Wednesday, October 27, 2010

Accessors: Get

Classes may contain accessor behaviors for some or all of their states. This enables other objects to read the value of a state. An accessor behavior is nearly always implemented as a function, as a function returns a value to the calling procedure.

For example, the Player class now contains a number of accessor behaviors. Following convention, the names of these behaviors begin with the word Get.

In a class diagram, the format for a behavior that returns a value(function) looks like this:
Visibility FunctionName(ParametersIfAny):ReturnDataType

...as can be seen in the Player class example:
+GetName():String

The implementation (code) for an accessor, reads and returns the value of the state being accessed. In other words, the GetName() function will return a String (containing the value of the Name state) to the calling procedure.

An accessor behavior has visibility of Public.

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