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A-Kind-Of relationship
Comparison of Point and Circle
class Point {
attributes:
int x, y
methods:
setX(int newX)
getX()
setY(int newY)
getY()
}
class Circle {
attributes:
int x, y, radius
methods:
setX(int newX)
getX()
setY(int newY)
getY()
setRadius(newRadius)
getRadius()
}
Conclusion: Knowing the properties of class Point we can describe a circle as a point plus a radius and methods to access it.
A-Kind-Of

| Comparing both class definitions we can observe the following:
| •Both classes have two data elements x and y. In the class Point these elements describe the position of the point, in the case of class Circle they describe the circle's center. Thus, x and y have the same meaning in both classes: They describe the position of their associated object by defining a point.
| •Both classes offer the same set of methods to get and set the value of the two data elements x and y.
| •Class Circle ``adds'' a new data element radius and corresponding access methods.