Sized (original) (raw)

Brian Goetz brian.goetz at oracle.com
Fri Nov 30 10🔞27 PST 2012

I've removed Sized from the implementation (since it is not adding the value it was supposed to) and have started migrating the streams methods to use longs for all size-related things.

Obviously, this is going to run into some difficulty at a few touch points:

The only place where we have to create an array is toArray, so I think its pretty reasonable to throw an exception when you try and create too big an array. The other times are when we're creating a fixed-sized result builder, in which case if the size is too big we can back off to a variable-sized one. If Collection.size() tells us it has MAX_INT, we should probably treat that as answering "I don't know my size." The middle case is likely to have a bug tail.

How much less than MAX_VALUE is the largest array size?

On 11/28/2012 7:19 AM, Doug Lea wrote:

On 11/27/12 19:50, Doug Lea wrote:

In other words, greater-than-int-sized collections are not a future possibility, but a reality that was a few years the subject of several collections bugfixes. That will also require stream bugfixes soon enough.

And to make this extra fun, the maximum array size you can create (for toArray etc) is less than Integer.MAXVALUE. See the odd constructions strewn around collection implementations that try to cope with this, but must still throw exceptions when coping fails. This will be needed for stream methods as well, regardless of Size-related APIs. -Doug

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