Class PhoneCard

java.lang.Object

PhoneCard

Direct Known Subclasses:

SmartANZAsia10Card

public abstract class PhoneCard
extends Object

An abstract class that encapsulates information about phone cards. The information includes the card number, password, and balance.

Author:

CSE1030

Constructor Summary

Constructors

Constructor and Description
PhoneCard(long number, int password, double balance) Create a phone card with the given number, password, and balance.

Method Summary

Methods

Modifier and Type	Method and Description
abstract Set<CallZone>	allowedZones() Get the set of call zones that can be called on this phone card.
boolean	charge(int minutes, CallZone zone) Charge a call of the given number of minutes to the zone.
abstract double	costPerMin(CallZone zone) Get the cost per minute of a call to the argument zone on this phone card.
abstract void	deductWeeklyFee() Deduct the appropriate weekly fees from the card's balance.
boolean	equals(Object obj) Indicate whether some other object is "equal to" this one.
double	getBalance() Get the balance of this phone card.
int	getLimit(CallZone zone) Get the number of minutes allowed for a call to zone given the balance.
long	getNumber() Get the number of this phone card.
int	getPassword() Get the password of this phone card.
abstract boolean	isAllowed(CallZone zone) Check whether a call to the argument zone is allowed for this phone card.
void	setBalance(double balance) Set the balance of this phone card.
String	toString() Create a string representation of the object.

Methods inherited from class java.lang.Object

getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

PhoneCard

public PhoneCard(long number,
         int password,
         double balance)

Create a phone card with the given number, password, and balance.

Parameters:

number - the phone card's number.

password - the card's password.

balance - the card's balance.

Precondition:

number and password are positive and balance is non negative.

Method Detail

getNumber

public long getNumber()

Get the number of this phone card.

Returns:

the number of this phone card

getPassword

public int getPassword()

Get the password of this phone card.

Returns:

the password of this phone card.

getBalance

public double getBalance()

Get the balance of this phone card.

Returns:

the balance of this phone card.

setBalance

public void setBalance(double balance)

Set the balance of this phone card.

Parameters:

balance - the balance to set.

Precondition:

balance is non negative.

isAllowed

public abstract boolean isAllowed(CallZone zone)

Check whether a call to the argument zone is allowed for this phone card.

Parameters:

zone - the zone to check.

Returns:

true if calls to this zone is allowed for this phone card, and false otherwise.

allowedZones

public abstract Set<CallZone> allowedZones()

Get the set of call zones that can be called on this phone card.

Returns:

the set of call zones.

costPerMin

public abstract double costPerMin(CallZone zone)

Get the cost per minute of a call to the argument zone on this phone card.

Precondition:

a call to zone is allowed for this card.

Returns:

the cost per minute.

getLimit

public int getLimit(CallZone zone)

Get the number of minutes allowed for a call to zone given the balance. This method returns the maximum number of minutes that can be charged for a call to the argument zone given the card's balance (truncated down to the next integer).

Parameters:

zone - the zone that the call is going to.

Precondition:

a call to zone is allowed for this card.

Returns:

the maximum number of minutes for a call to the given zone.

charge

public boolean charge(int minutes,
             CallZone zone)

Charge a call of the given number of minutes to the zone. This method tries to charge a call to zone with the given number of minutes to the card; if the balance is sufficient to cover it, it returns true and if the balance is not sufficient, it leaves it unchanged and returns false.

Parameters:

minutes - the number of minutes to charge.

zone - the zone that the call is going to.

Precondition:

minutes is positive and a call to zone is allowed for this card.

Returns:

true if the balance was sufficient to pay for the call, and false otherwise.

deductWeeklyFee

public abstract void deductWeeklyFee()

Deduct the appropriate weekly fees from the card's balance. If the balance is insufficient, the balance becomes 0.

equals

public boolean equals(Object obj)

Indicate whether some other object is "equal to" this one. The result is true if and only if the argument is not null, has the same class as this object, and both objects have the same number.

Overrides:

equals in class Object

Parameters:

obj - The object to compare with.

Returns:

true if the cards' numbers are equal; false otherwise.

toString

public String toString()

Create a string representation of the object. The string is "card no " followed by the card's number followed by " has a balance of " followed by the card's balance.

Overrides:

toString in class Object

Returns:

the string representation of the object.