JAVA面向对象程序设计上机实践.doc

JAVA面向对象程序设计上机实践1.定义一个接口，接口中有四个抽象方法：求面积方法、求周长方法、显示面积方法及显示周长方法。定义Circle类和Rectangle类分别实现接口，在主类中实现显示圆和矩形的面积和周长。2.重写上面的程序，要求矩形，圆的类放到不同的包中，用包的技术组织程序的设计。同时要求程序能从键盘上接受数据以便求解不同的几何图形的周长面积。1.public interface J_Shape public abstract double mb_getArea();public abstract double mb_getPerimeter();public class J_Circle implements J_Shape public double m_radius;public J_Circle(double r)m_radius=r;public double mb_getArea()return(Math.PI*m_radius*m_radius);public double mb_getPerimeter()return(Math.PI*2*m_radius);public static void main(String args)J_Shape a=new J_Circle(5);System.out.println(the area of circle is: + a.mb_getArea();System.out.println(the perimeter of circle is + a.mb_getPerimeter();public class Rectangle implements J_Shape public double longs,wides;public Rectangle(double l,double w)longs=l;wides=w;public double mb_getArea() return(longs*wides);public double mb_getPerimeter() return (2*(longs+wides);public static void main(String args)J_Shape a=new Rectangle(2,3);System.out.println(the area of rectangle is:+a.mb_getArea();System.out.println(the perimeter of rectangle is:+a.mb_getPerimeter();2.public interface J_Shape public abstract double mb_getArea();public abstract double mb_getPerimeter();import java.io.BufferedReader;import java.io.IOException;import java.io.InputStreamReader;public class J_Square implements J_Shape public double radious;public J_Square(double x)radious=x;public double mb_getArea() return(Math.PI*radious*radious);public double mb_getPerimeter() return (Math.PI*radious*2);public static void main(String args)throws IOExceptionBufferedReader input=new BufferedReader(new InputStreamReader(System.in);System.out.print(Enter one number:);int number=Integer.parseInt(input.readLine();J_Shape a=new J_Square(number);System.out.println(the area of circle is:+a.mb_getArea();System.out.println(the perimeter of circle is:+a.mb_getPerimeter();import java.io.BufferedReader;import java.io.IOException;import java.io.InputStreamReader;public class Rectangle implements J_Shape public double longs,wides;public Rectangle(double l,double w)longs=l;wides=w;public double mb_getArea() return(longs*wides);public double mb_getPerimeter() return (2*(longs+wides);public static void main(String args)throws IOExceptionBufferedReader input=new BufferedReader(new InputStreamReader(System.in);System.out.print(Enter one number1:);int number1=Integer.parseInt(input.readLine();System.out.print(Enter one number2:);int number2=Integer.parseInt(input.readLine();J_Shape a=new Rectangle(number1,number2