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7 Interfaces and volunteers

In this assignment you will modify the class diagram as follows:

  • A Volunteer class is added. A volunteer can also be hired, but at zero rate.
  • The Hire(int hours) method is only needed for Volunteer and Freelancer and is placed in an interface.

  • Persons are sorted using the IComparable interface.

    Mermaid diagram Mermaid diagram

  • If needed, retrieve the OOP Company project up to chapter 6 from DLO. It contains the classes as you left them at the end of chapter 6.

  • For the Person class:

    a) Add the IComparable<Person> interface (already done in 5 Abstract Person and polymorphism).
    b) The CompareTo() method sorts by the name of a person (already done).

  • Create an interface named IHireable in the Models folder with the method Hire(int hours). The code for the interface is: 

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    namespace Company.Models
{
    public interface IHireable
    {
        void Hire(int hours);
    }
}

  • Add the interface to the Freelancer class and override the Hire() method.

  • Add the Volunteer class to the Models folder according to the class diagram:

    a) The Hire() method does the same as in the Freelancer class.
    b) The CalculateYearlyIncome() method always returns 0.
    c) The ToString() method returns "name lives in city and works at department name at location and is a volunteer".

  • In the Main method of the launcher:

    a) Use the existing code and add the following four volunteers to the list:

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    people.Add(new Volunteer("Ambi", "Amsterdam", departments[0]));
people.Add(new Volunteer("Naledi", "Gaborone", departments[1]));
people.Add(new Volunteer("Ceren", "Istanbul", departments[2]));
people.Add(new Volunteer("Haining", "Shaoxing", departments[3]));

    b) Hire all volunteers for 160 hours.
    c) Sort the list alphabetically.
    d) Add code to get the following output (alphabetically sorted by name):

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    Ambi lives in Amsterdam and works at department Operations at Hilversum and is a volunteer
Ambi earns € 0,00 per year
Angelique lives in Rotterdam and works at department Management at Almere and is an employee with right to a bonus
Angelique earns € 65.000,00 per year
Anne lives in Zwolle and works at department Operations at Hilversum and is a freelancer with an hourly rate of 40
Anne earns € 12.800,00 per year
Caroline lives in Delft and works at department Support at Amsterdam and is an employee without right to a bonus
Caroline earns € 48.000,00 per year
Ceren lives in Istanbul and works at department Management at Almere and is a volunteer
Ceren earns € 0,00 per year
Haining lives in Shaoxing and works at department Documentation at Gouda and is a volunteer
Haining earns € 0,00 per year
Jannie lives in Utrecht and works at department Operations at Hilversum and is a freelancer with an hourly rate of 60
Jannie earns € 19.200,00 per year
Klaas lives in Diemen and works at department Documentation at Gouda and is a freelancer with an hourly rate of 50
Klaas earns € 16.000,00 per year
Mark lives in Den Haag and works at department Management at Almere and is an employee with right to a bonus
Mark earns € 130.000,00 per year
Naledi lives in Gaborone and works at department Support at Amsterdam and is a volunteer
Naledi earns € 0,00 per year
Ronald lives in Zaandam and works at department Operations at Hilversum and is a freelancer with an hourly rate of 80
Ronald earns € 25.600,00 per year