Send/redirect/route java.util.logging.Logger (JUL) to Logback using SLF4J?
Is it possible to have a typical call to java.util.logging.Logger
and have it route to Logback using SLF4J? This would be nice since I wouldn't have to refactor the old jul code line by line.
EG, say we have this line:
private static Logger logger = Logger.getLogger(MahClass.class.getName());
//...
logger.info("blah blah blah");
It would be nice to configure this to call through SLF4J.
It's very easy and not a performance issue anymore.
There are two ways documented in the SLF4J manual. There are also precise examples in the Javadocs
Add jul-to-slf4j.jar to your classpath. Or through maven dependency:
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>jul-to-slf4j</artifactId>
<version>1.7.0</version>
</dependency>
If you don't have logging.properties (for java.util.logging), add this to your bootstrap code:
SLF4JBridgeHandler.removeHandlersForRootLogger();
SLF4JBridgeHandler.install();
If you have logging.properties (and want to keep it), add this to it:
handlers = org.slf4j.bridge.SLF4JBridgeHandler
In order to avoid performance penalty, add this contextListener to logback.xml (as of logback version 0.9.25):
<?xml version="1.0" encoding="UTF-8"?>
<configuration>
<contextListener class="ch.qos.logback.classic.jul.LevelChangePropagator">
<!-- reset all previous level configurations of all j.u.l. loggers -->
<resetJUL>true</resetJUL>
</contextListener>
...
</configuration>