Listening to status messages

You may also attach a StatusListener to a StatusManager so that you can take immediate action in response to status messages, especially to messages occurring after logback configuration. Registering a status listener is a convenient way to supervise logback's internal state without human intervention.

Logback ships with a StatusListener implementation called OnConsoleStatusListener which, as its name indicates, prints all new incoming status messages on the console.

Here is sample code to register an OnConsoleStatusListener instance with the StatusManager.

   LoggerContext lc = (LoggerContext) LoggerFactory.getILoggerFactory(); 
   StatusManager statusManager = lc.getStatusManager();
   OnConsoleStatusListener onConsoleListener = new OnConsoleStatusListener();
   statusManager.add(onConsoleListener);

Note that the registered status listener will only receive status events subsequent to its registration. It will not receive prior messages. Thus, it is usually a good idea to place status listener registration directives at top of the configuration file before other directives.

It is also possible to register one or more status listeners within a configuration file. Here is an example.

Example: Registering a status listener (logback-examples/src/main/resources/chapters/configuration/onConsoleStatusListener.xml)

<configuration>
  <statusListener class="ch.qos.logback.core.status.OnConsoleStatusListener" />  

  ... the rest of the configuration file  
</configuration>