Exercise: software list

Sometimes it takes more than just a glance at the class diagram to spot problems with a design. Consider the following class type that might be used by a software vendor to list software titles that are available.

Software class diagram

• There is nothing obviously wrong with this design. However, the users of this database might enter data that would cause problems, as shown in this table:

WordyMacrosoftWin, Mac9.4, 6.7
Visual B--MacrosoftWin6.0
CherokeeOpen SourceLinux, Solaris10.4.5.2,
InlookHinkysoftWin, Linux, Palm OS0.5
Corral DrawCorralMac22.1

• Revise the class diagram to correct any problems that you find in this design. Then draw the relation scheme for your corrected model.