第9次作业--接口及接口回调

一、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。

二、代码

1.Test.java

 

package c;
import java.util.Scanner;

import cc.Cone;
import cc.Factory;

public class Test {
    public static void main(String[] args) {
        while(true){
            Scanner reader = new Scanner(System.in);
            System.out.print("请输入你选择的形状:矩形r,三角形t,圆c,梯形T,正方形Z");
            char c = reader.next().charAt(0);
            Factory fa = new Factory();
            Cone cone = new Cone(fa.getShape(c), reader.nextDouble());
            System.out.print(cone.getVolume());
        }
    }
}

 

 2.Factory

 

package cc;
import java.util.*;
public class Factory {
    static Shape shape=null;
    public static Shape getShape(char c){
        switch(c){
        case 'z':System.out.println("请输入以正方形为底的柱体高:"); shape=new Zheng(15);break;
        case 't':System.out.println("请输入以三角形为底的柱体高:"); shape=new Triangle(3,3,3);break;
        case 'r':System.out.println("请输入以矩形为底的柱体高:"); shape=new Rectangle(7,8);break;
        case 'c':System.out.println("请输入以圆形为底的柱体高:"); shape=new yuan(120);break;
        case 'x':System.out.println("请输入以梯形为底的柱体高:"); shape=new tixing(7,8,9);break;
        }
        return shape;
    }

}

 

 3.Shape

package cc;
public interface Shape {
    double getArea();
}

 4.Cone

package cc;

public class Cone {
	Shape shape;
	double high;
	public Cone(Shape shape,double high){
	this.shape = shape;
	this.high = high;
}
public double getVolume(){
	return shape.getArea() * high;

}
public void setRect(Shape shape){
	this.shape = shape;
}
}

 5.Reactangle

package cc;

public class Rectangle implements Shape {
	double width;
	double length;
	

public Rectangle(double width,double length){
	this.length = length;
	this.width = width;
	
}
public double getArea(){
	return width * length;
}}

 6.yuan

package cc;
public class yuan implements Shape {
    double r;
    double PI=3.14;
    public yuan(double r){
        this.r=r;
    }
    public double getArea(){
        
        return PI*r*r;
    }
}

 7.Zheng

package cc;

public class Zheng extends Rectangle {
	public Zheng(double side){
		super(side,side);
	}
	public Zheng(){
		super(0,0);
	}
	public double getArea(){
		return width*length;
	}

}

 8.tixing

package cc;
public class tixing implements Shape {
    double a;
    double b;
    double height;
    public tixing(double a,double b,double height){
        this.a=a;
        this.b=b;
        this.height=height;
    }
    public double getArea(){
        return (a+b)*height/2;
    }
}

 9.triangle

package cc;

public class Triangle implements Shape {
    double a;
    double b;
    double c;
    public Triangle(double a,double b,double c){
        this.a=a;
        this.b=b;
        this.c=c;
    }
    public double getArea(){
        double p=(a+b+c)/2.0;
        return Math.sqrt(p*(p-a)*(p-b)*(p-c));
    }
}

 三、运行结果