Bug 127861 [DataBinding] Mark API provisional
bundles/org.eclipse.jface.databinding/src/org/eclipse/jface/databinding/updatables/ConvertingSet.java
/**
     * Creates a new set whose elements are the result of applying the given function
     * to all the elements in the input set. 
     * 
     * @param input
     * @param f
     */
    public ConvertingSet(IReadableSet input, IUpdatableFunction f) {
        super();
        this.input = input;
        this.func = f;
    }
    public boolean isStale() {
        return func.isStale() || input.isStale();	
    }
    
	private void processAdds(Collection added) {
    	
    	
    	if (func == IdentityFunction.getInstance()) {
    		fireAdded(added);
    		return;
    	}
    	
    	ArrayList adds = addMappings(added);
        fireAdded(adds);
    }
	private ArrayList addMappings(Collection added) {
		ArrayList adds = new ArrayList();