main.java

抽象类的使用,定义一个TuXing抽象类,类中所有的方法都要求实现求面积的功能,一个要求求体积.

/*
 * Main.java
 *
 * Created on 2007年11月20日, 上午9:28
 *
 * To change this template, choose Tools | Template Manager
 * and open the template in the editor.
 */

package exp2;

/**
 *
 * @author Administrator
 */
public class Main{
  
    public static void main(String[] args) {
     
     changfangxing aa=new changfangxing(12,5);
     System.out.println("长方形的面积为:"+aa.Mianji());
     zhengfangxing bb=new zhengfangxing(10);
     System.out.println("正方形的面积为:"+bb.Mianji());
     zhengfangti cc=new zhengfangti(7);
     System.out.println("正方体的面积为:"+cc.Mianji());
     System.out.println("正方体的体积为:"+cc.Tiji());
    }
    
}

abstract class TuXing{
   abstract double Mianji();
   abstract double Tiji();
}

 class changfangxing extends TuXing{
   double Tiji(){
    return 0;}
     int longth,wide,area;
    changfangxing(int a,int b){
    longth=a;
    wide=b;
    }
    double Mianji(){
        area=longth*wide;
        return area;
     }
 }

 class zhengfangxing extends TuXing{
   double Tiji(){
   return 0;
   }
   int longth,area;
   zhengfangxing(int a){
   longth=a;
   }
    double Mianji(){
    area=longth*longth;
    return area;
    }
 }


class zhengfangti extends TuXing{
     int longth,area,t;
    zhengfangti(int a){
    longth=a;
    }
    double Tiji(){
    t=longth*longth*longth;
     return t;
    }
    double Mianji(){
     area=6*longth*longth;
     return area;
    }
}