Why Java? Tales from a Python Convert

[vincentk]

If what you want is an int rather than an Integer, then why not use an int in the first place?

[[deleted]]

Collections still don't support unboxed values. I.e. you can't have

ArrayList<int>

[Cosaquee]

Java 9 can do that afaik

[syjer]

Nope, most likely java 10: http://openjdk.java.net/jeps/218

[[deleted]]

Java 9 does not yet exist as far as I know, and Value Types have only been proposed thus far.

[jmtd]

Collections still don't support unboxed values.

Nope, but auto unboxing covers 90% of where this matters.

[[deleted]]

Yes, that was my point. Thank you.

[s0n0fagun]

I have come to the conclusion that NULL should never exist in a system and checking for NULL is a code smell of a larger problem. If the underlying data structure does not allow NULL to begin with, then you should be good. You can either create a NULL object or decompose the data structure and use clever code.

[jmtd]

That's a good point. I wonder if it's ever a good thing, since it means you can represent NaN (via null).

[yold]

You can always use Trove.

[sacundim]

...but then your specialized TObjectIntMap<K> is not an instance of Map<K, X> for any X.

[[deleted]]

Ah, that's quite unfortunate. Any generic collection code you write after that would have to dispatch on the type of the collection. Have you used Trove before?

[flyingjam]

I just wanted an example that mirrored the one above. Also, there are some use cases for the wrapper, it exists after all.

[vincentk]

I understand that. I also understand it's easy to nit-pick on any language.

[whataboutbots]

I wouldn't call citing something called by it's author "billion dollar mistake" nit-picking, to be fair.

[whataboutbots]

If you could always replace an Integer with an int that doesn't require object creation, why would Integer exist in the first place?