testoverride.java

模拟电话卡的收费计费

public class TestOverride
{
	public static void main(String args[])
	{
		D200_Card my200 = new D200_Card(12345678,1234,50.0,"200");
		if(my200.performDial(12345678,1234))
			System.out.println ("拨打电话后剩余金额为："+my200.getBalance());
		if(my200.performDial())
			System.out.println ("拨打电话后剩余金额为:"+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;
	
	D200_Card(long cn,int pw,double b,String c)
	{
		cardNumber = cn;
		password = pw;
		balance = b;
		connectNumber = c;
	}
	boolean performDial()
	{
		if(balance>(0.5+additoryFee))
		{
			balance -= (0.5+additoryFee);
			return true;
		}
		else
			return false;
	}
	boolean performDial(long cn,int pass)
	{
		if(performConnection(cn,pass))
		{			
			return performDial();
		}
		else
			return false;
	}
	double getBalance()
	{
		if(connected)
			return balance;
		else
			return -1;
	}
}