自定义异常

1.继承现有的异常结构，RuntimeException，Exception

2.提供全局常量：serialVersionUID

3.提供重载的构造器

 

自定义异常类

public class MyException extends Exception{
    static final long serialVersionUID = -3387512393124229948L;

    public MyException(){
        super();
    }

    public MyException(String msg){
        super(msg);
    }

}

　　

测试类

public class ExceptionTest {

    public static void main(String[] args) {
        try {
            method(-10);
        } catch (MyException e) {
            e.printStackTrace();//MyException: 负数异常
        }
    }


    public static void method(int num) throws MyException{
        if(num>0){
            System.out.println(num);
        }else{
            throw new MyException("负数异常");
        }
    }
}