optimising OUString for space

[Noel Grandin]

On 2012-10-01 13:25, Michael Meeks wrote:
>> The latest Java VM does this trick internally - it pretends that String
>> is stored with an array of 16-bit values, but actually it stores them as
>> UTF-8.
> 	Interesting - for all strings ? is there a pointer to the code / docs
> for that detail somewhere ? :-)
It's a "magic" thing. The VM overrides the language level definition of 
java.lang.String with it's own.

Hmm, pity, looks like they introduced it in JDK6 and then dropped it in 
JDK7.
http://stackoverflow.com/questions/8833385/is-support-for-compressed-strings-being-dropped
Looks like the backwards compatibility overhead was too high.


> Last I looked Java also stored partial
> strings chained to it's parent; so 'substring' takes a reference on the
> parent (be it ever so large), and can return a single character string
> out of it without re-allocation. IIRC that can cause huge grief when
> parsing big files into little ones ;-)
>
That "optimisation" is being dropped in JDK8, for precisely that reason.

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