Yet again I've java in my studies at ITU. The current assignment Peter, Thomas and I are working on is to implement an assistant that helps a user solve the classic N-Queens problem using Reduced ordered Binary Decision Diagrams (RoBDDs or simply BDDs).
There's many(!) ways to solve that problem, but using BDDs does seem like a very intriguing approach. The only problem: it requires a BDD engine. We could of course write our own (and actually I'm currently working on that), but in the assignment we were given, there was actually a fully functioning BDD library ready for us to use. Only, it was in java... (NOTE: I don't have any problem with java and I'm not religious in any ways, but usually .NET is my weapon of choice).
"No problem, we'll just use J# to handle it like last time" was the initial reaction.
But, alas, the library was already a compiled jar, no source included. Naturally we could get all the source from sourceforge and port it to J#, but the time seemed right to try a new clever approach!
Luckily Peter found the right solution: Enter IKVM! IKVM is a great set of tools to interact between java and .NET and it works like a charm.
The two main tools is a command-line program that allows you to run compiled java files in .NET instead of java's virtual machine. The other tool that proved to be really useful to us, will allow you to take a JAR and transform it into a .NET DLL.
All I had to do was to call it command-line with the name of the JAR file and the name of the .NET output file, and run it - and in no time I had a working .NET dll that I could reference directly in my .NET projects.
In order for the referencing programs to work though, it's important to have two of the IKVM dlls' included in the "bin" folder or in the GAC (namely the "IKVM.GNU.ClassPath.dll" and "IKVM.Runtime.dll").
Great work, IKVM guys. Keep doing your magic!
And the programming assignement? Well, here is how far we've gotten so far. Keep in mind that it's work in progress. After the hand-in deadline I'll make a new post about how we did it.
I'm also considering trying out other of the known approaches to solve the same problem and comparing them. Drop a comment if you'd be interested in knowning what works best :-)