Yes, it's about which exception it throws. `requir...

# announcements

[diesieben07]

Yes, it's about which exception it throws. require throws IllegalArgumentException, which makes no sense here, the arguments passed in to my methods were perfectly fine.

[ilya.gorbunov]

So, what exception do you want this function to throw?

[diesieben07]

In Guava they have a custom class that extends RuntimeException, which is the most reasonable thing you can do, I think.

[ilya.gorbunov]

To me it's more like an AssertionError — when the returned value doesn't meet the function contract.

[diesieben07]

Hm, true. However I am not sure if it's "correct" or "a good idea" to re-use AssertionError here, since that seems to be only for the assert keyword.

[dagguh]

I’m curious, why is the exception type important at all? Especially in a super-generic method like require.

Do you have a exception-type-specific try-catch logic? Limit the try scope and you’ll know what failed on your abstraction level. Or use return values instead of data-carrying exceptions.

Do you want the exception to explain the error? Let the exception message and stacktrace do it for you.

[diesieben07]

The exception type is not that important, a generic Exception would do. It's just that IllegalArgumentException and IlegalStateException are not appropriate, just like IOException isn't.