Only 3% of all courses are chosen for Udemy Business.” — Udemy

The course is fully updated to Java 25 and covers Java 8, 11, 17, 21, and 25 — showing how modern Java evolved across these releases.

Since being selected for Udemy Business, the course has been significantly expanded and updated, including:

• Spring Boot 3

• Java 21 and Java 25 content

• 2 Full OCP Certification Practice Tests

• 5 Additional OCP Practice Quizzes

• All code now available on my GitHub repositories

Who this course is for (important)

This is an advanced Java course.

It is designed for:

• Developers who already know Java fundamentals
• Learners who want to properly understand modern Java (8 → 25)
• Those preparing for Oracle OCP certifications
• Professionals who want deep understanding

Note: Java fundamentals are not covered (classes, interfaces, operators, basic syntax).

The course starts immediately with Java 8 lambdas and streams.

What makes this course different

Many Java courses:

• Stop at Java 8 or Java 11
• Treat newer versions as bolt-ons
• Focus on syntax rather than reasoning

You will:

• Learn how Java evolved from Java 8 through Java 11, 17, 21, and 25
• Understand why language features exist, not just how to use them
• Work through assignments that evolve across Java versions
• Learn with both real-world development and certification in mind

Topics are explained using:

• Clear theory
• Extensive, annotated code examples
• Assignments that reinforce understanding
• Video explanations for all practice questions

What students say

(A small selection — more reviews are available below)

“Great course, great explanation. The best course in Java I have seen so far.” — Kaylan AD

“I am nearing retirement. I have learned more about lambdas here than in the rest of my career.” — Robert R

“This course is a jewel… I passed the OCA and hope to pass the OCP now.” — Yigit K.

“Definitely the best Java course I’ve ever taken… especially the Java 21 features.” — Anna

“Excellent detail, perfect pace, and outstanding explanations.” — Ricardo Q.

“So far its the best course for java professional who want to start from new features of java 8” — Ankit M.

Course overview

Java currently has five Long-Term Support (LTS) releases:

Java 8, 11, 17, 21, and 25 — and this course covers all of them.

This course is the successor to my other Udemy Business course:

“Java 8 OCA (1Z0-808) Certification – Master the Fundamentals”.

As a result:

• Java fundamentals are assumed
• The course begins with advanced Java 8 topics
• Each later Java version builds on the previous one

Java 8 – Advanced Topics

• Lambda Expressions
• Streams
• Generics
• Collections
• Concurrency
• JDBC
• File I/O and NIO.2
• Serialisation
• Localisation

Assignments are included for lambdas, streams, and collections.

Java 11

• Modules (examined in detail with examples)
• Local Variable Type Inference (LVTI)
• Private interface methods
• Annotations
• Security

Java 17

• Sealed classes
• Records
• Switch expressions and pattern matching
• Text blocks

A significant assignment covering all Java 17 topics is included.

Java 21

• Unnamed classes and instance main methods (preview features)
• Record patterns
• Pattern matching for switch
• Sequenced collections
• Virtual Threads

An assignment building on the Java 17 assignment is included.

Java 25

• Markdown documentation
• Unnamed variables and unnamed patterns
• Module import declarations
• Compact source files and instance main methods (finalised)
• Flexible constructor bodies
• Scoped values
• Stream gatherers

An assignment building on the Java 21 assignment — and incorporating all Java 25 features — is included.

Spring Boot 3 Application (updated to Java 25)

• Configuring a Spring Boot application and dependencies
• Understanding how RESTful applications work
• Dependency Injection / Inversion of Control
• Architecture overview
• Code explained in detail
• Testing with Postman

An assignment is used to reinforce the material, and its solution is explained in detail.

OCP Certification Preparation

2 Full OCP Practice Tests

• 50 questions each
• 120-minute time limit
• 68% pass mark (as per Oracle exams)
• Every question has a detailed video explanation

Even if you do not plan to take the certification, the solution videos provide excellent learning opportunities.

5 OCP Practice Quizzes

• 69 MCQ questions in total
• Every question explained with a video solution

This course supports preparation for:

• Java 8 OCP (1Z0-809)
• Java 11 OCP (1Z0-819)
• Java 17 OCP (1Z0-829)

It also works very well alongside the Enthuware OCP Certification tool.

About the instructor

I am a PhD-qualified University lecturer and have been teaching since 2002.

For over 13 years, I have taught advanced Java on a bespoke Masters programme on behalf of a highly regarded software company.

I have co-authored two books:

• Learn Java with Projects
• Java Memory Management

I love teaching, and this course brings together:

• My academic background
• My industry experience
• My passion for clear, structured explanations
• A strong attention to detail, particularly suited to Oracle Java certifications

Final note

This course is designed to give you:

• A deep understanding of modern Java
• Confidence in real-world development
• Strong preparation for Oracle OCP exams

If you already know Java fundamentals and want to truly master Java 8 through Java 25, this course is for you.

More student feedback

“Extraordinary Explanation.” — Darshan P.

“The course is amazing, learned a lot of good things.” — Rakesh L.

“This course provides an exceptional hands-on learning experience… invaluable resource for Java developers.” — Naveen KG

“Sean is technically superior in Java; he’s the best I know.” — Axel B.

“This course is a jewel… Sean answers questions… I passed the OCA… hope to pass the OCP now.” — Yigit K.

“Easy to follow and straight to the point.” — Daniel M.

“Great how detailed it is.” — Ali A.

“Excellent – especially like the detail and pace.” — Alan C.

“One of the best courses so far… perfect talking speed… content is excellent.” — Ricardo Q.

“Very useful exercises and really interesting syllabus.” — Laura

“Clearly explained, easy to follow and understand. Good code examples.” — Ugyen N.