streamed zip

[Tore Halset]

Hello.

I have a servlet that streams a zip archive to the client. It uses
java.util.zip.ZipOutputStream & co. It does not set the content
length header as the size is not known before the zip is created.

When a windows user clicks on a link to this servlet, she can
choose between "open" and "save". Save works very well, but
"open" does not. Using "open" just show an empty zip archive.

Anyone else seen this? Any known workaround?

Regards,
- Tore.

 

[Ingo R. Homann]

Hi,

I have a servlet that streams a zip archive to the client. It uses
java.util.zip.ZipOutputStream & co. It does not set the content
length header as the size is not known before the zip is created.

When a windows user clicks on a link to this servlet, she can
choose between "open" and "save". Save works very well, but
"open" does not. Using "open" just show an empty zip archive.

Anyone else seen this? Any known workaround?

I am not sure if this is really the problem, but some time ago, I
encountered a similar problem (or: "a different problem with a similar
effect"):

When "opening" some remote resource via IE, some IE versions seem do not
pass the 'response-stream' to the application, but rather pass the URL
of the 'resource' to the application which causes the application to
send a second request to the server. If the server is not able to handle
that, this will cause problems.

Ciao,
Ingo

 

[Tore Halset]

When "opening" some remote resource via IE, some IE versions seem do not
pass the 'response-stream' to the application, but rather pass the URL
of the 'resource' to the application which causes the application to
send a second request to the server. If the server is not able to handle
that, this will cause problems.

Thanks for the tip. I do not think this is the issue as the dialog show
that several MBs are downloaded.

The same problem happens with both MS Compressed Folders and with
WinZip 8.0 (I do not have a newer version).

- Tore.

 

[Tore Halset]

I have a servlet that streams a zip archive to the client. It uses
java.util.zip.ZipOutputStream & co. It does not set the content
length header as the size is not known before the zip is created.

When a windows user clicks on a link to this servlet, she can
choose between "open" and "save". Save works very well, but
"open" does not. Using "open" just show an empty zip archive.

Perhaps it is "Case 2" in this issue:
http://support.microsoft.com/?kbid=308090

Strange

- Tore.

 

[Tore Halset]

Perhaps it is "Case 2" in this issue:
http://support.microsoft.com/?kbid=308090

This fixed the problem:
res.setHeader("Cache-Control",
"must-revalidate, post-check=0, pre-check=0");

- Tore.