Composition And Class Interfaces Abstract Class Lab Steps ✓ Solved

Composition And Class Interfacesabstract Classlab Stepsstep 1 Unders

Understand the UML Diagram

The only change to the Employee class is that there is a new attribute: +benefit : Benefit Notice that there is a "+" for this attribute, meaning that it is public. Make sure to examine the multi-arg constructor's signature! Also, the dotted directed line between Employee and iEmployee specifies that the Employee class must implement the iEmployee abstract class, and thus provide an implementation for the calculatePay method.

Create the Project

You will want to use the Week 3 project as the starting point for the lab. To do this, you will want to create a new project by following these steps: 1. Create a new project and name it "CIS247C_WK4_Lab_LASTNAME". 2. Copy all the source files from the Week 3 project into the Week 4 project. 3. Before you move on to the next step, build and execute the Week 4 project.

Modify the Employee Class

1. Using the UML Diagrams from Step 1, create the Benefit class. To get an idea of how to format displayBenefits, take a look at the output in Step 5. 2. Add a Benefit attribute to the Employee class. 3. Initialize the new Benefit attribute in both Employee constructors. Again, take note of the multi-arg constructors parameter list! 4. Create the iEmployee interface (abstract class in C++). 5. Modify the Employee class to implement the new interface so that Employee will have to implement the calculatePay method. 6. Modify the Employee class to call displayBenefit when displaying Employee information.

Modify the Main Method

Notice that the Employee class now has a public benefit object inside it. This means that you can access the set methods of the Benefit object with the following code: <Employee object>.benefit.<method> As an example, to set the lifeInsurance attribute inside an Employee object called emp, we could execute the following code: emp.benefit.setLifeInsurance(lifeInsurance);

The steps required to modify the Main class are below. New steps are in bold. 1. Create an Employee object using the default constructor. 2. Prompt for and then set the first name, last name, and gender. Consider using your getInput method from Week 1 to obtain data from the user for this step as well as Step 3. 3. Prompt for and then set the dependents and annual salary using the overloaded setters that accept Strings. 4. Prompt for and set healthInsurance, lifeInsurance, and vacation. 5. Using your code from Week 1, display a divider that contains the string "Employee Information". 6. Display the Employee Information. 7. Display the number of employees created using getNumEmployees(). Remember to access getNumEmployees using the class name, not the Employee object. 8. Create a Benefit object called benefit1 using the multi-arg construction. Use any information you want for health insurance, life insurance, and vacation. 9. Create another Employee object and use the constructor to fill it with the following: "Mary", "Noia", 'F', 5, 24000.0, benefit. Using your code from Week 1, display a divider that contains the string "Employee Information". 11. Display the employee information. 12. Display the number of employees created using getNumEmployees(). Remember to access getNumEmployees using the class name, not the Employee object.

Compile and Test

When done, compile and run your code. Then, debug any errors until your code is error-free. Check your output to ensure that you have the desired output, modify your code as necessary, and rebuild.

Screen Prints

Capture the Console output window and paste it into a Word document. The following is a sample screen print.

Submit Deliverables · Capture the Console output window and paste it into a Word document. · Upload the zip file and screenshots (Word document that contains programming code and screenshots of program output).

Sample Paper For Above instruction

Introduction

The integration of composition and class interfaces, especially through abstract classes, is a fundamental aspect of object-oriented programming (OOP). This paper explores the process of implementing a Benefit class within an existing Employee structure, leveraging UML diagrams, interface creation, and class modification to enhance functionality. It discusses the practical steps involved, including project setup, class editing, interface implementation, and testing, to demonstrate how these principles facilitate modular, maintainable, and scalable code development.

Understanding the UML Diagram and Initial Setup

The UML diagram serves as a blueprint that guides the enhancement of the Employee class. The primary modification involves adding a new attribute, +benefit : Benefit, indicating that each Employee will now have an associated Benefit object. The diagram also indicates that Employee must implement the iEmployee interface or abstract class, which mandates the implementation of the calculatePay method. This step ensures adherence to a consistent contract for Employee subclasses, promoting polymorphism and interface-driven design.

Creating the project based on the previous week's work provides a practical foundation. By copying source files from Week 3 into a new project and then building and executing the code, developers ensure operational continuity while enabling modifications necessary for the lab. This approach underscores the importance of version control and incremental development in software projects.

Class Modifications and Implementation

The core of the task involves creating a Benefit class, which encapsulates employee benefits such as health insurance, life insurance, and vacation days. This class must be well-formatted, with displayBenefits() for output purposes. Subsequently, the Employee class is extended to include a public Benefit attribute, initialized in all constructors to ensure consistency.

Implementing the iEmployee interface in Employee requires defining the calculatePay() method, a critical function that calculates employee compensation based on various attributes. The Employee class is also modified to call displayBenefit() when presenting employee information, ensuring benefits are visible details within reports.

Modifications to the Main Method

The Main class facilitates user interaction, guided by prompts that gather employee data, including personal information and benefits. Accessing the nested Benefit object via emp.benefit allows for setting specific benefit attributes, exemplified by setting life insurance. Creating Employee instances with different constructors demonstrates the flexibility of initializations, and displaying the number of employees emphasizes resource tracking.

Testing and Output Validation

After implementing changes, compilation and testing are vital. Debugging ensures error-free execution, and output validation confirms the correct display of employee details, including benefits and calculated pay. Capturing console output for documentation provides transparency and verification of functionality, essential for academic and professional submissions.

Conclusion

Incorporating composition through Benefit objects and implementing interfaces in Employee classes exemplifies solid OOP practices that promote code reuse, scalability, and clarity. The systematic approach of project setup, class development, user interaction, and testing demonstrates an effective methodology for managing complex codebases. This process not only enriches understanding of UML-based design but also exemplifies best practices in Java/C++ programming.

References

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