• 练习9(第九章习题)


    package cn.ch.w;
    
    public class TestSimpleCircle {
        private double radius;
    
        // 构造方法,有参构造
        public void Circle(double radius) {
            this.radius = radius;
        }
        //方法的重载,参数不同
        // 构造方法,无参构造
        public void Circle() {
            this.radius = 1;
        }
    
        // 求圆面积的方法
        public double getArea() {
            return radius * radius * Math.PI;
    
        }
    
        // 求圆周长的方法
        public double getPerimeter() {
            return 2 * Math.PI * radius;
        }
        public void setRadius(double newRadius) {
            this.radius=newRadius;
        }
    }
    package cn.ch.w;
    
    public class DemoCircle {
         public static void main(String[] args) {
                 TestSimpleCircle circle1=new TestSimpleCircle();
                double area=circle1.getArea();
                System.out.println(area);
                TestSimpleCircle circle2=new TestSimpleCircle();
                System.out.println(circle2.getArea());
                System.out.println(circle1.getPerimeter());
                System.out.println(circle2.getPerimeter());
                double ridius=10;
                double areaCircle=Math.PI*ridius*ridius;
                System.out.println(areaCircle);
                circle2.setRadius(5);
                System.out.println(circle2.getArea());
            }
    
    
    }

    9-2

    package cn.ch.w;
    
    public class SimpleCircle {
        private double radius;
        public SimpleCircle() 
        {
            this.radius=1;
        }
        public SimpleCircle(double radius)
        {
            this.radius=radius;
        }
        public double getArea() 
        {
    
            return Math.PI*radius*radius;
        }
        public double getPerimeter() 
        {
            return 2*Math.PI*radius;
        }
        
        public static void main(String[] args)
        {
            SimpleCircle cir1=new SimpleCircle();
            System.out.println("半径是"+cir1.radius+"面积是"+cir1.getArea());
            SimpleCircle cir2=new SimpleCircle(10);
            System.out.println("半径是"+cir2.radius+"面积是"+cir2.getArea());
        }
    
    
    }

    9-3

    package cn.ch.w;
    
    public class TV {
        public int channel=1;
        public int volumeLevel=1;
        public boolean on=false;
        
        public TV() {
            
        }
        public void turnOn() 
        {
            on =true;
            System.out.println("电视已开启!!");
        }
        public void turnOff() 
        {
            on=false;
            System.out.println("电视已关闭!!");
        }
        public int getChannel() 
        {
            return channel;
        }
        public void setChannel(int channel) 
        {
            if(on) 
            {
                System.out.println("电视机已开,可以调试了。");
                if(channel>=1&&channel<=120) 
                {
                    this.channel = channel;
                    System.out.println("频道已在"+channel+" 台");
                }else 
                {
                    System.out.println("频道不存在!!");
                }
            }else 
            {
                System.out.println("白痴主人电视开启才可以调试");
            }
        }
        public int getVolumeLevel() 
        {
            return volumeLevel;
        }
        public void setVolumeLevel(int volumeLevel) {
            if(on) {
                System.out.println("电视已开,声音已可调试");
                if(volumeLevel>=1&&volumeLevel<=7) {
                    this.volumeLevel = volumeLevel;
                    System.out.println("声音设置成了 "+volumeLevel+" 大小");
                }
            }else 
            {
                System.out.println("白痴主人电视开启才可以调试");
            }
            
        }
        public void channelUp() 
        {
            if(on&&channel<120) 
            {
                channel++;
            }
        }
        public void channelDown()
        {
            if(on&&channel>1) 
            {
                channel--;
            }
        }
        public void volumeUp() 
        {
            if(on&&volumeLevel<7) 
            {
                volumeLevel++;
            }
        }
        public void volumeDown() 
        {
            if(on&&volumeLevel>1) 
            {
                volumeLevel--;
            }
        }
    
    
    }
    package cn.ch.w;
    
    public class testTV {
        public static void main(String[] args) {
         TV tv1=new TV();
         tv1.turnOff();
         tv1.setChannel(30);
         tv1.setVolumeLevel(3);
          
          TV tv2=new TV();
          tv2.turnOn();
          System.out.println("电视节目是"+tv2.channel+"声音是"+tv2.volumeLevel);
          tv2.channelUp();
          System.out.println("电视节目是"+tv2.channel+"声音是"+tv2.volumeLevel);
          tv2.channelUp();
          System.out.println("电视节目是"+tv2.channel+"声音是"+tv2.volumeLevel);
          tv2.channelUp();
          System.out.println("电视节目是"+tv2.channel+"声音是"+tv2.volumeLevel);
          tv2.volumeUp();
          System.out.println("电视节目是"+tv2.channel+"声音是"+tv2.volumeLevel);
          tv2.volumeUp();
          System.out.println("电视节目是"+tv2.channel+"声音是"+tv2.volumeLevel);
          tv2.volumeUp();
          System.out.println("电视节目是"+tv2.channel+"声音是"+tv2.volumeLevel);
          
          
      }
    
    
    }

  • 相关阅读:
    学姐学长们的测试
    loli的测试——搜索
    搜索-2
    单调队列
    乱搞题 (不知道怎么分类)
    对拍及数据生成
    搜索-1
    矩形重叠
    拼写单词
    java笔记
  • 原文地址:https://www.cnblogs.com/zr1636050087/p/7800753.html
Copyright © 2020-2023  润新知