I've got an article on that at http://www.devx.com/interop/Article/19845[^]. It's a new edition of an article[^] I wrote for CodeProject alost two years ago, which was a rewrite of an article I wrote about a year before that. Sure, there are already bridge products that have been out for a couple years, but these articles will tell you how it's done (using JNI and, optionally, COM - though not required if you P/Invoke native functions from the JNI library you'd have to write). The DevX article I linked first goes into greater depth about calling Java methods from the JNI DLL.
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