map and null values

Sam Pullara sam at
Thu Jan 3 19:15:59 PST 2013

I agree. Walk away from null keys + values and don't look back.


On Thu, Jan 3, 2013 at 7:09 PM, Jed Wesley-Smith <jed at> wrote:

> It should fairly clear by now that the decision to allow a null key
> and null values in the Map interface was a mistake and should not be
> continued. Null-intolerance – particularly now there is an Optional
> class that solves partiality properly – is not only ok but should be
> the default, promoted position.
> Concurrency simply makes the overloading of null to mean something and
> nothing more obviously absurd.
> If we can agree that nulls should essentially be deprecated as a legal
> value or key then we avoid all the complicated gymnastics this thread
> shows are necessary to support them.
> cheers,
> jed.

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