Deploy Spring Boot Applications With More Confidence and Fewer Regressions

Learn How to Master Automated Testing and Become More Productive & Confident with the Testing Spring Boot Application Masterclass

Before taking this Masterclass

Before Taking the Testing Spring Boot Applications Masterclass
  • You're Most Likely Have a Cargo-Cult Testing Approach
  • You're Testing Your Application Because You Have to Reach a Specific Coverage Treshold Goal
  • You're Frustrated with the Little Content & Articles About Testing Spring Boot Application Effectively
  • You've Lacking Guidance and Recipes for Testing Your Real-World Applications
  • Firefighting Mode and Jumping from one Bugfix to Another
  • You're Working with a Brittle and Untested Codebase

After taking this Masterclass

  • You Have an In-Depth Knowledge About Testing Spring Boot applications
  • You have Recipes and Best Practices for Unit, Integration, and End-to-End Testing
  • Testing Is No Longer an Afterthought for You
  • You Start Helping Your Team And Educate them About Testing Techniques
  • You Understand How Testing Spring Boot Applications Work
  • There Are No Excuses Anymore As You'll joyfully Write Tests As you Now Know the HOW

TL;DR: This online course is a deep-dive on effectively writing unit, integration, and end-to-end tests for Spring Boot applications to become more confident and productive.

Limited Offer: 30% Discount & Free TDD with Spring Boot Done Right Course Enrollment


Knowing How to Effectively Test Separates the Serious Engineer from a Hobby Developer

“Quality is not an act. It is a habit.” – Aristotle

Do you remember writing your first Spring Boot application? You were excited that you now finally expose data via an API and can connect to a database.

Testing your application was the last thing you could think of at this moment.

Once you start using Spring Boot in a professional environment there is no way around testing. Testing your application gives you confidence, fearless deployments on Friday afternoons and a good night of sleep.

Most tutorials and courses about testing barely go beyond the Hello World example of testing a calculator.

This does not prepare you for the real world where your application faces database access, external systems, messaging system, network, etc.

There are so many great libraries and techniques out there for the Java ecosystem when it comes to testing. Mastering them all, right after you understand the basics about Spring Boot, is hard.

Testing is joyful once you are familiar with all the great tools you have access to: JUnit, Mockito, AssertJ, Hamcrest, JsonPath, JSONAssert, Testcontainers, Selenium, LocalStack, Awaitility, and not to forget the whole Spring Testing support.

Especially with Spring Boot you get so much functionality when it comes to testing. What you need are recipes to tackle testing different parts of your applications and then apply them.

This Testing Spring Boot applications Masterclass is all about making you an expert when it comes to testing Spring Boot applications in an efficient way.

All You Need to Know About Testing
Spring Boot Applications

The number of testing libraries is huge in the Java ecosystem. One might get overwhelmed with all the different solutions. 

This online Masterclass guides you through every testing library you need to verify your Spring Boot application is working as expected.

After working with this course, you not only have recipes at hand to test different parts of your application, but you are also familiar with industry best practice.

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Watch Four Preview Lessons of the Masterclass

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Enroll now and never worry about testing your Spring Boot application again! All content is up-to-date with Spring Boot 3 and Java 21.

Limited Offer: 30% Discount & Free TDD Course Enrollment

Your Journey to More Confident Releases

Testing Spring Boot Applications Course Map

Stop The Firefighting Mode

Whether you just started with Spring Boot or are already using it in several projects, this Spring Boot Testing Masterclass guides you through all relevant parts of testing Spring Boot applications.

Understand What and How to Test

You are unsure which parts of your application to test? There is a good chance that you are not focusing on the relevant parts of your application you should test.

Go Beyond Trivial Unit Testing

After working with this course you'll have recipes at hand to test all non-trivial parts of your application like database access, HTTP communication, using cloud services (e.g. SQS from AWS), etc.

