自定义异常练习（以银行的存款取款为例）

package com.zidingyi;

public class NewException extends Exception {
    
    public NewException()
    {
        System.out.println("账户余额不足，无法完成取款");
    }

}

package com.zidingyi;

public class Bank {
    //成员变量
    
    private double yue;
    

    public double getYue() {
        return yue;
    }


    public void setYue(double yue) {
        this.yue = yue;
    }
    
    
    //成员方法
    
    //存钱
    public double cunqian(double cun)
    {
        yue+=cun;
        return yue; 
    }
    
    //取钱
    public void quqian(double qu) throws NewException
    {
        if(qu>yue)
        {
            
            System.out.println("取款金额为："+qu);
            throw new NewException();
        }
        else
        {
            yue-=qu;
            System.out.println("取款金额为："+qu);
        }
    }


    public static void main(String[] args) {
        
        Bank b = new Bank();
        b.cunqian(100);
        try 
        {
            b.quqian(100);
        } 
        catch (Exception e) 
        {            
            e.printStackTrace();
        }
        System.out.println("账户余额为："+b.yue);

    }

}