类：实验2家中的电视

TV类

public class TV
{
	int channel;
	void setChannel(int m)
	{
		if(m>=1)
		{
			channel=m;
		}
	}
	int getChannel()
	{
		return channel;
	}
	void showProgram()
	{
		switch(channel)
		{
			case 1:System.out.println("综合频道");
			break;
			case 2: System.out.println("经济频道");
			break;
			case 3: System.out.println("文艺频道");
			break;
			case 4: System.out.println("国际频道");
			break;
			case 5: System.out.println("体育频道");
			break;
			default : System.out.println("不能收看"+channel+"频道");
		}
	}
}

Family 类

public class Family
{
	TV homeTV;
	void buyTV(TV tv)
	{
		homeTV=tv;
	}
	void remoteControl(int m)
	{
		homeTV.setChannel(m);
	}
	void seeTV()
	{
		homeTV.showProgram();
	}
}

主类：

public class MainClass
{
	public static void main(String args[])
	{
		TV haierTV = new TV();
		haierTV.setChannel(5);
		System.out.println("haierTV的频道是"+haierTV.getChannel());
		Family zhangSanFamily = new Family();
		zhangSanFamily.buyTV(haierTV);
		System.out.println("zhangSanFamily开始看电视节目");
		zhangSanFamily.seeTV();
		int m=2;
		System.out.println("zhangSanFamily将电视更换到"+m+"频道");
		zhangSanFamily.remoteControl(m);
		System.out.println("haierTV的频道是"+haierTV.getChannel());
		System.out.println("zhangSanFamily再看电视节目");
		zhangSanFamily.seeTV();
	}
}