Recent posts

Dec 20, 2019

Customization of Asciidoctor PDF output

Using Asciidoc (the markup language) with the Asciidoctor toolchain is one of our favorite ways to write documentation. We mainly use it to create API documentation from our REST API backends using Spring REST Docs. Asciidoctor supports a variety of output formats, where HTML and PDF are ones we used the most. While the default PDF output already looks very good, it is always nice to be able customize the output a bit to better align with the project the documentation is created for. This post will explain exactly how to do that.


Oct 27, 2019

Using primary key objects with Spring Data and Hibernate

Most of the tutorials or blog posts that use Spring Data JPA use auto-generated primary keys. This post shows how you can use primary key objects instead of primitives like Long or UUID.


Oct 20, 2019

Spring Boot and Thymeleaf with CSS JavaScript processing using Gulp

This blog post will explain how to setup a Spring Boot project with server-side HTML rendering using Thymeleaf templates.


Jun 16, 2019

Ensure JUnit test fails when Cypress tests fail

In my previous blog post on Running Cypress tests with TestContainers for a Spring Boot with Thymeleaf application, I explained how to run Cypress tests as part of a JUnit test. However, the example did not actually fail the test if there are test failures in Cypress. Oops :-) In order to do that, we can use the support that Testcontainers has for watching the log output and parse that.


Jun 15, 2019

Running Cypress tests with TestContainers for a Spring Boot with Thymeleaf application

UPDATE: The full test class code in this post does not actually fail the test when the Cypress tests fail. See my updated example at ./blog/2019/06/16/ensure-junit-test-fails-when-cypress-tests-fail/[Ensure JUnit test fails when Cypress tests fail]. At the last ng-be conference I saw a demo of Cypress. Cypress allows to do functional testing of your web application, quite similar to Selenium for example, but still quite different. Ever since that time, I wanted to try it out, but never got around to it until this week.


Feb 21, 2019

Announcing BIOB an binary object storage library

I am announcing a new open-source project I am working on: BIOB It is still very early days, but there is already a fully functional local file system implementation and an in-memory implementation for testing. See for full details and a usage example on how to use the library in your own project. It does not depend on Spring or Spring Boot, but I have used it in that context so far because that is what I use for all of my projects.


Dec 24, 2018

Version 1.0.2 of Practical Guide to Building an API Back End with Spring Boot released

You can download an updated version of my book 'Practical Guide to Building an API Back End with Spring Boot' from InfoQ: The changelog can be viewed at


Sep 26, 2018

Switching between JDK 8 and 11 using SDKMAN

I have written about switching JDK versions on your mac before. With JDK 11 now being out, it is time to give an updated version.


Sep 10, 2018

Spring Boot book published via Infoq

I am so happy because today my Spring Boot book is finally available! See for all the details.


Aug 30, 2018

Tip on migration to Spring Boot 2 when using Flyway

Spring Boot 1.5.x uses Flyway 3 while Spring Boot 2.x uses Flyway 5. According to the official migration guide for Spring Boot 2, you need to do 2 releases to be able to migrate an application from Spring Boot 1 to Spring Boot 2 if you are using Flyway: First upgrade your 1.5.x Spring Boot application to Flyway 4 (4.2.0 at the time of writing), see the instructions for Maven and Gradle.