UML Weekend Crash Course™ - To Parent Directory

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Sunday Afternoon
As mentioned earlier, UML Class diagrams are comparable to XML schemas. Both define
the rules for how data is organized. The development team can use their modeling tool’s
XMI functionality to automatically generate an XML schema from the Class diagram, or they
can generate it by hand. I don’t show the XML schema here because reading XML schemas is
a large topic in and of itself. Instead, I show a sample XML document. The UML Object diagram
in Figure 29-9 is a valid instantiation of the Class diagram in Figure 29-8 and has the
same data and structure as this XML document.
:User
name="Victor Peters"
loginName="victorpeters"
password="sreteprotciv"
:Appointment
dateAndTime="1011384689352"
description="Meeting with business..."
priority="medium"
:Contact
name="Kermit T. Frog"
eMail="frog@kermit.com"
notes="Client wants pig detection system"
:Contact
name="Tom Pender"
eMail="tom@pender.com"
notes="Business Analyst and Designer"
Figure 29-9 UML Object diagram
The Object diagram in Figure 29-9 maps to the XML document in Listing 29-1. The User
object becomes the element. That element contains one sub-element for each
attribute of the user class. Each attribute, like , has the value of the attribute
followed by an end tag . The link from User to Appointment is shown as a
sub-element of the element and contains all the attributes in the Appointment
class. Notice that the dateAndTime (stored in Java milliseconds format) and priority are
attributes instead of being separate elements because they are simple values.
Listing 29-1
XML for the Appointments Object diagram
Victor Peters
victorpeters
sreteprotciv
Meeting with business analyst and client
Kermit T. Frog
frog@kermit.com
Client wants pig detection system