Copyright 2014 John Bono Phd All Rights Reserved 1lab 3 Goal

Copyright 2014 John Bono Phd All Rights Reserved1lab 3 Goal

The purpose of this lab is to demonstrate an understanding of static variables and methods. You are working for Plastercard, Inc., a company that specializes in credit cards for handymen. The company plans to launch a new credit card and needs your help in designing an object-oriented application to run usage of the credit card. Based on some requirements analysis, you create the following detailed UML diagram for a CreditCard class: (+) DEFAULT_CREDIT_LIMIT: double The default credit limit across all credit cards ($1000.00) (-) numOpenAccounts: int The number of open credit card accounts (-) lastAccountNumber: int Starting at 200, the last account number assigned (-) accountNumber: int The account number of the credit card (-) numCyclePurchases: int The number of purchases made in a billing cycle of the credit card (-) balance: double The balance of the credit card (-) creditLimit: double The credit limit of the credit card (-) open: boolean The status of the credit card (open or closed) (+) CreditCard() Constructs a default CreditCard object with an account number, number of purchases made in a billing cycle, balance, credit limit, and open status (+) CreditCard(creditLimit : double) Constructs a CreditCard object with a specified credit limit (+) getAccountNumber(): int Returns the account number of this credit card (+) getNumCyclePurchases(): int Returns the number of purchases made in a billing cycle of this credit card (+) getBalance(): String Returns the balance of this credit card (+) getCreditLimit() : double Returns the credit limit of this credit card (+) isOpen(): boolean Returns the status of this credit card (open or closed) (+) getNumOpenAccounts(): int Returns the number of open credit card accounts (+) charge(amount : double): boolean Returns if a credit card charge was successful if the account was open, a valid amount was provided, and the balance would not exceed the credit limit. The amount is added to the balance and the number of purchases made in the billing cycle is incremented (+) payBill(amount : double): boolean Returns if the credit card bill was successfully paid if the account was open and the amount to pay equaled the amount 2 of the balance. The balance and number of purchases made in the billing cycle is reset to 0 (+) close(): boolean Returns if the credit card was successfully closed only If the credit card was open (+) toString(): String Returns a string representation of this Credit Card. Create a data definition class based on this UML diagram, then an implementation class to test its methods with hardcoded data.

Paper For Above instruction

The development of an effective credit card system for Plastercard, Inc., which specializes in credit cards for handymen, necessitates a thorough understanding of object-oriented programming principles—particularly static variables and methods. In designing the system, the UML diagram provided serves as a blueprint for creating a comprehensive CreditCard class that encapsulates all relevant attributes and behaviors essential for managing credit card accounts efficiently.

The core class, CreditCard, maintains both individual instance variables and class-wide static variables. Static variables such as DEFAULT_CREDIT_LIMIT, which defaults to $1000.00, and lastAccountNumber, initialized at 200, are shared among all instances and are instrumental for maintaining consistent baseline values and sequential account numbering. Conversely, instance variables like accountNumber, balance, creditLimit, open, numCyclePurchases, and other attributes store specific data pertinent to each user's credit card.

Implementing static methods is crucial for utility functions that pertain to class-wide data, such as retrieving the number of open accounts through getNumOpenAccounts(). This method, being static, can be invoked without instantiating an object, thus enabling quick access to class-level data. Such design choices optimize resource management and provide a clear structure aligning with object-oriented best practices.

The class constructor methods, both default and parameterized, initialize objects with default or specified credit limits, assigning unique account numbers incrementally for each new account. The security of transactions is maintained through methods like charge(), which adds an amount to the balance only if the account is open, the amount is valid, and the credit limit is not exceeded. Additionally, the payBill() method allows for partial or full payments, resetting the balance and purchase count upon successful transactions, aligning with real-world principles of credit management.

The close() method facilitates closing an open credit card, preventing further transactions, which is vital for real-world credit lifecycle management. The toString() method provides a user-friendly string representation of each object’s state, which is essential for debugging and user interface display.

Testing these functionalities involves creating instances with hardcoded values, as exemplified through a main program running scenarios such as valid charges, bill payments, and account closures. The implementation class ensures that all methods work correctly and that the static variables correctly track the overall state of the system, such as total number of open accounts.

In conclusion, leveraging static variables and methods in the design of this credit card system offers efficiency and clarity. It facilitates data sharing across instances while maintaining individual account integrity, essential for scalable and maintainable financial software applications.

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