Master Different Testing Libraries

Not only will you be able to use all presented testing libraries for your application, but also understand what they are about and when to use which. Knowing when to use which library is a key skill.

Testing Best Practices

This Masterclass includes an own section about industry best practices for testing applications. Make use of knowledge from years of writing tests for enterprise applications.

Here’s What Course Students Say About This Masterclass

Wim Deblauwe Course Student

Wim Deblauwe

Software Engineer - Homepage

Philip has made a fantastic overview of the full testing landscape of Spring. The videos are clear and explain details and common pitfalls in great depth. Looking forward to the rest of the course.

PS: Wim is also book author of Taming Thymeleaf and Practical Guide to Building an API Back End with Spring Boot.

Anton Ždanov Full Stack Developer

Anton Ždanov

Full Stack Developer - LinkedIn

For me testing a Spring application seemed like a challenge involving digging through numerous blog posts, documentation for JUnit, Mockito, and Spring Testing Reference which provide valuable information but are spread out and don't necessarily show the best practices.

After watching the Testing Spring Boot Applications Masterclass course I feel more confident in writing different types of tests for my apps. The course, videos, and the GitHub repository were of invaluable use to me demonstrating various testing mechanics the Spring ecosystem provides, and I will keep referencing the course materials in the future.

The application that is tested in the course is quite complex and covers a lot of real-world testing challenges one might encounter, which I found immensely useful for seeing the bigger picture.

Siva Course Student


Software Engineer and Blogger working for AtomicJar (company behind Testcontainers)

Detailed review of the Masterclass on his blog

I got an opportunity to review the course I find it wonderful for learning how to test Spring Boot applications leveraging modern testing frameworks and libraries....

I would highly recommend Masterclass for anybody working with Spring Boot applications.

Read the full review here.

What You'll Learn

Overview of the different Masterclass Modules


Module 1: Introduction 

We'll start with an application walk-through, to get you familiar with the code base we test throughout the Masterclass.

At the end of this module you'll be able to start the Book Reviewr application and its infrastructure components on your machine.


Module 2: Testing With the Spring Boot Starter Test

Getting familiar with the swiss-army knife that every Spring Boot project includes: Spring Boot Starter Test.

We'll cover all testing libraries that come with this starter and take a detailed look into testing with JUnit 5 and mocking with Mockito.


Module 3: Testing Database Access

Start writing efficient tests for your database layer while utilizing Spring Boot test features like @DataJpaTest, TestEntityManager, @Sql, etc.

Furthermore, with this module you'll start using Testcontainers to replace the default in-memory database, learn how you can pre-populate your database, and understand the pitfalls when writing tests where the EntityManger is involved.


Module 4: Testing the Web Layer

MockMvc to the rescue!

Learn how to effectively test your web-layer (@RestController and @Controller) in isolation. You have your endpoints secured with Spring Security? No problem! There is great support available to ensure only authenticated users with the correct privileges reach your endpoints.


Module 5: Testing Further Slices of our Application

Ever wanted to know how to test your WebClient or RestTemplate HTTP calls? How to ensure your business logic is working as expected and how to verify your messaging controllers?

In this module, we'll tackle further slices to effectively test different parts of our application in isolation. In addition, we'll write our own test slice.


Module 6: Writing Tests With the Whole Spring Context

It's time to write integration tests using @SpringBootTest!

With the knowledge of previous modules, we can mock almost any external infrastructure component, except Keycloak. We'll introduce WireMock to mock the HTTP interaction with the identity provider or any other system during application startup (e.g. Salesforce, Stripe, SAP, etc.).


Module 7: Writing Web Tests

Writing end-to-end tests to ensure users can interact with your application.

Having automated web-tests for your happy-paths can literally save your ass. We'll make the most of Selenium and Selenide by verifying the Book Reviwr application without any manual WebDriver setup (including VNC recording, screenshots on failure, etc.).


Module 8: Testing Best Practices

Build tool configuration, test strategies, naming strategies, testing static methods, working with time, test report visualization within your CI (e.g. Jenkins, GitLab CI, Azure DevOps) server, etc.

