Thomas Sundberg

November 20, 2015

Expected exceptions

Filed under: Java, Programming, TDD — Tags: , , , , — Thomas Sundberg @ 11:27

Sometimes you want to verify that an exception is thrown in your code.

Let me show you three different ways to verify that the expected exception has been thrown.


November 6, 2015

Different asserts are good in different situations

Filed under: Java, Teaching — Tags: , , , — Thomas Sundberg @ 11:49

When should you use which assert? It is a question developers new to unit tests may ask themselves.

It is easy as a seasoned developer to think that this is obvious. It isn’t when you are learning.


October 27, 2015

When is evolutionary design a good way to implement software?

Designing software can be done in different ways. The time and effort spent on designing have an important effect on the result. An interesting question is: When should you allow the software to evolve using Test Driven Development, TDD, and when should you not?

Software Development Gang

This blog post is the result of a session at an open space with the Software Development Gang in Ghent, Belgium, June 2015.


September 13, 2015

Conference do’s and don’ts

Filed under: Public speaking — Tags: , , , — Thomas Sundberg @ 12:41

I have done some conference presentations the last few years. It is interesting to compare conferences in retrospective. It is possible to notice some common mistakes as well as some really good things. It is, unfortunately, often easier to criticize instead of attributing good things.

Most conferences I attend have very engaged organizers. They don’t just do a job; they are passionate about it at the same time. It is great to be able to contribute in such environments!

Then there are some who just does a job and it is obvious that there is a difference.


September 10, 2015

Increase the available disk on a CentOS host maintained by Vagrant and VirtualBox

Filed under: Linux — Tags: , , , , — Thomas Sundberg @ 22:36

Virtual servers are fantastic when you need to test something and want to make sure that you have a well know environment. A virtual server has no value. You can create it over and over again and it will only cost you some time to start and stop.

VirtualBox and Vagrant is a really easy combination to get started with. However, it may turn ut that the base box you use need to be enhanced. I will show you how you can increase the disk space available on the virtual host. Unfortunately, it isn’t as easy as one could hope for. But it is possible and I will show you how. When the disk has been increased, I will repackage the virtual host so it can be reused easily.


YUM Cheat sheet

Filed under: Automation, Linux — Tags: , , , , — Thomas Sundberg @ 21:50

Remembering the syntax for yum is something I seem to have problems with. To simplify my own life, and possible yours, here is a list of some commands I find useful. Some of them should be executed as root.


RPM Cheat sheet

Filed under: Automation, Linux — Tags: , , , , — Thomas Sundberg @ 21:42

It turns out that I always have to search for the syntax when working with RPMs. To simplify my own life, and possible yours, here is a list of some commands I find useful. Some of them should be executed as root.


August 21, 2015

Packaging a zip file from Java using Apache Commons compress

Filed under: Gradle, Java, Programming — Tags: , , — Thomas Sundberg @ 16:10

How do you create a zip file with Java? One option is to use Apache Commons Compress.

This example shows you how.


July 17, 2015

Tell, don’t ask

Filed under: Programming — Tags: , , , , — Thomas Sundberg @ 17:02

Objects that expose wrong information are complicated to work with. They force you to dig for the information you really need. It is easy to create a model where the users are expected to know a lot about the domain and therefore force them to dig deep into an object structure to get the information they currently need. This can be avoided if you strive for telling objects what to do and only ask them occasionally.


June 19, 2015

Include header and footer in a Mustache template

A template for creating web pages is great if you want to integrate front- and backend easy. I have been using Mustache for a while and I’m quite satisfied. It works great with both Dropwizard and Spark

The documentation says how to include a snippet from another template. But searching for it was not that easy.


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