And even then, .NET isn't an alternative to JEE. It's a lot broader. .NET is an alternative to the entire Java platform, JSE, JME, AND JEE.
I fear that the move to open source the platform will indeed mean that Java will soon enter a decline. Whether .NET will benefit from that or not remains of course to be seen, it might well be that some other technology instead takes it place, like Python or Ruby (which are available on more platforms than is .NET, important for people/companies employing non-Windows server architectures with Java applications).
But at the moment I don't see any strong move in progress away from Jave and towards .NET. There is some drift, but that goes both ways (and quite a few people happily use both together).
And to further add in another opinion on top of Jeroen's...
I think there's also an issue of where we all think the two platforms are going. Certainly, I see room for both of them in the marketplace (and I'd be less than honest if I didn't admit that I'm also working on learning C# as the moment, as the platform we're using in the office exposes APIs for both Java and .Net). I think there's going to be some move towards the center, as both begin to adopt means for doing similar tricks, but there are also areas where the two do not even begin to approach each other.
I don't even think it's going to be a move to/from one to the other - I think it's going to turn into a gradual adoption of the same paradigm that's existed for a while - the proper tool for the proper job, with both architectures carving out niches...
Theodore Jonathan Casser
SCJP/SCSNI/SCBCD/SCWCD/SCDJWS/SCMAD/SCEA/MCTS/MCPD... and so many more letters than you can shake a stick at!
..And more often that not, we see top management voting for .NET because using Java technolgies efficiently needs a lot of expertise and skill, which unfortunately is short in supply amongst most companies (at least among the smaller/medium shops).
People in the management want to see results fast and it that's the case .NET is the way to go but I would STRONGLY vote for JAVA technologies for all their strengths.
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