Sized

[Doug Lea]

On 11/30/12 13:25, Kevin Bourrillion wrote:
> When I tried it you can go up to MAX_VALUE - 5.

We use (I think everywhere in java.util.* where it applies),
the slightly more conservative:

static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8;

-Doug


>
>
> On Fri, Nov 30, 2012 at 1:18 PM, Brian Goetz <brian.goetz at oracle.com
> <mailto:brian.goetz at oracle.com>> wrote:
>
>     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:
>       - creating arrays
>       - indexing into arrays
>       - when Collection.size() lies (because it is clamped at MAX_INT)
>
>     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.MAX_VALUE. 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
>
>
>
>
>
> --
> Kevin Bourrillion | Java Librarian | Google, Inc. |kevinb at google.com
> <mailto:kevinb at google.com>
>