例子：

 --异常捕获级别

 throw用在方法中 throwd在方法上抛出异常

package oop.exception;
public class Demo1 {
    public static void main(String[] args) {
        int a=1;
        int b=0;
        //ctrl+alt+t 异常快捷键
        //捕获异常
        try {
            System.out.println(a / b);
        } catch (Error e) {
            System.out.println("Error");
            //打印异常 e.printStackTrace();
        }
        catch (Exception e) {
            System.out.println("Exception");
        } catch (Throwable e) {
            System.out.println("Throwable");
        }
        finally {
            System.out.println("finally");
        }
        //test方法中的捕获异常
        try {
            test(1,0);
        } catch (ArithmeticException e) {
            System.out.println("asdasfasfasfas");
        } finally {
            System.out.println("finally");
        }
 
    }


    public static void test(int a,int b) throws  ArithmeticException {
        if (b==0) {
            System.out.println("asd");
            throw new ArithmeticException();
        }
    }

}

自定义异常