CargoBatch cb = (CargoBatch)it.next();
CargoBatch cb = (CargoBatch)((Entry) it.next()).getKey();
    public String toString() {        String s = "CargoBundle {\n";        Iterator it = this.cargoBatchIterator();        while (it.hasNext()) {            CargoBatch cb = (CargoBatch)it.next();            s += this.getAmount(cb) + " units of cargo type " +            cb.getCargoType() + "\n";        }        s += "}";        return s;    }