全国2011年1月Java语言程序设计自考试题

河北工业大学计算机学院网络编程实验报告

System.out.println(\saler 325 saled 10 goods at price 124.8;\ sale.SaleCount(10,124.8);

System.out.println(\saler 108 saled 45 goods at price 123.4;\ sale.SaleCount(45,123.4);

System.out.println(\saler 901 saled 100 goods at price 121.5;\ sale.SaleCount(100,121.5); sale.display(); } } 结果：

（3）定义接口Shape及其抽象方法getArea()和getPerimeter()用于计算图形和面积和周长。定义类Rectangle(矩形)、类Circle(圆形)、类Triangle(三角形)，要求这些类继承点类Coordinates()并实现接口的抽象方法。 代码： class Test {

public static void main(String args[]) { }

circle c=new circle(); c.display();

rectangle r=new rectangle(); r.display();

triangle t=new triangle(); t.display();

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河北工业大学计算机学院网络编程实验报告

}

interface cal_Shape { }

class Coordinates implements cal_Shape {

final double PI=3.14;

abstract double getArea(double r);

abstract double getArea(double a,double b);

abstract double getArea(double a,double b,double c); abstract double getPerimeter(double r);

abstract double getPerimeter(double a,double b);

abstract double getPerimeter(double a,double b,double c);

public double getArea(double r) { }

public double getPerimeter(double r) { }

public double getArea(double a,double b) { }

public double getPerimeter(double a,double b) { }

public double getArea(double a,double b,double c) { }

double s=(a+b+c)/2;

return Math.sqrt(s*(s-a)*(s-b)*(s-c)); return 2*(a+b); return a*b; return 2*PI*r; return PI*r*r;

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河北工业大学计算机学院网络编程实验报告

}

public double getPerimeter(double a,double b,double c) { }

return a+b+c;

class circle extends Coordinates {

public void display() {

double circle_area,circle_perimeter; Coordinates x=new Coordinates(); circle_area=x.getArea(2.0);

circle_perimeter=x.getPerimeter(2.0);

System.out.println(\半径为2的圆的面积为：\周长为：\ }

class rectangle extends Coordinates {

public void display() {

double rectangle_area,rectangle_perimeter;

Coordinates y=new Coordinates(); rectangle_area=y.getArea(2.0,3.0);

rectangle_perimeter=y.getPerimeter(2.0,3.0); }

System.out.println(\长,宽为2,3的矩形的面积为：\周长为：\

}}

class triangle extends Coordinates {

{

public void display()

double triangle_area,triangle_perimeter;

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河北工业大学计算机学院网络编程实验报告

Coordinates z=new Coordinates(); triangle_area=z.getArea(3.0,4.0,5.0);

triangle_perimeter=z.getPerimeter(3.0,4.0,5.0);

System.out.println(\三边长为3,4,5的三角形的面积为：\周长为：\ } 结果：

}

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