Bug 114512 [working sets] Package explorer should only allow working sets that have an updater installed
I20051101-0010 The package explorer started to support working sets different than the Java working set. However, the package explorer must ensure that an working set updater is installed otherwise it will end up showing stale/bogus content.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/workingsets/WorkingSetConfigurationDialog.java
}
		if (fDownButton != null) {
			fDownButton.setEnabled(canMoveDown());
		}
	}
	
	private boolean areAllGlobalWorkingSets(IStructuredSelection selection) {
		Set globals= new HashSet(Arrays.asList(PlatformUI.getWorkbench().getWorkingSetManager().getWorkingSets()));
		for (Iterator iter= selection.iterator(); iter.hasNext();) {
			if (!globals.contains(iter.next()))
				return false;
		}
		return true;
	}
	
	private void moveUp(List toMoveUp) {
		if (toMoveUp.size() > 0) {
			setElements(moveUp(fElements, toMoveUp));
			fTableViewer.reveal(toMoveUp.get(0));
		}
	}
	private void moveDown(List toMoveDown) {
		if (toMoveDown.size() > 0) {
			setElements(reverse(moveUp(reverse(fElements), toMoveDown)));
			fTableViewer.reveal(toMoveDown.get(toMoveDown.size() - 1));
		}
	}
	private void setElements(List elements) {
		fElements= elements;
		fTableViewer.setInput(fElements);