JAVA程序设计实验二.doc

JAVA程序设计实验报告姓 名刘创学 号132054137指导教师邢珍珍成 绩设备名称及软件环境Win8 JDK JRE环境实验名称类的继承与封装实验日期2016年一实验内容1. 类的继承与封装：定义抽象类Shape（形状）其中有抽象方法用来求某形状的周长和面积；定义Shape类的子类Circle（圆形）、Triangle（三角形）、Rect（矩形）其中包括该形状的位置、大小信息并实现求其周长和面积的方法。假设当前有圆心为（100,100）半径为60的圆，左上角坐标为（0,200），水平宽度为120，垂直高度为80的矩形，以及三个顶点坐标分别为（200,200）、（300，400）、（150,350）的三角形，请在控制台输出每个形状的相关信息，及所有形状的周长和面积的和。2.接口的定义与实现：通过接口和实现接口的类来完成上一题目。二重点及难点1. 熟练掌握类、类的数据成员和成员方法的定义与实现；2. 熟练掌握抽象类与类的继承的相关内容；3. 熟练掌握接口与接口的实现的相关内容；4. 熟练掌握public、private、static、final、abstract等修饰符的作用。三理论分析或算法分析首先构造一个二维顶点信息类Point2D方便以后的使用。其次构造一个shape抽象基类，分别被子类Circle（圆形）、Triangle（三角形）、Rect（矩形）所继承。在三角形面积计算中采取三对顶点构成的向量进行叉积取半，其中注意取绝对值，周长采用二维空间向量求其长度等，进而实现对任意形状的三角形计算其面积周长。最后再用接口技术实现以上功能。四实现方法（含实现思路、程序流程图和源程序列表等）1. 复习有关Java中类、类的继承、接口、接口的实现的相关内容；2. 根据题目要求编写需要的抽象类和其子类；3. 根据题目要求编写相应的main方法完成程序；4. 根据题目要求编写需要的接口和实现该接口的类；五实验结果分析（含执行结果验证、输出显示信息、图形、调试过程中所遇的问题及处理方法等）实验一：用继承实现实验二：使用接口实现的结果与上面结果相同以上的实验所涉及到的类有：部分代码展示1. public class Poin2D int x;int y;2. public abstract class Shape public abstract float Perimeter();public abstract float Area();3.public abstract class Circle extends Shape public int radius;public Circle(Poin2D p, int radius) super(p,radius,radius);public void PrintPos() public float Perimeter()public float Area() 4. public abstract class Triangle extends Shape public Triangle (Poin2D p1, Poin2D p2,Poin2D p3) super(p1, p2, p3);public void PrintPos() System.out.println(the pos of the Triangle P (X,Y)：P1：(+p1.x+ +p1.y+) P2:(+p2.x+ +p2.y+) P3:(+p3.x+ +p3.y+);public float Perimeter()Poin2D pp1 = new Poin2D();Poin2D pp2 = new Poin2D();Poin2D pp3 = new Poin2D();pp1.x = p2.x - p1.x;pp1.y = p2.y - p1.y;pp2.x = p3.x - p1.x;pp2.y = p3.y - p1.y;pp3.x = p3.x - p2.x;pp3.y = p3.y - p2.y;float edge1 = (float) (Math.sqrt(pp1.x * pp1.x + pp1.y * pp1.y) );float edge2 = (float) (Math.sqrt(pp2.x * pp2.x + pp2.y * pp2.y) );float edge3 = (float) (Math.sqrt(pp3.x * pp3.x + pp3.y * pp3.y) );float perimeter = edge1+edge2+edge3;return perimeter;public float Area()Poin2D pp1 = new Poin2D();Poin2D pp2 = new Poin2D();pp1.x = p2.x - p1.x;pp1.y = p2.y - p1.y;pp2.x = p3.x - p1.x;pp2.y = p3.y - p1.y;float area = (float)( Math.abs(pp1.x*pp2.y-pp1.y*pp2.x)/2;return area;5.public abstract class Rect extends Shape public Rect(Poin2D p, int width, int height) super(p, width, height);public void PrintPos() System.out.println(Pos: X:+pos.x+ Y:+pos.y);System.out.println(The width,height of the Rect is +width+, + height);public float Perimeter()float perimeter = (float) (2 * (width + height) );return perimeter;public float Area()float area = (float) width * height;return area;6.public class Test public static void main(Stringargs) / 圆的输出位置及周长面积计算System.out.println(Circle is calculating);int radius = 60;Poin2D p = new Poin2D();p.x = 100;p.y = 100;Circle circle = new Circle(p, radius) ;circle.PrintPos();System.out.println(the perimeter of the Circle is +circle.Perimeter();System.out.println(the area of the Circle is +circle.Area();/ 三角形三点位置以及周长面积计算System.out.println(Triangle is calculating);Poin2D p1 = new Poin2D();p1.x = 200;p1.y = 200;Poin2D p2 = new Poin2D();p2.x = 300;p2.y = 400;Poin2D p3 = new Poin2D();p3.x = 150;p3.y = 350;Triangle triangle = new Triangle(p1, p2, p3) ;triangle.PrintPos();System.out.println(the perimeter of the Triangle is +triangle.Perimeter();System.out.println(the area of the Triangle is +triangle.Area();/ 矩形的输出位置及周长面积计算System.out.println(Rect is calculating);p.x = 0;p.y = 200;int width = 120;int height = 80;Rect rect = new Rect(p,width,height) ;rect.PrintPos();System.out.println(the perimeter of the Rect is +rect.Perimeter();System.out.println(the area of the Rect is +rect.Area();/ 输出总面积和总周长System.out.println(All perimeter and area is calculating);float sumPerimeter = circle.Perimeter() + triangle.Perimeter() + rect.Perimeter();float sumArea = circle.Area() + triangle.Area()+ rect.Area();System.out.println(The perimeter of all is +sumPerimeter);System.out.println(The area of the all is +sumArea);7.接口实现部分代码 将shape定义为Interface 其他类进行impeletements实现接口即可 public interface IShape public abstract float Perimeter();public abstract float Area();public class Circle implement