The client I work for at this time is leveraging Axon 3. The events are stored in a PostgreSQL database. PostgreSQL uses a thing called TOAST (The Oversized-Attribute Storage Technique) to store large values. From the PostgreSQL documentation: “PostgreSQL uses a fixed page size (commonly 8 kB), and does not allow tuples to span multiple […]
How to send your Spring Batch Job log messages to a separate file
In one of my current projects we’re developing a web application which also has a couple of dozen batch jobs that perform all sort of tasks at particular times. These jobs produce quite a bit of logging output when they’re run, which is important to see what has happened during a job exactly. What we […]
Writing less code
Have you had that feeling that you have to write too much code to build simple functionality? Some things just feel repetitive, they feel you should be not have to write them yourself, instead a framework should make your life easier. Recently I’ve been building a project in Java/Spring, and after some time I started wondering […]
Personalised city trip itinerary using integer linear programming
Case As a research project I have developed an itinerary service. The idea started when I was doing a hackathon with colleagues for the city of Amsterdam (see earlier post). I wanted to recommend an itinerary to a tourist visiting the city of Amsterdam. Furthermore, I wanted to make the itinerary based on the user’s interests to recommend […]
Controlling Java with the Leap Motion
Leap Motion Controller The Leap Motion Controller is a device that uses two cameras to track the hands and fingers. This makes it possible to use gestures for controlling the computer or applications. It is possible to buy or download applications through the Leap Motion app store, but there is also an SDK for different […]
City-wide crowd management in Amsterdam
As most residents and visitors of Amsterdam know, every year more people are visiting Amsterdam, city wide events like GayPride, Koningsdag and MuseumNacht are getting bigger and more frequent, putting more strain on the city’s infrastructure and all people living in the city center. That’s why this November 7th, Amsterdam Marketing organized the Museumn8 hackathon […]
Recognizing commercials using the Alphonso API
Liberty Global organized the Hack & Play Appathon in Ziggo dome on September 15th and 16th. More than 20 teams of hackers, designers and programmers were invited to create an app or a game for the Liberty Global product Horizon set-top box. Team Trifork joined with Dennis de Goede (Design & Frontend), Tony Abidi (Devops) […]
A wrinkle in time
I clearly remember the morning of Sunday July 1, 2012, almost three years ago. I was at church, actually, when I got a call from one of our clients: “The website doesn’t seem to be working.” All I could check at that point was that, indeed, the website was not responding. So I called our sysadmin, who […]
Documenting your REST APIs
Whenever you deliver some API that is to be consumed by another party, you will get the inevitable question of providing documentation. Probably every developer’s least favorite task. In Java there is javadoc, but that doesn’t cut it if you are delivering a Web Service API. In that realm we already know WSDL for SOAP based […]
RUNNING CUSTOM “LINT” CHECKS ON YOUR ANDROID BUILDS
In this post, I’ll share a very simple tip on how to add very simple custom checks of your Android source code to your Jenkins build server, but the tip should be very easily ported to other build servers too. What? Most developers know of Lint checks as something which perform some kind of static […]