Java Reference
In-Depth Information
public Finish getFinish() { return finish; }
}
Here, the relationships are as follows:
• The interface
Paintable
is a superinterface of class
PaintedPoint
.
• The interface
Colorable
is a superinterface of class
ColoredPoint
and of class
PaintedPoint
.
• The interface
Paintable
is a subinterface of the interface
Colorable
, and
Colorable
The class
PaintedPoint
has
Colorable
as a superinterface both because it is a superinter-
face of
ColoredPoint
and because it is a superinterface of
Paintable
.
Unless the class being declared is
abstract
, the declarations of all the method members of
each direct superinterface must be implemented either by a declaration in this class or by
an existing method declaration inherited from the direct superclass, because a class that is
It is permitted for a single method declaration in a class to implement methods of more than
one superinterface.
Example 8.1.5-3. Implementing Methods of a Superinterface
interface Colorable {
void setColor(int color);
int getColor();
}
class Point { int x, y; };
class ColoredPoint extends Point implements Colorable {
int color;
}
This program causes a compile-time error, because
ColoredPoint
is not an
abstract
class
but fails to provide an implementation of methods
setColor
and
getColor
of the interface
Colorable
.
In the following program:
interface Fish { int getNumberOfScales(); }
interface Piano { int getNumberOfScales(); }
class Tuna implements Fish, Piano {
