33 ).
Though this violates the object-oriented encapsulation principle, this form can
be often observed in real-world systems. In Figure 4.33 , the GPS sender does not
communicate with the wrapper of the capsule (i.e., the truck, but directly with a
part??”the navigation system).
246 CHAPTER 4 SysML??”The Systems Modeling Language
A block can be explicitly modeled as a black box. In addition to the name of
a black-box block, we denote the keyword {encapsulated} (Abb. 4.29). In this
case, a connector must not be connected directly from the outside to a role in
the inside. The property is denoted by the verb {encapsulated} above the block ??™ s
name ( Figure 4.29 ).
Since interfaces are rather a software domain in the sense of UML, while blocks
are defi ned in more general terms, and considering that they can also represent
hardware elements, they are generally not used in combination with blocks.
However, interfaces are part of SysML. They are used to describe standard ports.
FIGURE 4-32
Nested blocks.
bdd [package] On-board computer [notation nesting]
?«block?»
On-board computer
card:Customer card
structure
structure card.
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