Writing log messages in Sametime 7.5 plugins

Unfortunately the Sametime 7.5 SDK doesn’t contain any information that I can find on how to use log and debug messages in custom plugins. Furthermore all the Sametime 7.5 articles on developerWorks I have seen use System.out which is really a no, no. This post contain some information on logging that I have found out myself – partly through looking around in the Sametime 7.5 Connect client installation and partly by trial-and-error.

FYI: I’m doing a fair bit of Sametime 7.5 plugin development at the moment. For one because it’s fun and second because I’m writing an article for THE VIEW (slated for the March/April issue) on Sametime 7.5 development.


Logging is at the heart of any development project whether that be a Notes database or a Java application. You can of cause resort to using System.out / System.err for logging but that’s clearly a no, no! If you are in doubt why I suggest you start here. Once you come to the conclusion that you really should be using a logging framework there basically is two options:

  • java.util.logging (available directly in the JDK since JDK 1.4)
  • Apache log4j

Many libraries will furthermore use Jakarta Commons Logging to isolate themselves from the underlying logging technology. In part because they cannot tell which logging framework will be used by clients and because it affords the client the choice.

However in the case of the Sametime 7.5 Connect client the choice has been made for you since Sametime 7.5 uses java.util.logging. You can choose to use Commons Logging but then the logging levels will not fit the ones used in Sametime.

I would suggest you stay with java.util.logging.

Please note: The way logging works while developing plugins in Eclipse is very much different from how it works in the *real* client. When developing all logging, incl. System.out, goes to the console.

Using java.util.logging

Obtaining a java.util.logging.Logger instance is easy:

Logger log = Logger.getLogger(this.getClass().getName());

I suggest you follow the above example and use the class name as the logger name which is also a best practice and the way that IBM does it.

Once you have the Logger-instance you can use it to log information using the different logging Levels (see the Javadoc for more information on java.util.logging).

Configuring logging in Sametime 7.5

The logs written are placed in the Sametime-directory under your using profile hereafter called the log-directory. On my Windows laptop this is “C:Documents and Settingslekkim.HQApplication DataSametime”. The logging itself is configured from the sametime.properties file in the Sametime 7.5 Connect client directory (again on my Windows laptop this is “C:Program FilesIBMSametime 7.5”).

The top of my default sametime.properties looks like this:

## G11N DNT
## Logging properties

## app properties

By default log-messages goes to sametime.log.0 in the log-directory with the maximum level of INFO (top bold line). To diagnose issues increase the log level to FINE, FINER, ALL etc. Be aware that the finer levels will produce *lots* of output. Note that messages written to System.out is directed to System.err by default (the second line in bold). To get this information change the redirectSystemOutput to false.

Doing this will cause output to be written to sametime.log in the log-directory instead. Restarting the Sametime 7.5 client while redirectSystemOutput is false will rotate the previous sametime.log to sametime.log.previous.

The nitty-gritty details

It appears that most of the java.util.logging configuration is done through the rcpinstall.properties file in /plugins/com.ibm.rcp.base_6.1.0.0-20060714/config/muservice. Although I wouldn’t suggest changing the file itself it may be beneficially to peruse the file to see how it’s done.

If you really want to know that is… 😉


It appears that Sametime uses java.util.logging and that is is quite straight forward to use – once you know how… Logging levels are easily controlled from sametime.properties and extending the logging framework to do central logging should be easily accomplished.

Happy logging…

4 thoughts on “Writing log messages in Sametime 7.5 plugins”

  1. “Obtaining a java.util.logger.Logger instance is easy:”

    should read

    “Obtaining a java.util.logging.Logger instance is easy:”


  2. Hi,

    I want a details of FINE,FINER,FINEST,INFO levels. I am getting confusion where i have to use those levels all are looking same. Can you guide me in this.


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