How to use log4cplus as a custom singleton class

Question

0.00/5 (No votes)

See more:

Following is my code:

C++

class LogCp
{
public:

	~LogCp();
	static LogCp& GetInstance();
	static Logger _logger;

private:
	LogCp();
	LogCp(const LogCp&) = delete;
	void operator =(LogCp const&);

};

C++

Logger LogCp::_logger = log4cplus::Logger::getInstance(LOG4CPLUS_TEXT("filelogger"));
//Logger LogCp::_logger = log4cplus::Logger::getRoot();	

LogCp::LogCp()
{
	log4cplus::Initializer initializer;
	try {
		PropertyConfigurator::doConfigure(LOG4CPLUS_TEXT("E:\\log4cplus.properties"));
		//_logger = log4cplus::Logger::getInstance(LOG4CPLUS_TEXT("filelogger"));
		LOG4CPLUS_WARN(_logger, LOG4CPLUS_TEXT("logging...."));
	}
	catch (...) {
		LOG4CPLUS_FATAL(_logger, LOG4CPLUS_TEXT("Exception occured..."));
	}
}

LogCp& LogCp::GetInstance()
{
	static LogCp vLogCp;
	return vLogCp;
}

LogCp::~LogCp()
{

}

the main func:

C++

void logInitial()
{
	LogCp::GetInstance();
   
}

int main(int argc, wchar_t* argv[])
{
	logInitial();
	LOG4CPLUS_WARN(LogCp::GetInstance()._logger, LOG4CPLUS_TEXT("test"));
}

It can log correctly in constructor function,but it won't log "test" in main() function unless I add doConfigure() function again before LOG4CPLUS_WARN.why?

What I have tried:

read lots of similar questions but still cannot resolve this

Posted 24-Nov-16 23:52pm

TimGallin

Updated 25-Nov-16 1:02am

Add a Solution

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

KarstenK · Answer 1 · 2016-11-25T01:02:00

Solution 1

The scope or lifetime of your LogCp doesnt cover the main scope. It is essential to understand that issues. It is also very important if working with pointers and objects.

This should solve your problem:

C++

int main(int argc, wchar_t* argv[])
{
	LogCp::GetInstance();// create in scope of main
	// your code
	LOG4CPLUS_WARN(LogCp::GetInstance()._logger, LOG4CPLUS_TEXT("test"));
}

Posted 25-Nov-16 1:02am

KarstenK

Comments

TimGallin 27-Nov-16 22:07pm

It doesn't work,I have to call doConfigure() function again in main(),in Getinstance() function,I return a static object vLogCp,its lifetime should be the whole process,and the static member variable of vLogCp has be initialed in the constructor func,which include the doConfigure() already,so why I still have to call the doConfigure agian in main()?
Following is my config text:
log4cplus.appender.R=log4cplus::RollingFileAppender
log4cplus.appender.R.File=output_${ENV_VAR}.log
log4cplus.appender.R.MaxFileSize=500KB
log4cplus.appender.R.MaxBackupIndex=5
log4cplus.appender.R.layout=log4cplus::TTCCLayout

log4cplus.rootLogger=INFO, R
log4cplus.logger.test.a.b.c=WARN
log4cplus.logger.filelogger=WARN, R
log4cplus.additivity.filelogger=FALSE