
Testing file input expecting specific output in java
I show you how I test parsing functions in java using file testing; this is where I could add more files for each test case that I want to run. Testing this way makes your workflow quick and easy. Just add a file and then start to solve issues.

Mount a Ceph cluster on Windows 10 using Ceph dokan
We will look into Ceph Dokan which is a new library and command-line client in order to mount your Ceph cluster to a drive letter in Windows 10. Ceph Dokan still very much in beta but it can pretty easily be installed and mounted using some Windows voodoo.

We look into the CRUD concepts using a ORM i wrote called snok
The CRUD concept is pretty integral to the state-management concepts and an ORM is a good way to store information. ORM stands for Object-Relation Mapping and the CRUD concept is the function Create Read Update Delete. Using my ORM Snok we will look at the concepts and talk about the pros and cons of using […]

How to setup wireguard on linux
We look into how to set up WireGuard on a Linux system. In this case, we use Debian in order to create a tunnel between two nodes using WireGuard. The setup is quite easy because WireGuard has strong opinions about what should be available and that means that the setup doesn’t have that many things […]

How to create a qr code generator in java
We look into writing a QR code generator in java from scratch. QR Code has a lot of different technologies and strategies in order to create a readable and unambiguous code. Writing an implementation in Java needs to be done in multiple steps and have a lot of fun and interesting challenges.

How to write an auto clicker in Java
After my kid asked me to download and install an auto-clicker, I saw this as a teachable moment to build one in Java. I could talk about the different concepts Java offers and also explore a new API in the Java API. Source code: package org.ea; import javax.swing.*; import java.awt.*; import java.awt.event.InputEvent; import java.awt.event.KeyEvent; import […]

Looking into a manual upgrade of Ceph to Pacific
Doing a manual upgrade of my Ceph cluster. In the same process, I get the Debian operating system upgraded that my Ceph cluster is running on. The new version of Ceph called Pacific requires some extra measures and when you’ve updated you can’t go back.

Doing an automatic upgrade of ceph cluster using cephadm
In this video, I look into installing and enabling orchestration using cephadm. Then I will perform an automatic upgrade with cephadm. I talk about my findings and go through all the steps.

Talking about lambda functions in java using example
We look into lambda functions in java using example code and understand what functions could help you with. Java has many new concepts that could help you, and lambda is just one of them. For example, you could create Suppliers that give you a value, Consumers that use a value, and then functional interfaces.

Writing a custom log4j appender in java, using RabbitMQ
We look into writing a custom log4j appender in java and how to send you to log messages with an appender to RabbitMQ. Writing a custom appender is challenging due to performance considerations.

Looking at logrotate in debian and timers in general.
We look into logrotate on Debian and figure out how timers actually work with a system with cron installed and configured. This was a bit of a gotcha for me, so hopefully, this will help you when you configure logrotate and want to use the timers in Debian to set a correct time.

Looking into java service provider interface (SPI). Learning by example.
I took a look at the service provider interface in java. This is a needed interface to build simple services using easy building blocks to extend and improve programs or libraries. We will create one example and also look into some tools that use this interface already.