class CostCalculationException extends Exception$\{\}$

class Item $\{$

public void calculateCost$()$ throws CostCalculationException $\{$

$//...$

throw new CostCalculationException$()$;

$//...$

$\}$

$\}$

class Company $\{$

public void payCost$()\{$

new Item$().$calculateCost$()$;

$\}$

$\}$