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Title: Case Study:

1

Case Study
Programming An ATM

2
HW 4

3 x 3 array
For player computer generate randoem variable
between 1 and 3
import java.util.Random
Random rand new Random()
int i rand.nextInt(3)
i between 0-2 uniformly distributed random
integer

3
HW 4

Wining condition
If
Two states
Current
Previous
do
when enrted to loop make curent state privous
After a play make new stae current
Check wining conditton
If someone wins record previous
Record previous state
Eles
While(stoping condition)

4
The ArrayList Class

Array store objects but
Once an Array is created its size is fixed
Java ArrayList class to store unlimited number of
objects

5
Some Methods of the ArrayList Class

ArrayList()
Create an empty list
void add(Object o)
Append a new element o at the end of the list
void add(int index, Object o)
Add a new element o at the specifed index to the
list
void clear()
Removes all the elements from the list
boolean contains(Object o)
Returns true if the lsit contains Object o

6
Some Methods of the ArrayList Class (cont.)

Object get(int index)
Returns the element from the list at the
specified index
int indexOf(Object o)
Retuns the index of the first matching element in
the list
boolean isEmpty()
Returns true if the list is empty contains no
elements
int lastIndexOf(Object o)
Returns the index of the last matching element
boolean remove(Object o)
Removes the element from the list

7
Some Methods of the ArrayList Class (cont.)

int size()
Returns the number of elements in the list
boolean remove(int index)
Removes the element at the specifed index from
the list
Object set(int index, Object o)
Sets the element at the specified index

8
Comparing Array and ArrayList

Creatng an Array/ArrayList
Object a new Object10
ArrayList list new ArrayList()
Accesing an element
aindex
list.get(index)
Updating an element
aindex London
list.set(index,London)

9
Comparing Array and ArrayList (cont.)

Returning size
a.length
list.size()
Adding a new element
-
list.add(London)
Inserting a new element
-
list. add(index,London)

10
Comparing Array and ArrayList (cont.)

Removing an element
-
list.remove(index)
list.remove ( London)
Removing all elements
-
list.clear()

11
An Example Program

import java.util.ArrayList
public class ArrayListTest
public static void main(String args)
ArrayList list new ArrayList()
list.add("Ankara")
list.add("Istanbul")
list.add("Izmir")
System.out.println("size"list.size())
int i list.indexOf("Ankara")
System.out.println("index of Ankara"i)
System.out.println("index of Ankara"list.indexOf
("kjk"))
Integer j new Integer(2)

12
An Example Program (cont.)

list.add(j)
System.out.println("size"list.size())
int k 2
list.add(k)
System.out.println("size"list.size())
X x new X()
list.add(x)
System.out.println("size"list.size())
System.out.println("index of
x"list.indexOf(x))
X y (X)list.get(5)
System.out.println("value of y.a"y.a)

13
An Example Program (cont.)

class X
public double a 10

14
An ATM Example

The customer of a bank connects to her bank
accounts
Select an account a customer may have more then
one account
Prform opperations
see balance
Deposit money
Withdraw money
Transfer money to another account
Cancel the oppertations
Using GUIs and database connecti

15
What are classss?

Classes
ATM, customer, Account, Connection, GUI
Design principle
Seperate clases
Control classes ATM
Entities customer, account, connection
Boundry CUI

16
What are classss?
Account
Frame
Atm
Connection
Customer
17
User to Atm class

The user has some request from the system
Enter PIN
Select an account
Select opperation
Enter or select amount of money to withdraw
The user should get messages from the system
Not enough oney to withdraw
The account not fount (in case of transfer)
User request taken from the GUI are sent to Atm
the control class
Atm class calls the withdraw method of the
account class
Send the information to the GUI and the database

18
Starting the program

When the program starts
A start frame of the ATM is presented to the user
In reality the user inserts her card
The card is identified
Read the card number
Search the database of customers
This is a ATM simulation
Inserting the card is represented as entering the
card number from the keypad
Then enter the PIN (Personel Indentification
Number) from the keypad

19
Starting the program (cont.)

These information is taken from the GUI is send
to the Atm class
The Atm class
Connect to the database
To check whther there is such a customer
if true
Creates a customer object name ,
Get the accounts information from the database
Send this to the GUI
if false
Ask PIN several times

20
Selection of the account

The user selects an account
Account number is sent to the Atm class
Creats the account class
There are both saving or chacking accounts
After selecting an account
GUI changes
On the left and right sides show the opperations
Balance, withdraw, deposit, transfer, cancel

21
Withdraw opperation

When the user selects withdraw
There are predetermined amounts
20,50,200,300, and others
Deermine the amount and send to Atm
if the other button is clicked
Enter the amount from the keypad then press Enter
button
GUI send the amout of money to be withdrawn trom
the accont to the Atm class
The Atm calls
Check the balance of the account
if balacne gt amount
withdraw method of the account
Update the database
Send a message to the user
if not
Send a message to the user

