Anti Pattern: Don’t use Optionals for data repositories

Java 8 Optionals Java 8 introduced a new feature call Optionals. Optionals are an easy way to force the caller of a method to deal with a possible null return value:

If you use an Optional as the return type of your method, whoever calls the method will be reminded that it might return […]

Why using Spring’s @Value annotation is bad

@Value Configuration is an important topic of every application which has more than a couple of hundred lines of code. In case you are using Spring, you would typically use Spring’s @Value annotation to load values from a Java properties file. This could look like this:

If you do so, Spring would inject the […]

What static methods for interfaces tell you about the Java community

Recently I was putting together some code for an OSGi plugin at work. I created an interface to add listeners to an extension point. The code looked something like this:

The idea was simple: At some points in my application I would call all registered listeners, pass them an object and let them do […]