自定义抛出throw 对象练习

package ltb6w;
import java.util.*;

public class Bank {

    private String select;
    private String select2;

    private double balance=0.0; //余额
    private double inputbalance=0.0;

    private Scanner sc=new Scanner(System.in);

    public Bank() {

        System.out.println("请输入存款额度:");

    }

    @SuppressWarnings("serial")
    class  NotSufficientFunds extends Exception { //自定义异常类

        private String insufficient;

        NotSufficientFunds(String s ) {

            insufficient=s;
        }

        public String getMessage() {

            return insufficient;

        }

    }                                              

    public void deposite() throws Exception{//存款操作

        inputbalance=sc.nextInt();

        if(inputbalance<0) {

            throw new NotSufficientFunds("存款不能是负数");  //抛出自定义异常
        }

        this.balance=inputbalance+balance;

        System.out.println("存款总额:"+balance);
    }        

    public void withdrawa() throws Exception{//取款操作

        System.out.println("请输入取款数:");

        this.balance=balance-sc.nextInt();

        if (balance<0) { //激发异常类

                throw new NotSufficientFunds("余额已经是负数了"); 

        }    

        System.out.println("余额:"+this.getbalawal());
    }            

    public double getbalawal() { //获取余额操作

        return balance;
    }

    public static void main(String[] args) {

        Bank b=new Bank();

        while (true) {  

            try {
                b.deposite();
            } catch (Exception e) {

                e.printStackTrace();
            }

            System.out.println("是否继续存款：是or否");

            try {
                b.select=b.sc.next(); // 容易出异常的地方

            }catch (InputMismatchException e) {

                System.out.println("不要输入(是or否)之外无关的存款数据，从来，再来。");

                continue;

            }

            if("否".equals(b.select)) {    

            while (true) {

                System.out.println("看仔细了！！！是否还继续取款：是or否");

                try {
                    b.select2=b.sc.next(); // 容易出异常的地方

                }catch (InputMismatchException e) {

                    System.out.println("不要输入(是or否)之外无关的数据，从来，再来。");

                    continue;

                }

                if("是".equals(b.select2)) {

                    try {
                        b.withdrawa();

                        break;
                    } catch (Exception e) {

                        e.printStackTrace();
                    }

                }else if ("否".equals(b.select2)){

                    System.out.println("不管你选不选否都当做退出。["+b.select2+"]");

                    break;
                }

            }    

            System.out.println("已经成功退出");

              break;

            }else if("是".equals(b.select)) {
                System.out.println("继续输入金额，come on baby!");
            }

        }

    }

}