## FinalProject.pdf

Final Project – Credit card numbers and the case of Mobius Duck

In this project, you are assisting an investigation. The investigator asked you to help him determine the

validity of credit card numbers located in a case of Mobius Duck, case number 20150510-001.

Your task is to:

– Read the data listed below “Data to Evaluate” from a file.

– Evaluate each number to see if they are representing a possible credit card number.

– Validate each credit card number to see if they are a valid number.

– Store the valid numbers and invalid numbers in a separate array.

– Write the contents of validated credit card number array into a file called “valid_cards.txt”.

– Write the invalid credit card number array to a file called “invalid_numbers.txt”.

– Make sure to include the issuer for each group of credit card numbers identified.

– Your application should work with any number of credit card entries.

Turn in:

– Source code ( .java ) files of all classes and driver class.

– Completed UML for application classes.

– Flow chart for every method that contains beyond sequential logic flow.

– Generated javadocs structure.

– Input and output files

Grading:

– Naming standard followed for project files – 2%

– Input and output files – 2%

– Javadoc structure – 5%

– Project compiled without error – 91%

– Proper use of internal comments, docstrings, and tags – 5%

– Self documenting field, identifier, method, static, final, and class identifiers – 5%

– Properly validated input and output files – 5%

– Properly used arrays to store data – 5%

– Correct output calculated by the Luhn algorithm and card number issuer identified – 71%

Extra Credit:

– Implement the full Issuer IIN Range instead of the simplified list.

How to validate Credit Card Numbers?

Most credit card number can be validated using the Luhn algorithm, which is more or a less a glorified Modulo

10 formula!

The Luhn Formula:

• Drop the last digit from the number. The last digit is what we want to check against

• Reverse the numbers

• Multiply the digits in odd positions (1, 3, 5, etc.) by 2 and subtract 9 to all any result higher than 9

• Add all the numbers together

• The check digit (the last number of the card) is the amount that you would need to add to get a multiple

of 10 (Modulo 10)

Luhn Example:

Steps Total

Original Number: 4 5 5 6 7 3 7 5 8 6 8 9 9 8 5 5

Drop the last digit: 4 5 5 6 7 3 7 5 8 6 8 9 9 8 5

Reverse the digits: 5 8 9 9 8 6 8 5 7 3 7 6 5 5 4

Multiple odd digits by 2: 10 8 18 9 16 6 16 5 14 3 14 6 10 5 8

Add digits from line above 1 8 9 9 7 6 7 5 5 3 5 6 1 5 8

Add all numbers: 1 8 9 9 7 6 7 5 5 3 5 6 1 5 8 85

Mod 10: (85 + X) modulo 10 = 0 , thus X=5 (last digit of card)

List of credit card number formats

Credit Card Issuer Starts With ( IIN Range ) Length ( Number of digits )

American Express 34, 37 15

Diners Club – Carte Blanche 300, 301, 302, 303, 304, 305 14

Diners Club – International 36 14

Diners Club – USA & Canada 54 16

Discover

6011, 622126 to 622925, 644, 645, 646,

647, 648, 649, 65

16

InstaPayment 637, 638, 639 16

JCB 3528 to 3589 16

Laser 6304, 6706, 6771, 6709 16-19

Maestro

5018, 5020, 5038, 5893, 6304, 6759, 6761,

6762, 6763

16-19

MasterCard 51, 52, 53, 54, 55 16-19

Visa 4 13-16

Visa Electron 4026, 417500, 4508, 4844, 4913, 4917 16

Data to Evaluate

3158539628375348

3337465828248404

3112804683572030

3112804683572033

5435528978467581

6706465468107999

6304362971054667

6706169762827894

6706169762827892

4844104341377697

4913405490886727

4844885754351829

4844885754351822

6371473570875275

6381475006869978

6389057917814806

347100734345549

347100734345543

6011162533805000

6011621663574413

6011824617460743

6011824617460745

6389057917814802

4539318768050385

36880982786892

36845793345501

36661154562232

36661154562234

5893329089846994

6761680165952016

6763100400984029

6763100400984022

5127043299122389

5330838017737340

5429168755154025

5429168755154023

375354034606481

379570632133224

4485521241443135

4532916206508075

4532916206508076

5590976687287124

5540641137519895

5540641137519892

30522070708059

30066552673241

30365487186802

30365487186801

Simplified Issuer Codes for Final Project:

VISA:

45

44

MasterCard:

51

53

American Express (AMEX):

37

34

Discover:

60

JCB:

31

33

Diners Club – North America:

54

55

Diners Club – Carte Blanche:

30

Diners Club – International:

36

Maestro:

58

LASER:

67

Visa Electron:

48

49

InstaPayment:

63

- Final Project – Credit card numbers and the case of Mobius Duck
- How to validate Credit Card Numbers?
- The Luhn Formula:
- Luhn Example:
- List of credit card number formats
- Simplified Issuer Codes for Final Project: