Eclipse projects get compile errors, cant find org.eclipse.* or org.osgi.*

Sometimes I get compilation problems with my Eclipse projects, they suddenly cant find any org.eclipse.* packages and therefore nothing compiles. It doesnt happen that often, so I havent been able to properly determine the cau开发者_StackOverflow中文版se, but this last time it I installed and then uninstalled some big features.

There is a workaround for it though, delete the projects from workspace and then reimport them.

Anyone else recognize this and know an easier solution?

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It should be like my recent problem, when eclipse do not see java.lang.Object. I usually just put a space into the projectroot/.classpath somewhere outside xml tags, and it solves the problem. If not try .project file as well. This is only a workaround, but usually works.