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I installed the groovy eclipse plugin several times and I always end up with a useless eclipse.
Eclipse version: Indigo, 3.7.2
OS Ubuntu 12.04
1. open a java file and an ant build file in eclipse and check that the corresponding editors are working
2. installation of groovy plugin via update site
3. restart of eclipse after sucessful installation
4. in the still open editor tabs, neither java nor ant files are dsiplayed due to missing editors
5. when trying to open the java perspective, it is no longer available.