... and last but not least: Drastically reduce your build times with Spring's Context Caching mechanism.

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Your The Course Instructor:

Philip (rieckpil)

I'm an independent IT consultant living in Berlin. I started working with Java back in 2015 and I used Spring Boot ever since. Automated testing was always one of my biggest pain points as I didn't know how to tackle is.

As of today, testing is an integral part of my daily work.

I'm teaching Java topics on YouTube since 2018 and I'm writing content about the Java ecosystem on my blog since 2017.

More than 10.000 course students have enrolled in my online courses. Besides that, I'm also actively helping developers on Stack Overflow (10k+ reputation) with their questions around testing Java applications.

Once I understood the ins and outs of the Java testing landscape, writing tests makes as much fun as writing production code for me. I'm a won around TDD (Test Driven Development) practitioner and regularly share testing techniques among my colleagues and clients.

Here’s What People Are Saying About the Course Instructor

Tom Hombergs

Tom Hombergs

Founder of

Philip is a dedicated developer and doesn't give up until he has understood the details of a topic.

In his courses and articles, he transfers this knowledge to you and they leave you smarter than before. 

Looking forward to working with you in the future, Philip

Vlad Mihalcea

Vlad Mihalcea

Founder of

Philip is a very skilled content creator who managed to publish high quality articles and videos that cover a wide range of topics, like Spring, Java EE, or Jakarta EE.

He pays a lot of attention to details, so if you enjoyed his articles and videos, you are surely going to love his video courses.

Marco Behler

Marco Behler

Founder of

How can you not love what Philip is doing?

Tons of actionable tutorials and content across the Jakarta EE and Spring universes.

Highly recommended!

Philip's Recent Spring Boot Testing Conference Talks

Learn More About the Course Instructor and Spring Boot Testing Expert Philip

Things I Wish I Knew When I Started Testing Spring Boot Applications

Testing is an integral part of software development, and unfortunately, some teams treat this topic neglectfully.

This talk will give you an overview of best practices, pitfalls, and recipes for testing Spring Boot applications.

Philip shares the things that he wish he had known when he started testing Spring Boot applications.

Watch the talk on YouTube.

How Fixing a Broken Window Cut Down Our Build Time
By 50%

Our journey of getting rid of @DirtiesContext on top of an abstract test class (aka. the "broken window") that made reusing the Spring TestContext impossible and resulted in ever-growing build times.

After fixing this "broken window", our overall build time went down by 50% from 25 to 12 minutes.

Watch the talk on YouTube.

Why You MUST Invest Time in Learning How to Test Spring Boot Applications

When was your last outage or downtime caused by a bug that could have been prevented with a test? How much did your company lost in direct revenue or indirectly by losing customer satisfaction? How less productive are you and your coworkers because of missing automated tests?

Putting in numbers is hard, but I guess every minute a non-trivial application is not working as expected results in costs or lost revenue of $100.000+.

On the other side, consider how uncertainty paralyses you when you want to refactor an existing code base that lacks tests. Or you are new to a project and want to introduce a new feature. Testing things afterwards manually is a cumbersome and repetitive tasks. 

We, as engineers, are lucky to have tools around us that can automate such cumbersome and repetitive tasks. So let's start using them by learning how to effectively test our applications.

Once you know your testing toolkit, writing tests becomes joyful.

