Bug 28244 Edit->Undo / Refactor->Undo don't play well together
reproducible in I20021210 with the following steps and code: - select "b + c" - extract local - edit->undo - refactor->undo public class Test { public Test() { int a= 1; int b= 2; int c= 3; int d= a + b + c; } }
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/actions/ActionUtil.java
return true;
			
		if (checkJavaElement((IJavaElement)element))
			return true;
		MessageDialog.openInformation(shell, 
			ActionMessages.getString("ActionUtil.notOnBuildPath.title"),  
			ActionMessages.getString("ActionUtil.notOnBuildPath.message")); 
		return false;
	}
	private static boolean checkJavaElement(IJavaElement element) {	
        
        if (element.getElementType() == IJavaElement.JAVA_PROJECT)
            return true;
		IJavaProject project= element.getJavaProject();
		try {
			if (!project.isOnClasspath(element))
				return false;
			IProject resourceProject= project.getProject();
			if (resourceProject == null)
				return false;
			IProjectNature nature= resourceProject.getNature(JavaCore.NATURE_ID);
			
			if (nature != null)
				return true;
		} catch (CoreException e) {
		}
		return false;
	}
}