JProfiler is a Java profiler which can give you insight into what a running application is doing: which methods are consuming the most cpu, how many objects are created, etc. Jprofiler also shows you information about jdbc calls and sql statements executed by your java application.
Setting up Jprofiler to profile a Mendix runtime is easy, you can start profiling a running Mendix runtime, without reconfiguration or restarting the application.
The installation guide provides a (more...)
After reading this fine summary of the history of Python 3 by Nick Coghlan I was inspired to update as many of my half finished projects and miscellaneous scripts as possible. Then I looked up and I had lost several hours of my life. To save random internet strangers from the same pain as I experienced here is a catalogue of problems and how I solved them.
tl;dr – Python 3.3 on Ubuntu 12. (more...)
I’ve been trying to install open source software. In this case an application called Moodle. I followed the instructions to install it on an Ubuntu Server vm but they were missing a couple of key points.
After installing the Moodle package (under “Moodle Installation” in the instructions) you need to (more...)
Tijdens het LAC-2013 heb ik een presentatie verzorgd over Dynamische Architectuur Visualisatie. Tijdens deze presentatie heb ik laten zien hoe ik schetsen in SVG formaat gebruik als visuele ondersteuning van een presentatie. De svg versie van deze presentatie zie je hieronder. De volgende pagina biedt de mogelijkheid om slides van (more...)
The following is only relevant if you run Mendix on-premises. If you do, you probably have standard monitoring tooling that you use to monitor all your applications.
For java applications most monitoring tools provide a way to hook into JMX to get information about the application. The following describes how (more...)
Selenium is a useful tool for automating functional tests. In this post i’ll show you some tips and tricks about using Selenium IDE with Mendix. Selenium IDE is a Firefox plugin that enables you to record whatever you are doing in Firefox, so that you can repeat these steps as (more...)
I had the great privilege to present this weekend at PyCon Australia 2013. My talk was originally titled "Why I Use py.test and Maybe You Should Too" but as I wrote the paper and accompanying slides I realised that it should really have been called "How to Start Unit (more...)
I think this is not mentioned in Vojta’s testacular video, or maybe I missed it, but i had to install JetBrain’s chrome debugger plugin to be able to debug tests run with Karma in Webstorm.
The steps i used to get it to work:
Good news, I am back in blogging :) In recent years I have spent my time primarily on eazyBI business intelligence application development where I use JRuby, Ruby on Rails, mondrian-olap and many other technologies and libraries and have gathered new experience that I wanted to share with others.
Recently I did eazyBI migration from JRuby 1.6.8 to latest JRuby 1.7.3 version as well as finally migrated from Ruby 1.8 mode to Ruby 1.9 mode. Initial migration was not so difficult and was done in one day (thanks to unit tests which (more...)
There are a lot of people who think camera’s in tablets are a bad idea. “Nobody should be allowed to take pictures with a large tablet in front of their face.”
But if you can think outside of the traditional camera box for a moment, and start to think what’s possible if you combine a really portable computer with a decent camera, you’ll soon see interesting new possibilities.
Just a couple examples:
While converting my old wordpress blogposts to markdown i read some of my old
posts. For example, here is what i wrote when Apple launched the iPhone in 2007:
In a couple of years mobile phones will be powerful enough to replace
laptops for most common computing usages. You won’t need a separate laptop.
You walk around with your mobile phone, in the office or at home you put it
in a docking station, attach a keyboard and a bigger display, and you have
all the computing power you need.
Some news this last week indicates we’re getting close (more...)
Work in progress
I’m a slow mover here, far behind the hype-curve, but this blog is currently being moved to jekyll. The following are some notes and links from this process.
Reasons to migrate:
- Cheaper hosting - this blog is currently hosted on DreamHost. By migrating to a static site using Jekyll, cheaper options become available, for example Amazon S3 or Github.
Ik kwam vanochtend op Google+ een interessante presentatie van Magaret Leibovic tegen waarin ze onder andere de tools in firefox bespreekt die je kunt gebruiken voor het debuggen van web applicaties op een smartphone.
Safari biedt vergelijkbare tooling om webapplicaties op een iPad of iPhone te debuggen. Deze heb ik (more...)
On my morning commute today I realised that I am actually living in the future. I remember when I got involved in the PythonCard project 10 years ago one of the major questions on the mailing list was why we were building a GUI toolkit when the future was the web. It wasn’t true then but I think that it is now.
Why do I think we have moved now? It is in large part thanks to a book I have started reading called Python for Data Analysis. I have a copy of the book in ePub format and wanted (more...)
This site may not be available for various periods over the next couple of days as I move it lock, stock and barrel to a new web host. It has been a good few years at Cornerhost but it’s time to move. After an exhaustive search I’ve signed up at WebFaction and will be up and running on their servers in no time at all.
This does mean that email reception may be spotty as I migrate. In the rare event that you send me an email and I don’t reply please accept my apologies. Then resend your email. See (more...)
It started with a tweet from Tim O’Reilly. He mentioned a quote that I’m very familiar with – “Data matures like wine, applications like fish”. When I read it I wondered if it was anything to do with. His tweet linked to a blog post called the 11 best data quotes from the DataMarket blog. On that list (which I highly recommend reading) the quote was tentatively attributed to me based on a write up of my 2009 OSDC presentation entitled “Change Bad!”.
I’d like to take the credit for this, I really would. But I can’t. I did (more...)
I am very excited to announce that EclipseLink 2.4.0 is now available for download.
Highlights of this release include:....
Java Persistence units can now be exposed over REST using either JSON or XML media.
Tenant Isolation - Table per tenant
Developers can design and deploy applications where their persistent entities are stored in separate tables per tenant.
This release introduces EclipseLink's NoSQL support for MongoDB and Oracle NoSQL.
EclipseLink MOXy can now be used for the marshaling and unmarshaling of JSON object. This is core infrastructure to the JPA-RS (more...)
I have been interested in business intelligence and data warehouse solutions for quite a while. And I have seen that traditional data warehouse and business intelligence tool implementations take quite a long time and cost a lot to set up infrastructure, develop or implement business intelligence software and train users. And many business users are not using business intelligence tools because they are too hard to learn and use.
Therefore some while ago a had an idea of developing easy-to-use business intelligence web application that you could implement and start to use right away and which would focus on ease-of-use (more...)
As of EclipseLink Indigo (2.3.0) you have been able to use the @Multitenant feature
to share a database schema between multiple tenants. Did you know that you can also use this feature together with the Oracle Virtual Private Database (VPD) support that has been available in EclipseLink since version 1.0?
This powerful combination of features allows for the shared tables to be managed directly on the database, and for inserts to be automatically associated with the proper client. Any SQL executed by EclipseLink (even if EclipseLink did not generate it - ie native queries) will go through (more...)
I just released Oracle enhanced adapter version 1.4.0 and here is the summary of main changes.
Rails 3.1 support
Oracle enhanced adapter GitHub version was working with Rails 3.1 betas and release candidate versions already but it was not explicitly stated anywhere that you should use git version with Rails 3.1. Therefore I am releasing new version 1.4.0 which is passing all tests with latest Rails 3.1 release candidate. As I wrote before main changes in ActiveRecord 3.1 are that it using prepared statement cache and using bind variables in many (more...)