A Java geek

Kotlin operators

Consider 2 types X and Y, and a function f defined as: class X, class Y and val f = { _:X → Y() }. In Kotlin, it’s possible to call the function f with a parameter of type X using invoke(): fun f(x: X) = Y() val y: Y = f.invoke(X()). The following calls the function f with a parameter of type X using invoke().

Development

What's the version of my Jekyll site?

A couple of years ago, I wrote how one could check the version of one’s deployed application. Recent technologies such as Spring Boot makes it even easier. It’s as important for regular applications as for static sites such as Jekyll. I wanted to have this blog display some basic Git data. As I publish from the tip of master and not from tags, the data I want is the commit hash.

Miscellaneous

Advices for junior conference speakers

Some years ago, I started my journey on the conference circuit. I did that on my own, in my free time. Without mentorship on how to do that, and with my gut feeling as the only guidance, I made plenty of mistakes… and I still regularly do. However, I now have a couple of hard-earned experience years behind me. Note that conferences are IMHO just a subset of public speaking in general. Meetups are another form, with a different set of constraints and challenges.

Java

Migrating the ServiceLoader to the Java 9 module system

A long long (long?) time ago, I wrote a post about the ServiceLoader. In short, the Service Loader allows to separate an API and its implementations in different JARs. The client code depends on the API only, while at runtime, the implementation(s) that is (are) on the classpath will be used. This is great way to decouple the client code from the implementing one.

Development

ONBUILD, the overlooked Docker directive

It’s hard to ignore Docker nowadays. There are a lot of blog posts available on the Web. The problem is that most always repeat the same. In this post, I’d like to focus on one directive that I find overlooked via a use-case: it is Java specific, but the parallel can be easily drawn to other tech stacks. The problem The situation is the following: as a developer, I’d like to use Docker as a way to package a JAR from the sources of my application.

JavaEE

Hibernate's Query-By-Example

Despite the current trend regarding &nbps;ORM frameworks, I never had any issue using JPA nor Hibernate. I must admit that my use-cases were pretty simple. Also, since that was already some years ago, we hosted those applications on our own on-site infrastructure so that the search for the ultimate performance - and its associated savings - was not a goal; empowering junior developers who were not familiar with a lot of technologies was.

Development

Conclusion of Exercises in Programming Style

This is the 20th post in the Exercises in Programming Style focus series. Over the course of several months, we worked through chapters of the Exercises in Programming Style book. Everything has to come to an end. But before switching to other interesting subjects, I’d like to dedicate this week’s post to some general thoughts about those articles.

Development

Exercises in MapReduce Style

This is the 19th post in the Exercises in Programming Style focus series. In the last episode of Exercises in Programming Style, we solved the word frequency problem with the Hazelcast library. This time, we are going to use MapReduce for that. MapReduce is a process consisting of two steps: Map performs transformations, filtering and sorting into different queues. Reduce aggregates the content of the queues into a result.

Development

Exercises in Programming Style with Hazelcast

This is the 18th post in the Exercises in Programming Style focus series. The previous week, we shared data among threads to solve the now well-known word frequencies problem. The very next day, I joined Hazelcast as a Developer Advocate. Therefore, I thought it would be extremely interesting to use Hazelcast In-Memory-Data-Grid to improve on the previous solution.

Nicolas Fränkel's blog