testoverload.java

模拟电话卡的收费计费

public class TestOverLoad
{
	public static void main(String args[])
	{
		D200_Card my200 = new D200_Card();
		my200.balance = 50.0;
		System.out.println ("父类被隐藏的金额为:"+my200.getBalance());
		if(my200.performDial())
			System.out.println ("子类的剩余金额为:"+my200.balance);
	}
}


abstract class PhoneCard
{
	double balance;
	abstract boolean performDial();
	double getBalance()
	{
		return balance;
	}
}

abstract class Number_PhoneCard extends PhoneCard
{
	long cardNumber;
	int password;
	String connectNumber;
	boolean connected;
	
	boolean performConnection(long cn,int pw)
	{
		if(cn == cardNumber&&pw == password)
		{
			connected = true;
			return true;
		}
		else
			return false;
	}
}

class D200_Card extends Number_PhoneCard
{
	double additoryFee;
	double balance;
	boolean performDial()
	{
		if(balance>(0.5+additoryFee))
		{
			balance -= (0.5+additoryFee);
			return true;
		}
		else
			return false;
	}
	double getBalance()
	{
		return balance;
	}
}