Yesterday I held a short seminar (2 hours) on Open Source and .NET for the Systems Development team at Cybercom Sweden East. The seminar was split into three separate presentations, I will try to give a short summery of them here. At the end of the post I will post links to the powerpoints and application examples.

Open Source and .NET 

This presentation covered a short introduction to open source. I began with explaining the most common licences (GPL, LGPL, Apache) and then moved on to list a few interesting framework and development tools. But mostly it was about why I think utilizing open source is something that we as .NET developers need to be better at, and why this will be very important if the .NET platform is going to stay competitive.

I have never worked professionally as a java developer but my understanding is that tools like Eclipse and frameworks like Struts, Hibernate and Spring are used to a very a large extent (30 - 70% according to some studies). And what types of platforms do java applications run on? They usually run on an open source OS and use an open source web server (Apache) or application server. This means that the devolvement environment, tools and frameworks are largely based on open source software.

I think this fact contributes to the mindset of java developers and project managers to actively search for, and be more open to, open source solutions. I feel that many .NET developers are prone to constantly reinvent the wheel, for example by creating their own logging framework or a basic data layer tool without ever searching for existing alternatives, be that open source or commercial.

Open Source benefits

I also talked about some of the benefits I see with open source frameworks compared to Microsoft's offerings. One of the main things I mentioned here was innovation, I think that a lot of innovation in development methodologies (TDD), design, frameworks and tools are coming to large extent from the open source community. The fact that open source software starts without commercial aspirations or requirements results in software that is more focused on solving real problems and less on flashy designers.

Open Source problems

The major problem I see with open source is the lack of commercial support services. I don't see this personally as a problem but as a problem when trying to sell open source solutions to management. There are many companies that are offering training and support for open source frameworks and tools on the java side but very few for the .NET equivalents. I think this point is also one of the major reasons why .NET  is so behind java when it comes to open source adoption. The lack of commercial support is something I partly blame on Microsoft who instead of promoting and supporting open source actively compete with it.

Open Source trends

I ended the presentation by showing some statistics from the IOUG Open Source 07 Report. This report really shows how much open source software is currently being used by big enterprise companies (almost exclusive non .NET software) and that this is an increasing trend. Just between 2006 and 2007 the increase in the use of open source software was 26%. The report also showed the reasons why open source software is being used. The two main reasons were cost savings and no proprietary vendor lock-in.

Not to be misunderstood, I am not an open source fundamentalist, I just think there is a lot of value in some open source frameworks and tools and I think .NET developers in general (maybe not those who happen to read this blog) should utilize this resource more. 

Log4Net & NHibernate

I also held a presentation about Log4Net and an hour long presentation about object-relational mapping with NHibernate which included a short live coding demo. 

Here are the powerpoints (they are in Swedish):

I also made some sample applications:

I wanted some code in this post so here is snippet from the NHibernateDemo application that shows how simple property projection is with the NHibernate Critiera API:

public IList<string> GetAllBlogOwnerNames()
  return Session.CreateCriteria(typeof(User))