Question

JAVA编程题：编一个程序包含一个接口 shape（该接口中定义抽象函数calarea()）, 一个圆类和一个长方形类

编写一个程序，包含一个接口 shape（该接口中定义抽象函数calarea()）, 一个圆类和一个长方形类，分别实现接口shape(即需实现其中的calarea() 函数) ，定义一个test类，在其中创建圆对象和长方形对象，分别计算二者的面积。

Answer 1

//Shape.java
public interface Shape{
public double calarea();
}
//Rectangle.java
public class Rectangle implements Shape{
private double length;
private double high;
public Rectangle(double length,double high){
this.length = length;
this.high = high;
}
public double calarea(){
return length*high;
}
}

//Circle Circle.java
public class Circle implements Shape{

private double radius;
public double calarea(){
return Math.PI*radius*radius;
}
public Circle(double radius){
this.radius = radius;
}
}
//Test.java
public class Test{
public static void main(String []args){
Shape recShape = new Rectangle(2.7,4.8);
Shape cirShape = new Circle(5.0);
System.out.println(recShape.calarea());
System.out.println(cirShape.calarea());
}
}
直接手写的，辛苦吧