Credit Card Processing System

Getting Started

This project implements a credit card processing system in Java, capable of reading credit card records from different file formats (CSV, JSON, XML), validating them, and identifying the card issuer.

Folder Structure

• The project's Java files are located at the root directory.
• lib: the folder to maintain dependencies.
• .vscode/settings.json: contains project settings including referenced libraries.
• Test: the folder contains the unit test for every java class of the project.
• uml: contains the class diagram of all the design patterns used in the project.
• Compiled output files are generated in the root folder by default.

Project Configuration

The project is configured in .vscode/settings.json to reference libraries stored in the lib folder:

How to Run

Make sure you are in the project root directory.

1. Compile the Project:

• javac -cp ".;lib/*" *.java

2. Run the Application: The main method is in the CreditCardProcessor class.

• For CSV files:

    java -cp ".;lib/*" CreditCardProcessor input_file.csv output_file.csv  
  

• For JSON files:

  java -cp ".;lib/*" CreditCardProcessor input_file.json output_file.json
  

• For XML files:

  java -cp ".;lib/*" CreditCardProcessor input_file.xml output_file.xml
  

Primary Problem

The system addresses the challenge of parsing and processing credit card records from various file formats, validating card numbers, and determining the card issuer.

Secondary Problems

• File Format Flexibility: Ability to handle multiple file formats (CSV, JSON, XML) and extend to new ones.
• Credit Card Validation: Validation of credit card numbers and identification of card issuers like Visa, MasterCard, AmericanExpress, and Discover.

Design Patterns Used

• Factory Pattern: In CreditCardFactory, creates instances of different credit card types based on card numbers.
• Strategy Pattern: Through Strategy interface with implementations like CSVStrategy, JSONStrategy, and XMLStrategy, for flexible file parsing.

UML Class Diagram for Factory Pattern Implementation:

UML Class Diagram for Strategy Pattern Implementation:

Consequences of Using These Patterns

• Factory Pattern: Pros: Simplifies object creation and centralizes logic. Cons: The factory class may require modifications for new card types.

• Strategy Pattern: Pros: Enhances flexibility and scalability for file parsing. Cons: Can introduce complexity with multiple strategy classes.

Dependency Management

Dependencies are managed manually. Ensure that all required libraries are included in the lib folder.