http://javaweb.sfbay.sun.com/~sherman/6332094/

[Martin Buchholz]

On Fri, May 14, 2010 at 19:24, Xueming Shen <xueming.shen at oracle.com> wrote:
> Martin Buchholz wrote:
>>
>> Well, the obvious thing to do is to use ZipFile,
>> and if something goes wrong,
>> back off and try the old implementation with
>> ZipInputStream in addition.
>>
>>
>
> I will add a check like
>
> if (fname != null && new File(fname).length() < 0x100000000L)
>   go ZipFile;
> else
>   go ZipInputStream

Sounds good.

hmmm....
If the input zip file is actually a ZIP64 file for some other reason
(for example to get >64k entries), then ZipInputStream
will still succeed, while ZipFile will probably fail,
in which case the fallback algorithm might be more robust.

But I am happy with any action on your part,
including doing nothing.

>
>> If the JDK has ZIP64 support,
>> what goes wrong?
>>
>>
>
> Nothing goes wrong with ZIP64, but we don't have that in 6u (yet)

Oh, right.  And a backport of ZIP64 support probably isn't
worth the risk and effort.

Martin

> -Sherman
>
>
>> Martin
>>
>> On Fri, May 14, 2010 at 16:18, Xueming Shen <xueming.shen at oracle.com>
>> wrote:
>>
>>>
>>> It appears the backport to 6u of the optimization we did in #6332094
>>> breaks
>>> someone's code.
>>>
>>> Obviously the ZipInputStream works fine with >4G zipfile even without the
>>> ZIP64 format support
>>> as long as the individual zip entries inside is smaller than the 4G
>>> limit,
>>> so the sequential reading in jar's
>>> old implementation just works "fine" with the >4G zip. But the
>>> optimization
>>> we put in to use ZipFile
>>> instead causes the regression because it needs the access to the 64bit
>>> central directory table if the
>>> zip is > 4G. While it is arguable if a > 4G zipfile without the ZIP64
>>> extension table is a "correctly"
>>> formatted zip file or in fact that jar can never create a > 4G zip file
>>> before we added the ZIP64
>>> support, regression is a regression:-(
>>>
>>> I believe you also backport the same thing into 6open.
>>>
>>> -Sherman
>>>
>>>
>
>