if ( ( reference == null ) || ( referee == null ) )
{
return;
}
SchemaObjectWrapper wrapper = new SchemaObjectWrapper( reference );
Set<SchemaObjectWrapper> uses = getUsing( reference );
if ( uses == null )
{
uses = new HashSet<SchemaObjectWrapper>();
}
uses.add( new SchemaObjectWrapper( referee ) );
// Put back the set (this is a concurrentHashMap, it won't be replaced implicitly
using.put( wrapper, uses );
}