定义一个圆柱体类cylinder，并创建相应的对象，然后计算圆柱体的底面积与体积

川长思鸟来 2022-09-02 01:14 213阅读 0赞

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L20wXzU4MTM4NzM0_size_16_color_FFFFFF_t_70][]

**输入**

2.8
    5

package com;
    import java.util.*;
    class cylinder
    {
        double radius;
        int height;
        double pi=3.14;
        void area() {
            System.out.println("底面积=" + pi * radius * radius);
        }
        double volume()
        {
            return (pi*radius*radius)*height;
        }
    }
    public class sentence {
        public static void main(String[] args) {
            cylinder volu;
            volu=new cylinder();
            Scanner reader=new Scanner(System.in);
            System.out.println("请输入圆柱的半径：");
            volu.radius= reader.nextDouble();
            System.out.println("请输入圆柱的高：");
            volu.height=reader.nextInt();
            System.out.println("低圆半径="+volu.radius);
            System.out.println("圆柱的高="+volu.height);
            System.out.print("圆柱");
            volu.area();
            System.out.println("圆柱体体积="+volu.volume());
        }
    }

**以圆柱类cylinder为例在类内部调用自己的方法**

import java.util.*;
    class cylinder
    {
        double radius;
        int height;
        double pi=3.14;
        double area() {
           return pi * radius * radius;
        }
        double volume()
        {
            return area() * height;
        }
    }
    public class sentence {
        public static void main(String[] args) {
            cylinder volu;
            volu=new cylinder();
            Scanner reader=new Scanner(System.in);
            System.out.println("请输入圆柱的半径：");
            volu.radius= reader.nextDouble();
            System.out.println("请输入圆柱的高：");
            volu.height=reader.nextInt();
            System.out.println("低圆半径="+volu.radius);
            System.out.println("圆柱的高="+volu.height);
            System.out.print("圆柱");
            System.out.println("底面积=" +volu.area());
            System.out.println("圆柱体体积="+volu.volume());
        }
    }

**进一步，如果要强调是对象本身的成员话，则可以在成员名前加this关键字。即this.成员名**

**this代表调用此成员的对象**

double volume()
        {
            return this.area() * height;
        }

**在圆柱体类cylinder中用变量调用方法**

class cylinder
    {
        double radius;
        int height;
        double pi=3.14;
        void setcylinder(double r,int h,double p)
        {
            pi=p;
            radius=r;
            height=h;
        }
        double area() {
           return pi * radius * radius;
        }
        double volume()
        {
            return this.area() * height;
        }
    }
    public class sentence {
        public static void main(String[] args) {
            double r;int h;
            cylinder volu;
            volu=new cylinder();
            Scanner reader=new Scanner(System.in);
            System.out.println("请输入圆柱的半径：");
            r=reader.nextDouble();
            System.out.println("请输入圆柱的高：");
            h=reader.nextInt();
            volu.setcylinder( r, h,3.14);
            System.out.println("低圆半径="+volu.radius);
            System.out.println("圆柱的高="+volu.height);
            System.out.print("圆柱");
            System.out.println("底面积=" +volu.area());
            System.out.println("圆柱体体积="+volu.volume());
        }
    }

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L20wXzU4MTM4NzM0_size_16_color_FFFFFF_t_70]: /images/20220829/84c1ff46771440d5a23b6351798fe4ee.png