Sybase Powerdesigner 7.5, Руководство пользователя

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Defining interfaces
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Defining interfaces
An interface is a type of class that is similar to a class but which is used to
implement the specification of an abstraction of a class. An interface is a
collection of operations used to specify the externally visible behavior of a
class. It has no implementation of its own.
A class that implements all the operations in an interface is said to realize the
interface. A class that requires one or more operations in an interface is said
to use the interface. The interface includes the signatures of the operations of
the class. Usually, an interface specifies only a limited part of the behavior of
a class. A class can implement one or more interfaces.
The following example shows a Name (interface) that realizes the action
GetName for an Employee (class).
Interface properties
An interface has the following properties:
Property Description
Maximum
length
Name Name of the interface 254
Code Reference name for the interface 254
Comment Descriptive comment for the interface —
Stereotype Subclassification of an interface derived from an
existing one. Extends the semantics of an interface
without changing it's structure —
Visibility Visibility of the interface, whose value denotes
how it may be seen outside its enclosing name
space —
Generate Indicates that the class will be automatically
included among the objects generated from the
model when you launch the generation process —