1）在定义一个银行类 Bank 时, 有 deposit、withdraw、showBalance 等方法。若取钱数大于余额则作为异常处理(InsufficientFundsException)。产生异常的条件是余额少于取额，因此是否抛出异常要判断条件，要定义好自己的异常类。package ex91;public class Bank public double total=0; Bank(double d) total=d; public void deposit(double d) total+=d; public void withdraw(double d) total-=d; public void showBalance() System.out.println(total); package ex91;public class BankException extends Exception String message; Ban
