RFR 8005698 : Handle Frequent HashMap Collisions with Balanced Trees

Brent Christian brent.christian at oracle.com
Tue May 28 20:03:45 UTC 2013

On 5/28/13 3:09 AM, Doug Lea wrote:
> To better enable and simplify future improvements, could you
> do this -- nest the tree classes within HashMap?


> Also, a note on spliterators: I had added these in the
> least disruptive way (knowing that major changes were coming)
> by checking exact class match for HashMap.class. This is because
> there aren't LinkedHashMap view classes to attach overrides to.
> While not wrong, and OK for now, at some point this should be redone.

OK.  I will file a bug so this doesn't get forgotten.

I also applied the change to how HashMap.putAll() resizes the table (to 
account for splitTreeBin() only handling doubling of tables).

The updated webrev is here:



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