It’s pretty common when doing Java development to need mutiple versions installed alongside each other. With Brew and Jenv, switching Java versions between projects becomes easy.
If you’re currently executing your target platform that you build your product from instead of a properly installed Eclipse, you will have troubles when you upgrade. Eclipse 3.5 and above don’t count plug-ins as installed by simply unzipping - the configuration meta data must refer to them. The best way is to download a complete Eclipse and unzip this somewhere on your build server, instead of assembling it from components at build time. Guess we should have been doing this all along.