RFR 8200788 : Optimal initial capacity of java.lang.VarHandle.AccessMode.methodNameToAccessMode

[Paul Sandoz]

> On Apr 5, 2018, at 12:04 AM, Ivan Gerasimov <ivan.gerasimov at oracle.com> wrote:
> 
> Hello!
> 
> Yet another HashMap that can be preallocated more accurately.
> 
> Currently, the map is created as the following:
>            // Initial capacity of # values is sufficient to avoid resizes
>            // for the smallest table size (32)
>            methodNameToAccessMode = new HashMap<>(AccessMode.values().length);
> 
> Even though the comment suggests that no resizes of the table should occur, in fact the threshold is calculated as 32 * 0.75 = 24, so when 24th element is inserted then the internal storage is reallocated and the content of the table is reinserted.
> 

Thanks for fixing this.

I suspect that code and comment were written when there were fewer access modes.

Paul.

> Also, a missing @modules line is added to the regression test that was pushed with the fix for JDK-8200696.
> 
> Would you please help review this?
> 
> BUGURL: https://bugs.openjdk.java.net/browse/JDK-8200788
> WEBREV: http://cr.openjdk.java.net/~igerasim/8200788/00/webrev/
> 
> -- 
> With kind regards,
> Ivan Gerasimov
>