22
Deposit opperation

Similar to withdraw
Amount of money deposited is entered from the
keypad and press the Enter button
No special choises are presented to the user
Note this is just a simulation of the ATM
In reality the physical amont of money is put to
an envelop and inserted into the machine
Here it is entered from the keypad

23
Transder of Money

Asks the user
the account number to which money will be
trnsfered
And amount of money to be transferd
The prohlems are
Account mey not be found
The balnce may not be enough to meke this
transfer commussions if any
So the Atm class
Checks whether there is such an account
And balnce is greater then the money transfered
if so
Withdraw moeny from the account
Updates the transfer account
Send a mesage to the user that tranfer is made
succesfully
If not
Send a message to the user indicating that
transfer in not succesul

24
Cancel button

When pressed cancel the opperations ar cenceled
the ATM returns to the first state

25
GUI

A class that extends from JFrame
Border layout
North infromation present information to the
user
South keypad
Cener textfield and a label
Amount of moeny, PIN.,,
East and West opperations of choises
Withdraw, deposit, transfer, cancel
50,100,200, others
Keypad
All numbers are enterd from the keypad and
appears in a textField

26
AtmTest class

public class AtmTest
public static void main(String args)
Atm atm new Atm()
// end method main
// end class AtmTest

27
The control class

Main task
Create other objcect from other classes
Account account, DbConnection dbconnection
Frame frame
interract with the boundary object frame
Updat the database
Ubdate the temporary account object

28
The control class

In its constructor
Create the frame object boundary class
Get information from teh user
Present information to the user
Create the database connection
Create an account

29
The control class - Atm

class Atm
DBConnection dbConnection
Account account
Account account2
boolean tF
double balance
String accountNo
String name

30
constructor

/
Create the frame
And database connection objects
Note in the frame object since it repeatedly
calls the Atm (control) class methods there
should be a reference to atm-
setContrl(Atm a) method does this
/

31
constructor

public Control ()
Frame framenew Frame()
frame.setControl(this)
frame.setDefaultCloseOperation(JFrame.EXIT_O
N_CLOSE)
frame.setSize(500,400)
frame.setVisible(true)
dbConnection new DBConnection()

32
Method getPassword

/
when the user enters a PIN from the GUI
call the method to send this information to the
control class which chacks the database to see
whether there is such a customer
if found
returns true and
get the account infrmation from the
database
create an internal account object
else
return false
/

33
Method getPassword

public boolean getPassword(String sifre)
tFdbConnection.getPassword(sifre)
if (tF)
getDbBalance()
getDbAccountNo()
getDbName()
createAccount()
return tF

34
Method getPassword

/
these methods get information from the database
about the account

public double getDbBalance()
balanceDouble.parseDouble(dbConnection.getInfo(
"miktar"))
return balance
public String getDbAccountNo()
accountNodbConnection.getInfo("Noo")
return accountNo
public String getDbName()
namedbConnection.getInfo("soyad")
return name

36
Methods getting infromation from athe internal
accout object

These methods
Creatre teh account object
Get its instance variables
AccountNo
Account name
And balance
And store in contol object to be used

public void createAccount()
account new Account (name,accountNo,balance)
public double getBalance()
return account.getBalance()
public String getAccountNo()
return account.getAccountNo()
public String getName()
return account.getAccountName()

38
Withdraw and deposit methods

First updata accont object in memory
For withdraw
if true enough money in the account
updata the database
return true to the caller
else not enough money in the account
no connection to the database is needed
return false
For deposit
Updata the account object and database
respectively

public boolean withdraw(double amount)
if(account.withdraw(amount))
dbConnection.dbBalanceUpdate(account.getAccount
No(), account.getBalance())
return true
return false
public void deposit(double amount)
account.deposit(amount)
dbConnection.dbBalanceUpdate(account.getAccountN
o(),account.getBalance())

40
The Account class

An Account class having
Instance variables
Balnce
Name
Account No
Constructor to set these variables
Withdraw and deposit methods
get methods
set methods are not wtitten yet

class Account
private String name
private String accountNo
private double balance
Account(String name,String accountNo, double
money)
this.namename
this.accountNoaccountNo
balancemoney

public void deposit( double amount )
balance amount
public boolean withdraw( double amount )
if (balance gt amount)
balance - amount
return true
return false

public String getAccountNo()
return accountNo
public String getAccountName()
return name
public double getBalance()
return balance
// end class Account

44
Connection Class - DBConnection

Methods
public boolean getPassword(String sifre)
If the sifre is found in the databses return true
public String getInfo(String variable)
After sifre is found - customer is found in the
databse
Get information and return to the control class
Variable can be miktar, Noo, soyad
public void dbBalanceUpdate(String
AccountNo,double balance)
When money is deposited or withdrawn update the
account in the database

45
The Frame class

Define
Define a state variable
, deposit, withdraw,
Panels
Buttons
No layout coordinates of components are given
Add compontets to panels
Adjust visibility of panels
Register components to listeners
Implements ActionListener as an inner class
actionPerformed method - actionEvent

Setcontrol method
Called from the atm control class
Sets the referance of the control object in Frame
class as frame object calls atm object very often
a referenc is needed

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Registering Action event