图形类作业

作业

题一

Graph.java

package com.maps.one;
/**
 * 
　 * 
Title: Graph.java
 
　 * 
Description:抽象类的使用 
 
　 * @author PoleYupro 
　 * @date 2019年9月27日
 */
public abstract class Graph implements Comparable {
     
	/*
	 * 定义两个抽象方法
	 */
	public abstract double area();
	public abstract double girth();
	
	public int compareTo(Graph graph){
     
		int i = 0;
		if(this.area()>graph.area()){
     
			return i=1;
		}else if(this.area()<graph.area()){
     
			return i=-1;
		}else{
     
			return i=0;
		}
	}
}

Circle.java

package com.maps.one;
import com.maps.one.*;
/**
 * 
　 * 
Title: Circle.java
 
　 * 
Description:圆形类继承抽象类 
 
　 * @author PoleYupro 
　 * @date 2019年9月27日
 */
public class Circle extends Graph{
     //圆形
	public double radius;

	public Circle(double radius){
     
		super();
		this.radius = radius;
	}
	public double getRadius() {
     
		return radius;
	}

	public void setRadius(double radius) {
     
		this.radius = radius;
	}
	
	
	public double area(){
     
		return 3.14*radius*radius;//Math.PI*radius*radius
	}
	
	public double girth(){
     
		return 3.14*2*radius;//Math.PI*2*radius
	}

}

Square.java

package com.maps.one;

public class Square extends Graph{
     //正方形
	public double side;

	
	public Square(double side) {
     
		super();
		this.side = side;
	}

	public double getSide() {
     
		return side;
	}

	public void setSide(double side) {
     
		this.side = side;
	}
	
	public double area(){
     
		return side*side;
	}
	public double girth(){
     
		return 4*side;
	}
}

Oblong.java

package com.maps.one;

public class Oblong extends Graph{
     //长方形
	public double length;
	public double width;
	
	public Oblong(double length, double width) {
     
		super();
		this.length = length;
		this.width = width;
	}
	
	public double getLength() {
     
		return length;
	}
	public void setLength(double length) {
     
		this.length = length;
	}
	public double getWidth() {
     
		return width;
	}
	public void setWidth(double width) {
     
		this.width = width;
	}
	
	public double area(){
     
		return length*width;
	}
	public double girth(){
     
		return 2*(length+width);
	}
}

MapsTest.java

package com.maps.one;
import java.util.Scanner;
import com.maps.one.*;

public class MapsTest {
     
	public static void main(String[] args){
     
		//圆
//		Circle cle = new Circle();
//		System.out.println("请输入圆的半径:");
//		Scanner sc = new Scanner(System.in);
//		cle.radius = sc.nextDouble();
//		System.out.println("圆形的面积为"+cle.area());
//		System.out.println("圆形的周长为"+cle.girth());
//		//正方形
//		Square sqe=new Square();
//		System.out.println("请输入正方形的边长:");
//		Scanner s=new Scanner(System.in);
//		sqe.side=s.nextDouble();
//		System.out.println("正方形的面积为"+sqe.area());
//		System.out.println("正方形的周长为"+sqe.girth());
//		//长方形
//		Oblong obl=new Oblong();
//		System.out.println("请输入长方形的长和宽:");
//		Scanner c=new Scanner(System.in);
//		obl.length=c.nextDouble();
//		obl.width=c.nextDouble();
//		System.out.println("长方形的面积为"+obl.area());
//		System.out.println("长方形的周长为"+obl.girth());
		
		Maps circle = new Circle(5.0);
		Maps square = new Square(4.0);
		Maps oblong = new Oblong(5.0,4.0);
		System.out.println("圆的面积为："+circle.area());
		System.out.println("圆的周长为："+circle.girth());
		System.out.println("正方形的面积为："+square.area());
		System.out.println("正方形的周长为："+square.girth());
		System.out.println("长方形的面积为："+oblong.area());
		System.out.println("长方形的周长为："+oblong.girth());
	}
}

题二

Comparable.java

package com.maps.two;
import com.maps.one.*;

public interface Comparable {
     
	
	//比较面积
	public int compareTo(Graph graph); 

}

MapsTest2.java

package com.maps.two;
import com.maps.one.*;
import com.maps.two.*;

public class MapsTest2 {
     
	
	public static void main(String[] args) {
     
		//实例化图形对象数组
		Graph[] gra = new Graph[10];
		for(int i=0;i<3;i++){
     
			Circle c = new Circle(2.0+i);
			gra[i] = c;
		}
		for(int i=3;i<7;i++){
     
			Square s = new Square(3.0+i);
			gra[i] = s;
		}
		for(int i=7;i<10;i++){
     
			Oblong o = new Oblong(3.0+i,4.0+i);
			gra[i] = o;
		}
		Graph max=gra[0];
		for(int i=0;i<gra.length;i++){
     
			if(gra[i].area()>max.area()){
     
				max = gra[i];
			}
		}
		System.out.println(max.area());
	}
}

简单总结

• 接口，抽象类的基本概念并理解
• 熟悉派生子类
• 对Java SE 阶段进行基础的复习