[FELIX-5107] NullPointerException in org.apache.felix.eventadmin.impl.adapter.LogEventAdapter if log msg is empty

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: eventadmin-1.4.4
• Fix Version/s: eventadmin-1.4.6
• Component/s: Event Admin
• Labels: event karaf
• Flags: Patch
• Assignee: David Bosschaert
• Reporter: Torsten Mielke
• Created: 18/Nov/15 09:11
• Updated: 25/May/16 15:09
• Resolved: 18/Nov/15 12:34

Description

If a log event contains an empty message, it raises an NPE in
https://github.com/apache/felix/blob/trunk/eventadmin/impl/src/main/java/org/apache/felix/eventadmin/impl/adapter/LogEventAdapter.java#L180

As a result the Karaf container will raise

'org.apache.felix.eventadmin.impl.adapter.LogEventAdapter$1@XXXXXX' is removed as a LogListener, since it threw an exception.

to stderr and remove this event admin instance.

An empty log message may sound like a stupid thing to do but may happen as a result of e.g. running a Camel route like this one deployed in a Karaf container:

public class LogExceptionRoute extends RouteBuilder {
	
    @Override
	public void configure() {
		onException(Throwable.class)
		    .handled(true)
		    .log(LoggingLevel.ERROR, "${exception.message}");
		from("jetty:http://0.0.0.0:8005")
		.throwException(new Exception()); 
	}	
}

The route raises an empty exception (i.e. no detail message) which then get logged in the onException() policy, causing the error above.