Keep the bar green to keep the code clean

This week, I’m very happy to break the news that Packt Publishing has come out with a JUnit book release, fresh from the press. The title Testing with JUnit, which I had the privilege of writing, is now available in the bookstores. It has been quite some work, but I...

Today, I am very pleased to inform you that Packt Publishing has put out a JUnit book announcement called Testing with JUnit on their website. A couple of months ago I was asked to write a book about one of my favorite topics – testing with JUnit. Needless to say...

I was recently asked how to initialize a new Git repository with JGit, i.e. achieve what git init /path/to/repo does. While creating a repository with JGit isn’t particularly difficult, there are a few details that might be worth noting. And because there are few online resources on the topic, and...

Implementing the observer pattern to provide Java event notification seems to be a straight forward thing to do. However, there are some pitfalls one easily can run into. Here comes an explanation of common mistakes I carelessly have produced myself on various occasions… Java Event Notification Let’s start with a...

Occasionally the average developer runs into a situation where he has to map values of arbitrary types within a particular container. However, the Java collection API provides container related parameterization only. Which limits the type safe usage of HashMap for example to a single value type. But what if you...

The following is a guest post by Leif Frenzel. I have the pleasure of knowing Leif for over a decade, back to a time when we worked together at Innoopract. Leif is an excellent software developer who gave many talks at conferences and did a lot of technical trainings. Focusing...

Some time ago we were in need for a hosted CI service for a project that was held in a private GitHub repository. And in Codeship we found a suitable solution to build, test and deploy the code from the private repository. Soon we got excited by the reliable internet...

OSGi Service Tests can be an efficient means to avoid problems related to dangling service references. As promised in my post about writing simple service contribution verifications, this time I introduce a JUnit rule that assists in testing interactions between components. OSGi Service Tests for Component Interaction Assume we have...

OSGi services come in handy for the development of systems based on loosely coupled components. But loose coupling can make it difficult to recognize problems related to dangling service references. Thus we usually run integrations tests to ensure the availability of service components at runtime. With the intention to reduce...