Computer scienceProgramming languagesJavaCode organizationObject-oriented programmingClass hierarchiesInterfaces and abstract classes

Fundamentals of interfaces in Java

Theory

Mutable geometric shapes

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Suppose, you are writing a geometric engine. Now it includes classes Circle, Rectangle and interfaces Movable and Scalable.

You need:

  1. to write a new interface MutableShape that extends both existing interfaces;

  2. to implement the new interface in each class;

  3. to override methods move and scale in both classes:

    • scale should multiply the radius of a circle by the specified factor;

    • scale should multiply width and height of a rectangle by the specified factor;

    • move should add dx and dy to the center of a circle;

    • move should add dx and dy to the upper-left corner of a rectangle.

See the provided code and read comments to understand your task better. The code is not compiled.

Note:

  • do not remove existing classes and their members (including getters and constructors).

  • do not make your classes and interfaces public

After your changes, the following code should be compiled:

MutableShape circle = new Circle(2.0f, 3.5f, 10.1f);

circle.move(10.1f, 20.2f);
circle.scale(2.2f);

((Circle) circle).getRadius();
Write a program in Java 17
interface Movable {
void move(float dx, float dy);
}

interface Scalable {
void scale(float factor);
}

final class Circle {

/**
* Defines the horizontal position of the center of the circle
*/
private float centerX;

/**
* Defines the vertical position of the center of the circle
*/
private float centerY;

/**
* Defines the radius of the circle
*/
private float radius;

public Circle(float centerX, float centerY, float radius) {
this.centerX = centerX;
this.centerY = centerY;
this.radius = radius;
}

public float getCenterX() {
return centerX;
}

public float getCenterY() {
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