4.5 Oral Final

Study the Class Diagram for the 4.4B IMoneyCollector and Chimpanzee design below. Be prepared to read and/or write code based on it. Be prepared to draw an Object Diagram based on the code written during the Oral Final.

Given the following class diagram and code, provide a refactored design, without using inheritance. Show the processing of all possessions in a single loop without any conditionals based on type.

• NNew
• CChanged
• RRemoved

public void SortPossessions()
{
foreach (Magazine m in this.magazines)
{
if (m.DateLastRead < DateTime.Today)
{
this.Trash(m);
}
}
foreach (CD cd in this.cds)
{
if (cd.DateLastListened < DateTime.Today)
{
this.Trash(cd);
}
}
}

Create a class diagram and write code or pseudo-code of the refactored loop.

Refer to Module 4.4.

You are developing your own text editor for editing any text file. Your current design, shown in the class diagram below, requires a text editor class to use TxtDocument class, which represents a document with the .txt file extension. You soon realize that your design is not extensible when you want to be able to edit XML and XAML documents in your text editor.

• NNew
• CChanged
• RRemoved

Create a class diagram of an alternative design that implements the dependency inversion principle so that your text editor can edit .txt, .xml, and .xaml documents.

Refer to the Module 4.4 Readings on the dependency inversion principle.

A customer class is used in a WPF application. The following code sets the customer's phone number if the value matches the regex pattern. Otherwise, it notifies the user via a message box that the phone number is not valid.

public string Phone
{
get
{
return this.phone;
}
set
{
if (!Regex.IsMatch(value, @"((\(\d{3}\) ?)|(\d{3}-))?\d{3}-\d{4}"))
{
MessageBox.Show("Phone number is invalid. Ex: 715-555-1234");
}
else
{
this.phone = value;
}
}
}

You are given a requirement that the customer class be used in both a WPF application and a console application, which wouldn't be able to use a message box. Refactor the setter of the Phone property to allow the customer class to be used by two different user interfaces in a way that still validates the phone number. Be prepared to explain how the user interface would use the validation provided by the customer class.

Refer to the Module 4.2 readings.