Your Path Towards More Confidence & Productivity

Introduction to the Masterclass



Getting Started

Keeping the Course Content Up-to-Date


Spring Boot 3 Migration

Application Setup


Setup for Java Development

Infrastructure Setup With Docker Compose

Application Walkthrough


Application Architecture

Maven Dependencies

Flyway Migration Scripts

Application Configuration

AWS SDK Overrides

Introduction to the Backend Code

Keycloak Configuration Walkthrough

Application Walkthrough

Testing With the Spring Boot Starter Test

Introduction to the Spring Boot Starter Test Dependency


Anatomy of the dependency

Managing library versions

Introduction to JUnit 5


Writing Your First Test With JUnit 5

Verify the Test Outcome With Assertions

Lifecycle of a Test

More on Assertions

Specifying the Name of a Test

Write Parameterized Tests

Your First JUnit 5 Extension

Happy-Path Testing

Parallelization of Tests

Introduction to Mockito


Introduction to the Class Under Test

Mocking Method Calls With Mockito

Your First Test With Mockito

Mocking the Behaviour of the Repository

Instrumenting a Mock to Throw an Exception

Full Happy-Path Test With Mockito

Capture Method Arguments and Verify Invocations

Additional Test Libraries of the Starter


Introduction to Hamcrest

Introduction to AssertJ

Introduction to JSONAssert

Introduction to JsonPath

Spring Boot Starter Test Summary


Spring Boot Starter Test Conference Talk

Testing Database Access

The Secret Weapon to Test Your Database Layer: @DataJpaTest


Introduction to the JPA Domain Model

What to Test When Using Spring Data JPA

Start Using @DataJpaTest

Resolving context startup errors

Why and When to Use the TestEntityManager

Pitfalls of the First Level Cache

Transactional Support

Using P6SPY for More Insights

Replacing the In-Memory Database


The Rationale Behind Not Using In-Memory Databases

Using Testcontainers for the First Time

Managing the Lifecycle of a Container

Improve Build Times by Reusing Containers

Solutions to Pre-Populate Your Database

Testing the Native Query

Recap of the Database Access Module

Testing the Web Layer

The Secret Weapon to Test Your Web Layer


Why Unit Tests Are Not Enough

Introduction to @WebMvcTest

Getting the Setup Right

Defining On Which Level to Mock

Your First Test With @WebMvcTest

More Tests for the BookController

Advanced Usage


Introduction to the ReviewController

Verifying the First Behavior

Testing the First Secured Endpoint

Additional Ways to Provide Authentication

Happy-Path Testing For Creating Reviews

Ensure We Validate Incoming Reviews

Access to Role-Based Secured Endpoints

Recap and Learnings of This Module

Testing Further Slices of Our Application

Testing HTTP Clients Using the RestTemplate


Introduction to Testing HTTP Clients

The Power of @RestClientTest

First Test Using the MockRestServiceServer

More Assertions for the Happy-Path

Handling Partial Responses

Test a Failure of the Remote System

More Expectations on the HTTP Request

Testing HTTP Clients Using the WebClient


Required Setup for the MockWebServer

Testing the Happy-Path Using MockWebServer

Verify Behavior on Partial Responses

Testing Failure of the Remote System

Implement and Test Retry Mechanism for More Resiliency

Testing Business Logic in Isolation


Which Logic to Verify

Getting the Setup Right for Testing the ReviewService

Verify the First Error Scenario

Ensure We Don't Store Reviews With Bad Quality

Happy-Path Testing For Storing a Review

Testing a Custom Application Slice


Choosing the Application Part for Isolated Testing

Introduction to LocalStack

Creating a Spring Application Context With Only One Message Listener

Understanding the Spring Cloud AWS Auto Configuration

Overriding the AWS SQS Client

Creating a Local SQS Queue and Applying the Configuration

Happy-Path Testing For the Whole Listener Process

New Spring Cloud AWS Sliced Test Context Annotation

Recap on How to Create a Sliced Spring Context for Testing

Writing Tests With the Whole Spring Context

Remaining Setup to Start the Whole Spring Boot Application


What's Currently Missing to Start the Whole Context

Creating an Integration Test Profile

First Try to Start the Whole Context

Introducing WireMock to Mock HTTP Communication

Creating an ApplicationContextInitializer for WireMock

Mocking the OpenID Configuration Response

Mocking the JWKS (JSON Web Key Set) Response

Making Use Of the WebTestClient to Access the Backend

Creating a Valid JWT to Access Our Endpoints

Writing Integration Tests for Our Application


Verifying the Book Synchronization Process

Refactor Our WebClient to Mock the HTTP Response

Extract Integration Test Setup to a Central Place

Ensure Users Can Create Reviews

Develop the Missing API Endpoint Test-Driven (TDD)

