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print format in apache commons logging

Using log4j underneath.
How can I do, format or wildcard stuff like:
System.out.printf('%s', 5)
With
log.info('%s', 5) //org.apache.commons.logging.Log instance
Version:commons-logging-1.1.3.jar.
The bad thingy about this mentioned API is:
It has methods info(object) and info(object, throwable) only.
Or logging did not evolve there??

This is probably the easiest way to do it
log.info(String.format("%s", 5));

The feature you are looking for is included in log4j2:
http://www.apache.org/dyn/closer.cgi/logging/log4j/2.1/apache-log4j-2.1-bin.zip
You have to include at least two jar files:
log4j-api-2.1.jar
log4j-core-2.1.jar
Finally put a configuration file named "log4j2.xml" in your classpath which can look like this:
<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="WARN">
<Appenders>
<Console name="Console" target="SYSTEM_OUT">
<PatternLayout pattern="%d{HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n"/>
</Console>
</Appenders>
<Loggers>
<Root level="info">
<AppenderRef ref="Console"/>
</Root>
</Loggers>
</Configuration>
After the configuration you should be able to achieve what you want with the following code:
Logger log = LogManager.getLogger(YOURCLASSNAME.class);
log.printf(Level.INFO,"%s",5);

Yes, it is achievable in "slf4j". Try using the below snapshots-
log.info("My name is %s %s",firstName,secondName)
or
LOG.debug("WidgetName:{}\n curWidgetVOArray=\n",curWidgetName, curWidgetVOArray);
Refer - http://javarevisited.blogspot.in/2013/08/why-use-sl4j-over-log4j-for-logging-in.html

Log4j2 does not write logs to a file

I am using log4j2 with slf4j and I want to write my logs to a file. This is my log4j2.xml configuration file:
<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="WARN">
<Appenders>
<Console name="Console" target="SYSTEM_OUT">
<PatternLayout pattern="%d{HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n" />
</Console>
<RandomAccessFileAppender name="Logfile"
fileName="\\domain\path\logs\log.txt">
<PatternLayout pattern="%d{HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n" />
</RandomAccessFileAppender>
</Appenders>
<Loggers>
<Root level="info">
<AppenderRef ref="Logfile" />
<AppenderRef ref="Console" />
</Root>
</Loggers>
</Configuration>
Logging to the console works, but I do not get any logs in the file. I get the following error message on the console:
2014-05-28 10:17:01,164 ERROR Error processing element RandomAccessFileAppender: CLASS_NOT_FOUND
2014-05-28 10:17:01,309 ERROR Unable to locate appender Logfile for logger
Why does log4j not find the class? Do I have to use additional dependencies?

date variable not resolve in log4j2.xml when using log4j 2.0 in standalone java app under osx

I'm using log4j 2 in my standalone java app. However, I'm struggling with the date variable in the log4j2.xml configuration. It's not getting resolved.
Here is my log4j2.xml configuration file:
<?xml version="1.0" encoding="UTF-8"?>
<configuration status="OFF">
<appenders>
<Console name="Console" target="SYSTEM_OUT">
<PatternLayout pattern="%d [%t] %-5level %logger{36} - %msg%n"/>
</Console>
<File name="File" fileName="logs/Server-${date}.log">
<PatternLayout pattern="%d [%t] %-5level %logger{36} - %msg%n"/>
</File>
</appenders>
<loggers>
<root level="all">
<appender-ref ref="Console"/>
<appender-ref ref="File"/>
</root>
</loggers>
</configuration>
However, the log file that gets created is: Server-${date}.log
My app runs under OSX, not sure that is the cause.
Thanks guys.

From the Property Substitution chapter in the Log4j2 Configuration Page
date: Inserts the current date and/or time using the specified format
So you just have to add a date format to your property.
... <File name="File" fileName="logs/Server-${date:yyyy-MM-dd}.log"> ...
The name of your file would be Server-2014-05-06.log.
You can visit the SimpleDateFormat class from the Java Api to see all formatting possibilities.

log4j2.xml is not loading in eclipse

I'm fairly new to log4j. Trying to use log4j2.xml to configure. I added the file to the build path and it worked once, but is no longer working.
This is my log4j2.xml:
<?xml version="1.0" encoding="UTF-8"?>
<configuration>
<appenders>
<Console name="Console" target="SYSTEM_OUT">
<PatternLayout pattern="%d{HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n"/>
</Console>
</appenders>
<loggers>
<root level="TRACE">
<appender-ref ref="Console"/>
</root>
</loggers>
</configuration>
I stripped it down, just to test it to get it working. I checked debug, and the logger config is using Default.
I also tried naming the file log4j2-test.xml.
Any ideas?
Thanks

Since you uses "servlets" as the tag, I assume you are working in a web application. You need to place your log4j.xml into a location that your web application classloader can find. For example, the WEB-INF/classes directory.

Disabling Log4J Output in Java

How can one quickly turn off all Log4J output using a log4j.properties file?

Set level to OFF
(instead of DEBUG, INFO, ....)

If you want to turn off logging programmatically then use
List<Logger> loggers = Collections.<Logger>list(LogManager.getCurrentLoggers());
loggers.add(LogManager.getRootLogger());
for ( Logger logger : loggers ) {
logger.setLevel(Level.OFF);
}

log4j.rootLogger=OFF

You can change the level to OFF which should get rid of all logging. According to the log4j website, valid levels in order of importance are TRACE, DEBUG, INFO, WARN, ERROR, FATAL. There is one undocumented level called OFF which is a higher level than FATAL, and turns off all logging.
You can also create an extra root logger to log nothing (level OFF), so that you can switch root loggers easily. Here's a post to get you started on that.
You might also want to read the Log4J FAQ, because I think turning off all logging may not help. It will certainly not speed up your app that much, because logging code is executed anyway, up to the point where log4j decides that it doesn't need to log this entry.

In addition, it is also possible to turn logging off programmatically:
Logger.getRootLogger().setLevel(Level.OFF);
Or
Logger.getRootLogger().removeAllAppenders();
Logger.getRootLogger().addAppender(new NullAppender());
These use imports:
import org.apache.log4j.Logger;
import org.apache.log4j.Level;
import org.apache.log4j.NullAppender;

Change level to what you want. (I am using Log4j2, version 2.6.2). This is simplest way, change to <Root level="off">
For example: File log4j2.xml
Development environment
<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="WARN">
<Appenders>
<Console name="Console" target="SYSTEM_OUT">
<PatternLayout pattern="%d{HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n"/>
</Console>
<Console name="SimpleConsole" target="SYSTEM_OUT">
<PatternLayout pattern="%msg%n"/>
</Console>
</Appenders>
<Loggers>
<Root level="error">
<AppenderRef ref="Console"/>
</Root>
</Loggers>
<Loggers>
<Root level="info">
<AppenderRef ref="SimpleConsole"/>
</Root>
</Loggers>
</Configuration>
Production environment
<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="WARN">
<Appenders>
<Console name="Console" target="SYSTEM_OUT">
<PatternLayout pattern="%d{HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n"/>
</Console>
<Console name="SimpleConsole" target="SYSTEM_OUT">
<PatternLayout pattern="%msg%n"/>
</Console>
</Appenders>
<Loggers>
<Root level="off">
<AppenderRef ref="Console"/>
</Root>
</Loggers>
<Loggers>
<Root level="off">
<AppenderRef ref="SimpleConsole"/>
</Root>
</Loggers>
</Configuration>