Since Sun’s announcement this week of their concrete plans to Open Source the javac compiler and the HotSpot VM, I expect there has been some panic in some circles discussing what this means for current and future Java developers and projects.
As summarized in this news item on news.com, the impact is likely to be neglible to end-user developers, and current and/or future projects using Java. The main difference will be that you have the option to commit features and/or bug fixes back to the source. In reality, a much higher percentage of users of open-sourced software just use the software as it is – only a small number ever get involved in the ‘nuts ‘n bolts’ and become code submitters.
This should be seen as a good thing for Java as it will increase choice (who’s VM implemenation do I want to use?), and through competition keep people from becoming halfhearted about their VM implementation. Even up until now there have been commercial VM implementations from different vendors (BEA’s JRockit, IBMs VM), as well as ‘based-on’ Java implementations, which for legal reasons are not allowed to call themselves ‘Java’, but are definitely based on the language (eg Waba VM for handheld devices) and even based on the Java platform such as Microsoft’s Common Language Runtime (CLR), which is arguably the same concept as the Java VM, together with the C# language and a number of other languages which can be compiled to run on the same CLR.