第9次作业--接口及接口回调

1、题目：

       利用接口和接口回调，实现简单工厂模式，当输入不同的字符，代表相应图形时，利用工厂类获得图形对象，再计算以该图形为底的柱体体积。

2、源代码

Test.java

import java.util.Scanner;

/*主方法接受字母输出结果
*/
public class Test {

    @SuppressWarnings("resource")
    public static void main(String[] args) {
        // TODO Auto-generated method stub

        System.out.println("请输入底面形状的字母：");
        while (true) {
            @SuppressWarnings("resource")
            Scanner reader = new Scanner(System.in);
            char c = reader.next().charAt(0);
            if (c == 'e') {
                System.out.println("退出");
                return;
            } else {
                Factory f = new Factory();
                Cone cone = new Cone(f.getShape(c), 4);
                System.out.println(cone.getV());
            }
        }

    }

}

 

Factory.java

/*Factory简单工厂方法
 * getShape方法
 * switch选择
*/
public class Factory {
    Shape shape=null;
       Shape getShape(char c){
           switch(c){
           case't':shape=new TiXing(6,8,8);break;
           case'j':shape=new JuXing(5,5);break;
           case'z':shape=new ZhengFang(5);break;
           case'y':shape=new Yuan(9);break;
           case's':shape=new SanJiao(4,5,5);break;
           default:System.out.println("error");  
           }
           return shape;
       }

}

Shape.java

/*定义Shape接口
*/
public interface Shape {
    public double getArea();

}

Cone.java

/*Cone类
 *getV方法
*/
public class Cone {
    Shape shape;
    double high;

    public Cone(Shape shape, double high) {
        this.shape = shape;
        this.high = high;
    }

    public double getV() {
        return shape.getArea() * high;
    }
}

JuXing.java

/*定义JuXing类使用Shape接口
 * JuXing构造方法
 * getArea方法
*/
public class JuXing implements Shape {
    double width;
    double length;

    public JuXing(double width, double length) {
        this.width = width;
        this.length = length;
    }

    public double getArea() {
        return width * length;
    }

}

SanJiao.java

/*定义SanJiao类使用Shape接口
 * SanJiao构造方法
 * getArea方法
*/
public class SanJiao implements Shape {
    double a;
    double b;
    double c;

    public SanJiao(double a, double b, double c) {
        this.a = a;
        this.b = b;
        this.c = c;
    }

    public double getArea() {
        double p = (a + b + c) / 2;
        return Math.sqrt(p * (p - a) * (p - b) * (p - c));
    }

}

TiXing.java

/*定义TiXing类使用Shape接口
 * TiXing构造方法
 * getArea方法
*/
public class TiXing implements Shape {
    double a;
    double b;
    double h;

    public TiXing(double a, double b, double h) {
        this.a = a;
        this.b = b;
        this.h = h;
    }

    public double getArea() {
        return (a + b) * h / 2;
    }

}

Yuan.java

/*定义Yuan类使用Shape接口
 * Yuan构造方法
 * getArea方法
*/
public class Yuan implements Shape {
    double r;

    public Yuan(double r) {
        this.r = r;
    }

    public double getArea() {
        double area = Math.PI * r * r;
        return area;
    }

}

ZhengFang.java

/*定义ZhengFang类继承JuXIng
 * ZhengFang构造方法
 * getArea方法
*/
public class ZhengFang extends JuXing {
    public ZhengFang() {
        super(0, 0);
    }
    
    public ZhengFang(double side) {
        super(side, side);
    }

    public double getArea() {
        return width * width;
    }
}

3.运行结果