java 如何自定义异常 用代码展示 真心靠谱

先建两个自定义的异常类

ChushufuException类

class ChushufuException extends Exception
{
    public ChushufuException(String msg)
    {
        super(msg);
    }
} 

ChushulingException

class ChushulingException extends Exception
{
    public ChushulingException(String msg)
    {
        super(msg);
    }
}

好了，然后再写一个测试类Numbertest

class Numbertest
{
    public int shang(int x,int y) throws ChushulingException,ChushufuException
    {
        if(y<0)
        {
            throw new ChushufuException("xxxxxxxxxxx您输入的是"+y+",规定除数不能为负数!");//抛出异常
        }
        if(y==0)
        {
            throw new ChushulingException("您输入的是"+y+",除数不能为0!");
        }  

        int m=x/y;
        return m;
    }
}

是不是很简洁明了？

再来一个测试类

class Rt001
{
    public static void main(String[]args) throws ChushulingException
    {
        Numbertest n=new Numbertest();
    	Logger logger = Logger.getLogger(Rt001.class.getName());
        //捕获异常
        try
        {
            System.out.println("商="+n.shang(1,-3));
        }
//        catch(ChushulingException yc)
//        {
//            System.out.println(yc.getMessage());
//            yc.printStackTrace();
//        }
        catch(ChushufuException yx)
        {
            System.out.println(yx.getMessage());
            yx.printStackTrace();
            logger.error("oops, got an exception: ",yx);
        }
//        catch(Exception y)
//        {
//            System.out.println(y.getMessage());
//            y.printStackTrace();
//        }  

    //finally{ System.out.println("finally!");} ////finally不管发没发生异常都会被执行    

    }
}