Sealed Classes in Kotlin – An Explanation

Sealed Classes in Kotlin – An Explanation

Sealed Classes in Kotlin – An Explanation Today I came across Sealed Classes in Kotlin, which I had never heard of before. After some research I found that this concept is nothing new and is also available in Scala for example. So, yet another Scala feature JetBrains considered relevant and suitable for Kotlin? I like that 🙂 …

Read More Read More

Generic Types and Variance in Kotlin compared to Java

Generic Types and Variance in Kotlin compared to Java

Basics – What is Variance? Many programming languages support the concept of subtyping, which allows us to implement hierarchies like “A Cat IS-An Animal“. In Java we can either use the extends keyword in order to change/expand behaviour of an existing class (inheritance) or use implements to provide implementations for an interface. According to Liskov’s substitution principle, …

Read More Read More

Setup Vert.x Application written in Kotlin (Gradle Build)

Setup Vert.x Application written in Kotlin (Gradle Build)

I decided to write a Vert.x application in combination with Kotlin in a simple example because I’m really interested in Reactive Programming and love to use Kotlin. This post will give some basic information on Vert.x as a tool set for writing reactive applications on the JVM as well as a few words on Kotlin. In the end, I want to demonstrate …

Read More Read More

Java Oracle Certification

Java Oracle Certification

Java Oracle Certification – Should you consider it? I took the OCA SE 7 Programmer I Certification exam two years ago in 2015, which I passed successfully with a score of 86%. This year I will be taking the second exam of this certification path called OCP SE 7 Programmer II. In this post I want to reflect why taking …

Read More Read More