Java-Interface Exercise 1

1. (1) write an interface Shapepara: The method in the interface: int Getarea (): Gets the area of the graph. int getcircumference (): Get the perimeter of the graph

(2) Write a circle-like circle, which requires that the Circle class circle implement the interface Shapepara.

The class contains a member variable:

Radius:public the decorated double type radius, which represents the radius of the circle.

x : The private decorated double variable x, which represents the horizontal axis of the center.

y : Protected modified double variable y, which represents the ordinate of the center point.

The methods that are included are:

Circle (double radius) a method for constructing a parameter. Initializes the radius with the parameters in the formal parameter list, and the center point is the coordinate origin. Double Getradius (): Gets the return value of the radius to the method. void SetCenter (double x, double y): Sets the center coordinate of the class circle using the parameters in the formal parameter list. void Setradius (double radius): Sets the radius domain of the class circle using the parameters in the formal parameter list.

Interface:

 Package Com.lianxi6;  Public Interface Shapepara {            // constant    double pi=3.14;         // abstract Methods    Double Getarea ();         Double getcircumference ();        }

 PackageCom.lianxi6; Public classCircleImplementsShapepara {//Properties    Private Doublex; Private Doubley; Private Doubleradius;  Public DoubleGetX () {returnx; }     Public voidSetchenter (DoubleXDoubley) { This. x =x;  This. y =y; }     Public DoubleGetY () {returny; }     Public DoubleGetradius () {returnradius; }     Public voidSetradius (Doubleradius) {         This. Radius =radius; }        //Construction Method     PublicCircle (Doubleradius) {        Super();  This. x = 0;  This. y = 0;  This. Radius =radius; } @Override Public DoubleGetarea () {returnPi*math.pow (RADIUS, 2); } @Override Public Doublegetcircumference () {return2*pi*radius; }}

 Package Com.lianxi6;  Public class Test {    publicstaticvoid  main (string[] args) {        Circle c=  New Circle (ten);        C.setchenter (3, 4);        System.out.println (C.getarea ());            }      Public void Han (Shapepara s)    {        s.getarea ();    }}

Results:

Java-Interface Exercise 1