if ( error != null ) { NamingException total = new NamingException( "Encountered failures " + "while performing a close() operation on backing stores" ); total.setRootCause( error ); }
    public void close() throws NamingException    {        Iterator list = this.backends.values().iterator();        while ( list.hasNext() )        {            BackingStore store = ( BackingStore ) list.next();            store.sync();            store.close();        }        s_singleton = null;    }