尝试捕获块给出编译错误

Question

I am trying to add some of my code in try-catch block, but it fails at compilation and I am not getting what is wrong.

try 
{ 
    int x = 0; 
    int y = 5 / x; 
} 
catch (Exception e) 
{
    System.out.println("Exception"); 
} 
catch (ArithmeticException ae) 
{
    System.out.println(" Arithmetic Exception"); 
} 
System.out.println("finished");

Can anybody help please.

Answer 1

Use :

try 
{ 
    int x = 0; 
    int y = 5 / x; 
} 
catch (ArithmeticException ae) 
{
    System.out.println(" Arithmetic Exception"); 
} 
catch (Exception e) 
{
    System.out.println("Exception"); 
} 

System.out.println("finished");

While handling exceptions, wider exceptions(super class exception, in your case Exception is super class of ArthmeticException) must be catch after catching sub-class exceptions. Otherwise, exception will be caught by wider/parent exception catch block and latter code will be unreachable. So it will not compile.

Answer 2

exception hierearchy says

ONCE YOU HAVE CAUGHT AN EXCEPTION IT NEEDS NOT TO BE CAUGHT AGAIN

since you already are catching Exception in your first catch block

thus your next catch block is useless

you should catch child classes first , then for the remaining possible other exception should catch parent Exception class

try this

try 
{ 
    // your code throwing exception
} 
catch (ArithmeticException ae) 
{
    // do something
} 
catch (Exception e) 
{
    // do something
}