第8周作业1——类与对象练习之TV

版权声明：本文为博主原创文章，未经博主允许不得转载。 https://blog.csdn.net/u013907419/article/details/24654653

//类与对象的练习，定义TV类的程序
public class TV {
	int channel =1;//Default channel is 1
	int volumelevel =1;//Default volume level is 1
	boolean on = false;//By default TV off
	/*public String volumeLevel;因为按书本之前的代码写进去，而书本的volumeLevel中的l大写了，因此多此一句代码，
	 * 而结果也不一样，
	所以我认定书本有误了*/
	
	public TV(){
	}

	public void turnOn(){
		on =true;
	}

	public void turnOff(){
		on = false;
	}

	public void setChannel(int newChannel){
		if(on && newChannel >=1 && newChannel <=120)
			channel = newChannel;
	}

	public void setVolume(int newVolumeLevel){
		if(on && newVolumeLevel >=1 && newVolumeLevel <=7)
			volumelevel = newVolumeLevel;
	}

	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--;
	}
}

//使用TV类程序创建两个对象的程序
public class TestTV {
	public static void main(String[] args){
		TV tv1 = new TV();
		tv1.turnOn();
		tv1.setChannel(30);
		tv1.setVolume(3);

		TV tv2 = new TV();
		tv2.turnOn();
		tv2.channelUp();
		tv2.channelUp();
		tv2.volumeUp();

		System.out.println("tv1's channel is "+ tv1.channel 
				+ " and volume level is "+ tv1.volumelevel);
		System.out.println("tv2's channel is "+ tv2.channel
				+ " and volume level is "+ tv2.volumelevel);
	}
}