Java design patterns

You have a CSV file that contains credit card records. Each record is on a line. It contains a field for the card number, the expiration date, and the name of the card holder. The fields are comma-separated. In your system you have the following class structure for the credit cards:

a class CreditCard,

classes VisaCC, MasterCC, AmExCC that are all subclasses of CreditCard,

you can assume more subclasses for other credit card types will be added later on.

You now have to design the method(s) (and maybe additional classes) that reads a record from the file, verifies that the credit card number is a possible account number, and creates an instance of the appropriate credit card class. What design patterns could you use for that?

Important details: Credit card numbers cannot exceed 19 digits, including a single check digit in the rightmost position. The exact algorithm for calculating the check digit is not important for this assignment. You can also determine the card issuer based on the credit card number:

MasterCard

First digit is a 5, second digit is in range 1 through 5 inclusive. Only valid length of number is 16 digits.

Visa

First digit is a 4. Length is either 13 or 16 digits.

AmericanExpress

First digit is a 3 and second digit a 4 or 7. Length is 15 digits.

Discover

First four digits are 6011. Length is 16 digits.





This is part 1



Continue with the design from Part 1 and extend it to parse different input file formats (json, xml, csv) and detect the type of credit card and then output to a file (in the same format as the input - json or xml or csv) - with each line showing the card number, type of card (if a valid card number) and an error (if the card number is not valid). The design should accommodate newer file formats for the future.

This is part 2



Implement an application (Java code and JUnit tests) for Part 1 and Part2 - that accepts input file name and output file name and writes an output file in the same format as the input (CSV or JSON or XML). Output should contain the details specified in Part 2.

Please consider updated JSON Input/Output files for the project.