6 Apr
2007
6 Apr
'07
2:54 p.m.
On 4/6/07, Vincent Massol <vincent(a)massol.net> wrote:
Hi,
I admit it: I'm not an expert in I8N. However I realize that XWiki
being a wiki we need to have strong I8N features so I'm trying to
catch up with I8N knowledge...
I started yesterday by reading this excellent short tutorial http://
www.joelonsoftware.com/articles/Unicode.html (The Absolute Minimum
Every Software Developer Absolutely, Positively Must Know About
Unicode and Character Sets (No Excuses!)). It's very good and an easy
read. I recommend it to everyone.
It's a bit too short, just when things get interesting, it ends.
This led me to a few questions:
1) Is UTF8 supported on all platforms? Is it supported on mobile
platforms for example?
Platforms old enough not to know UTF are unlikely to support running XWiki
on it.
2) I see in our encoding guide on http://www.xwiki.org/xwiki/bin/view/
AdminGuide/Encoding that we need to set the encoding
for the
container. Why is that required? The servlet container reads pages
which have the encoding specified (using Content-Type meta data), so
why does it need to be told about the encoding to use?
If you mean the parameter in web.xml, then it's not the container encoding,
but a parameter used to correctly identify outgoing files (it sets the
Content-Type header according to this param).
There are more files which don't have a Content-Type. First there are the
files stored on disk. Second, when you POST some data or GET a resource, you
don't have a content type. Requests don't have this HTTP header.
3) I see that in our standalone installation we use -
Dfile.encoding=iso-8859-1. Now that I've read
Joel's tutorial it
seems to me this is not going to work for everyone and that we should
rather use -Dfile.encoding=UTF-8 by default. WDYT?
UTF-8 is better. But we really should not depend on the file encoding.
4) Should we use the platform encoding or default to using UTF-8 all
the time? (this question is related to 1)). I think we
should use the
platform encoding but I'm curious to know what others think.
UTF-8 all the time. Thus we have no dependency on the system, and we don't
need guides on "how to change the encoding in only 7 places to make my wiki
know bulgarian"
5) Jackson Wang is proposing in a patch to modify readPackage like this:
private Document readPackage(InputStream is) throws
IOException, DocumentException
{
- byte[] data = new byte[4096];
+ //UTF-8 characters could cause encoding as continued bytes
over 4096 boundary,
+ // so change byte to char. ---Jackson
+ char[] data = new char[4096];
+ BufferedReader in= new BufferedReader(new InputStreamReader
(is));
StringBuffer XmlFile = new StringBuffer();
int Cnt;
- while ((Cnt = is.read(data, 0, 4096)) != -1) {
+ while ((Cnt = in.read(data, 0, 4096)) != -1) {
XmlFile.append(new String(data, 0, Cnt));
- }
+ }
return fromXml(XmlFile.toString());
}
However with my new understanding I'm not sure this would help as
char are stored on 2 bytes in Java and UTF-8 encoding can store on up
to 4 bytes. Am I correct?
However, I would rather use http://jakarta.apache.org/commons/io/api-
release/org/apache/commons/io/IOUtils.html#toString
(java.io.InputStream) than code it ourselves... Sounds safer,
shorter, less maintenance, etc to me... :)
+1. Always reuse existing proven code than reinvent a squeaky wheel.
Thanks for your help
-Vincent
Sergiu
--
http://purl.org/net/sergiu