purgeThreatVariationCache(  tm_change.getRemovedAssets() );
purgeEventCollectionsCache(  tm_change.getRemovedAssets() );
    public void handleThreatModelChange( ThreatModelChangeEvent tm_change )            throws BelievabilityException    {        if ( tm_change == null )            throw new BelievabilityException                    ( "AssetTypeDimensionModel.handleThreatModelChange()",                      "Found NULL for threat change object." );        ThreatModelInterface threat_model = tm_change.getThreatModel();                // We deal with the removed and added assets the same.  Just        // purge the cahce to force it to be recalculated.        //        purgeThreatVariationCache( tm_change.getAddedAssets() );        purgeThreatVariationCache(  tm_change.getRemovedAssets() );            } // method handleThreatModelChange