Test the Statistics Endpoint With Reviews From Multiple Users

Recap of This Module About Integration Tests

Writing Web Tests

Providing the Whole Application Infrastructure


What's Missing Compared to Writing Integration Tests

Creating a Web Test Application Profile

Using Testcontainers to Start the Docker Compose Environment

Using Selenide to Write Concise Web Tests

Writing the First Test With Selenide

Making Screenshots During Test Execution

Further Hints on the Web Test Setup

Using Testcontainers With Selenide

Recording the Web Test With a Video

Test the Happy-Path User Journey


Inserting Reviews During the Web Test

Verifying the Outcome of the Test

Refactoring the Test to Page Objects

Recap on Writing Web Tests

Testing Best Practices

Naming and Test Strategies


Defining Your Own Test Strategy

Naming Conventions for Your Tests

Build Tool Configuration


Maven Surefire and Failsafe Plugin Configuration

Visualizing Test Results Within a CI Server

Reduce Build Times With Spring's Context Caching


Introduction to Context Caching

Context Caching in Action

Making the Most Of Spring's Context Caching

Further Best Practices for Context Caching

General Testing Advices


Working With Time

Mocking Static Method Calls

Using GitHub Actions for Your Project

Next Steps

Thank You for Completing the Masterclass

Detailed Module Overview

Discover what we're discussing in the eight modules of the Testing Spring Boot Applications Masterclass.

  • Course application walk-through (Book Reviewr)
  • Understand the AWS setup for this application
  • Get to know the OAuth2 setup of the application using Keycloak
  • Effectively test your web-layer in isolation using @WebMvcTest
  • Test protected controller endpoints with ease
  • Write tests against a mocked Servlet environment using MockMvc
  • Get rid of manual WebDriver setup efforts (Testcontainers & Selenide)
  • Record the web test and make screenshots on-demand
  • Start a Docker Compose environment for your end-to-end test
  • Discover all testing libraries that the Spring Boot Starter Test includes
  • Getting started with JUnit 5 (parallelization, custom extensions, etc.)  
  • Writing assertions for JSON payloads using JSONAssert & JsonPath
  • Write tests for HTTP clients (e.g. WebClient or RestTemplate)
  • Testing business logic in isolation
  • Write custom test slices e.g. for the SQS subscriber and include only relevant beans to the Spring Test Context 
  • General tips & tricks around testing
  • Making the most of Spring's Context caching to speed up your tests
  • Practical advice for your test structure & naming conventions
  • Writing isolated tests for your database layer using @DataJpaTest
  • Pitfalls when writing tests with the EntityManger
  • Use Testcontainers to write tests against your database
  • Mock components that are required during application startup (e.g. identity provider, Salesforce, external APIs, etc.)
  • How to structure and what to write  integration tests for 
  • Mock Keycloak or any other OAuth2 identity provider

What this Masterclass Is All About

This Masterclass is ...

  • An in-depth course on testing Spring Boot applications
  • Your go-to resource for hands-on unit, integration, and end-to-end testing recipes and best practices
  • A comprehensive guide on how to use testing tools and libraries for testing modern microservices
  • A place to understand how testing Spring Boot applications work
  • Your excuse-killer for writing no tests as you'll joyfully write them once you know the HOW

The Masterclass is not ...

  • A course on developing microservices
  • A course on mastering TDD (TDD is covered here)
  • A course on testing or developing frontend applications
  • A beginner-friendly course for Java and Spring Boot newcomers. You should have some basic experience with those technologies
  • A course to be rushed through while multi-tasking in parallel 

The Masterclass in Numbers