Author Archives: Jan Sipke

Installing Sun JDK 6 on Ubuntu 10.04

Posted on 27/05/2010 by Jan Sipke

The Sun JDK can be installed on Ubuntu by adding a repository and installing with apt-get. The following works with the latest versions of both at the time of writing: Sun JDK 6 update 20 Ubuntu 10.04 sudo add-apt-repository “deb … Continue reading →

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Getting CPU, memory, disk and network metrics from XenServer

Posted on 08/05/2010 by Jan Sipke

In a previous article we looked at getting CPU and memory metrics from XenServer. As noted in that article, as of version 5.5 of XenServer, the preferred way of getting virtual machine metrics is through HTTP calls to get RRD … Continue reading →

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Using Google Visualization API with own data source

Posted on 29/03/2010 by Jan Sipke

The Google Visualization API allows you to create charts and maps based on data you provide. This data can be in a Google Spreadsheet or be something you provide yourself. The visualizations themselves are mostly written in Javascript, although there … Continue reading →

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Creating web charts using Open Flash Chart

Posted on 24/03/2010 by Jan Sipke

Open Flash Chart gives you the possibility to have Flash based charts on your website without the need to know Flash. All it takes is a JSON file that describes the chart. This JSON file can be a static file … Continue reading →

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Google Maps icons and circles

Posted on 07/03/2010 by Jan Sipke

It is quite easy to add content to Google Maps by using the API. In this article we will use some icons to mark points of interest and use polygons to emulate circles around a marker. We want to give … Continue reading →

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Getting XenServer VM metrics in Java

Posted on 03/03/2010 by Jan Sipke

XenServer is a product of Citrix that can run virtual machines on a set of physical hosts called a pool. There is an API that allows you to create programs that interact with the XenServer pool. There are some function … Continue reading →

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Using OpenJMS within Eclipse

Posted on 19/02/2010 by Jan Sipke

OpenJMS allows you to use the Java Message Service (JMS) without a full-fledged Java Enterprise Edition container. It is an open source implementation of the JMS 1.1 specification. We start by installing and starting OpenJMS. On Windows this is done … Continue reading →

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Using the sage mathematical software system

Posted on 04/01/2010 by Jan Sipke

This article describes the installation and simple usage of the Sage mathematical software system. Sage is free, open-source math software that supports research and teaching in algebra, geometry, number theory, cryptography, numerical computation, and related areas. We start by installing … Continue reading →

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Examples of public SOAP web services

Posted on 20/11/2009 by Jan Sipke

In the previous article we showed how to use the suds library in Python to access SOAP web services. Here are some extra examples of public SOAP web services. Some of the outputs are edited for readability. We start with … Continue reading →

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Python SOAP client with suds

Posted on 20/11/2009 by Jan Sipke

The library suds allows Python to make SOAP calls (that is, Python is the web service client). We start by installing the suds library on an Ubuntu machine. The Python setuptools are needed to install suds. sudo apt-get install python-setuptools … Continue reading →

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