构造品数示例 5-17 PhoneCard(long cn,int pw,double b,String s) cardNumber cn; password pw; if (b>0) balance b; else System.exit(1); connectNumber s; connected false; PhoneCard newCard new PhoneCard(12345678,1234,50.0,”300); Programming in Java JAVA5-17 Programming in Java 构造函数示例 PhoneCard(long cn, int pw, double b, String s) { cardNumber = cn; password = pw; if (b > 0) balance = b; else System.exit(1); connectNumber = s; connected = false; } • PhoneCard newCard = new PhoneCard(12345678,1234,50.0,”300”);