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Posted to log4cxx-user@logging.apache.org by LECHNER Martin <Ma...@frequentis.com> on 2005/02/01 11:44:47 UTC
Unicode Logging questions
Thanks to your help I was finaly able to compile the log4cxxd.dll.
I tried it out with logging of some unicode characters (japanese and german)
and have a few questions:
Is there a way to get readable chars instead of the unicode (\u4ECA) number
of the character?
What about uf8 encoding?
Did I miss some settings somewhere?
Best regards
ML
The result was for text mode:
2005-01-31 16:28:53,440[0x0000071D] INFO Main null - Configured test
Application: version:
2005-01-31 16:28:55,002[0x0000071D] INFO ***SCRAP*** null - Here we go!!!
2005-01-31 16:28:55,033[0x0000071D] ERROR ***SCRAP*** null - \u4ECAö
and for XML:
<log4j:event logger="Main" timestamp="1107185333440" level="INFO"
thread="0x0000071D">
<log4j:message><![CDATA[Configured test Application: version:
]]></log4j:message>
</log4j:event>
<log4j:event logger="***SCRAP***" timestamp="1107185335002" level="INFO"
thread="0x0000071D">
<log4j:message><![CDATA[Here we go!!!]]></log4j:message>
</log4j:event>
<log4j:event logger="***SCRAP***" timestamp="1107185335033" level="ERROR"
thread="0x0000071D">
<log4j:message><![CDATA[\u4ECAö]]></log4j:message>
</log4j:event>
Re: Re[2]: Unicode Logging questions
Posted by Curt Arnold <ca...@apache.org>.
On Feb 1, 2005, at 11:54 PM, Martin Lechner wrote:
> Hello Curt,
>
> Thanks for the info and tips.
> I can live with the \u representation for the moment, when I know that
> there will be readable output in the future.
>
> But I have another small question:
> I am currently replacing in an application std::string with
> std::wstring
> Before it was possible to log in streams, but with wstrings its not
> possible at the moment.
>
> works: LOG4CXX_DEBUG(loggerPtr_, "hello" << someString << 5 );
> works not: LOG4CXX_DEBUG(loggerPtr_, L"hello" << someWtring << 5 );
>
> Is this planned or do I have to use other ways to log things like
> this?
>
With the current CVS HEAD, neither is acceptable The log4cxx 0.9.7
macros were forced to create a stream to support this syntax even if
the argument was just a char* or std::string.
The current CVS's provides a stream wrapper for logging in
<log4cxx/stream.h>. The logstream class provides STL stream-like
semantics on top of a logger. The implementation supports
short-circuiting expressions when the level is not enabled. Due to the
non-atomic nature of stream operations, logstream is not thread-safe
(and can't be made so), so do not share it between threads. The
expected usage pattern is to have a static LoggerPtr as a class member
and logstream wrappers to be created on method entry. In addition, you
can insert either wchar_t or char strings into logstream, it will
transcode on the fly.
There is a sample in examples/stream.cpp and unit tests in
tests/src/streamtestcase.cpp. Your code fragment would should look
something like:
#include <log4cxx/stream.h>
class MyClass {
private static log4cxx::LoggerPtr
logger(log4cxx::Logger::getLogger("MyClass"));
public doSomething() {
log4cxx::logstream logstream(logger, log4cxx::Level::DEBUG);
logstream << L"hello" << someWstring << 5 << LOG4CXX_ENDMSG;
}
}
There has been a substantial amount of debate on the topic and still
profoundly different opinions on the desirable semantics which I do not
think can be reconciled in one implementation. I don't expect that the
semantics of log4cxx::logstream will change, but am open to
implementation improvements and am willing to consider including other
implementations, but I think we need to gather more experience and have
more platforms to test before doing that. You may want to review the
list dev archives and/or the Jira entry
(http://issues.apache.org/jira/browse/LOGCXX-18)
Re[2]: Unicode Logging questions
Posted by Martin Lechner <br...@sbox.tugraz.at>.
Hello Curt,
Thanks for the info and tips.
I can live with the \u representation for the moment, when I know that
there will be readable output in the future.
But I have another small question:
I am currently replacing in an application std::string with
std::wstring
Before it was possible to log in streams, but with wstrings its not
possible at the moment.
works: LOG4CXX_DEBUG(loggerPtr_, "hello" << someString << 5 );
works not: LOG4CXX_DEBUG(loggerPtr_, L"hello" << someWtring << 5 );
Is this planned or do I have to use other ways to log things like
this?
Best regards
ML
CA> That is the intent behind the Unicode rework, but not everything is
CA> fleshed out. The "\u4ECA" construct is generated by
CA> Transcoder::encode(const LogString& src, std::string& dst) when a
CA> character in src cannot be represented in the current code page.
CA> On Feb 1, 2005, at 4:44 AM, LECHNER Martin wrote:
CA> That is the intent behind the Unicode rework, but not everything is
CA> fleshed out. The "\u4ECA" construct is generated by
CA> Transcoder::encode(const LogString& src, std::string& dst) when a
CA> character in src cannot be represented in the current code page.
CA> In the case of the text file, you will get that form unless you specify
CA> an encoding that can represent the character (UTF-16 or UTF-8) using
CA> WriterAppender::setEncoding (or the equivalent configuration entry).
CA> However, support for arbitrary encodings hasn't been completed. I
CA> expect to implement it using APR-iconv shortly.
CA> I can probably fix the XML faster. Even though you could encode those
CA> characters as UTF-8 (since all XML processors are required to support
CA> UTF-8), it is probably preferable to represent non-USASCII characters
CA> as character entities (for example, &x4ECA;) since it would not be
CA> uncommon for users to try to open up a log file in a non-XML aware text
CA> editor or use a command line tool like cat.
--
Best regards,
Martin mailto:bruce_np@sbox.tugraz.at
Re: Unicode Logging questions
Posted by Curt Arnold <ca...@apache.org>.
On Feb 1, 2005, at 4:44 AM, LECHNER Martin wrote:
> Thanks to your help I was finaly able to compile the log4cxxd.dll.
>
> I tried it out with logging of some unicode characters (japanese and
> german)
> and have a few questions:
>
> Is there a way to get readable chars instead of the unicode (\u4ECA)
> number
> of the character?
That is the intent behind the Unicode rework, but not everything is
fleshed out. The "\u4ECA" construct is generated by
Transcoder::encode(const LogString& src, std::string& dst) when a
character in src cannot be represented in the current code page.
In the case of the text file, you will get that form unless you specify
an encoding that can represent the character (UTF-16 or UTF-8) using
WriterAppender::setEncoding (or the equivalent configuration entry).
However, support for arbitrary encodings hasn't been completed. I
expect to implement it using APR-iconv shortly.
I can probably fix the XML faster. Even though you could encode those
characters as UTF-8 (since all XML processors are required to support
UTF-8), it is probably preferable to represent non-USASCII characters
as character entities (for example, &x4ECA;) since it would not be
uncommon for users to try to open up a log file in a non-XML aware text
editor or use a command line tool like cat.