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    
  
    }  
}