Return statement just after a catch bloc ?

[red light]

What would happen in the following method in case of try..catched exception, that will throw an exception ? Notice the return 0; is it unreachable ?

public int calculateAmount(Data data, int coefficient){

  try {
    int price = 0;
    // do something 
    price *= executeCalculation(data.getBase(), coefficient);
    return price;
  } catch (Exception ex) {
    throw new IllegalArgumentException("some params aren't valid");
  }

  return 0; // is this unreacheable in case of exception ?
}

[frank dagger]

Detected code, here are some useful tools:

<@&987246883653156906> please have a look, thanks.

[indigo swan]

yeah seems like it is unreachable to me

I think you can even remove it iirc

java should be able to tell that it is unreachable

[red light]

it said no

ah i know why

thanks

[frank dagger]

Closed the thread.

[indigo swan]

I tested it

and it gave me an error

based on specs

[red light]

oh it gaves error

i thought it'd do warn only

[indigo swan]

also dont catch Exception please

[red light]

why not ?

[indigo swan]

Exception literally catches everything, instead catch the specific exception

especially because you afterwards throw IllegalArgumentException though you cant be sure the exception comes from that

[red light]

i know all the possible exceptions from the code inside the try

there are some method calls that have their own try..catch

and generally, the possible exceptions are about args

[indigo swan]

yeah, then catch these specific exceptions instead

also I personally would use proper validation using if + throw illegalargumentexception instead

[red light]

im doing something like this

if(ex instanceof SomeException someException){
 error = "something went wrong while trying to ";
}

[frank dagger]

Detected code, here are some useful tools:

[red light]

and a general message if none are matched

[indigo swan]

you really doing instanceof checks on exceptions?

that looks like a bad design

[red light]

give why or it's odd

[indigo swan]

because try catch exists

to catch specific exceptions

[red light]

and general ones

[indigo swan]

just because its possible doesnt mean its good

[red light]

https://stackoverflow.com/a/20431728/10000150

[indigo swan]

thats pre optimizing

also I am not talking about speed

speed is completely irrelevant here

also that answer is from 2013

just so you know

[red light]

hm

[indigo swan]

https://stackoverflow.com/questions/27280928/how-to-check-which-exception-type-was-thrown-in-java

for example this one

says something completely different

[red light]

alr , the dude is using instanceof

¯_(ツ)_/¯

[indigo swan]

not really

[red light]

https://stackoverflow.com/a/27280953/10000150

[indigo swan]

read the first sentence

literally

lol

read

not just look at the code

[red light]

..unless you need to share some steps in common

i need that

[indigo swan]

ok, though I would disagree with that sentence in some cases

where a method makes more sense

but notice how its not catching Exception

but the specific exceptions

catch (NotAnInt | ParseError e)

[red light]

i know , that looks better maybe, but using instanceof does the same

[indigo swan]

and a finally block maybe makes sense as well

but again cant really tell without real context

if someone needs instanceof checks with exceptions there is usually a design issue in the first place

[civic spade]

Why do you not just multicatch them

[civic spade]

No you don't
You can't know if you have bugs

[red light]

i mean checked ones

the unchecked ones, will have a general message

alright, im gonna explain my point here

[indigo swan]

not every exception should have a general message though

some might be a serious bug

and you silent them

by creating a general message

[red light]

if i use multicatch blocs:

try {
  // do something that may fire exception(s)
} catch (ExceptionA ex) {
  log.erro("something went wrong while trying to do A")
  throw new illegalArgException(ex.message());
} catch (ExceptionB ex) {
  log.erro("something is wrong while trying to do B")
  throw new illegalArgException(ex.message());
}  catch (ExceptionC ex) {
  log.erro("something is wrong while trying to do C")
  throw new illegalArgException(ex.message());
}

[frank dagger]

Detected code, here are some useful tools:

[red light]

good point, this is generally to not bother server logs when app is deployed in QA or prod

a friendly msg would help to start investigating rather than technical and lengthy one

as for dev environment, yes, i'd print stacktrace

[indigo swan]

a generic message going to get ignored lol

[red light]

maybe, but certainly not, when users complaint

and a bug is issued

to sumup the design of an app is not only for dev purpose, it must care about other envs

[red light]

btw, it's by Intellij suggestion i switched to do catch(Exception ex) {}

alright thanks for your help