If you attempt to set up WildFly Domain monitoring, and follow the steps as described in the template README page, then your Zabbix Java Gateway stops logging information.

After you copy the WildFly "jboss-client.jar" file to the "/usr/share/zabbix-java-gateway/lib" directory (Step 2 in https://www.zabbix.com/integrations/wildfly#wildfly_domain_jmx), and restart the Zabbix Java Gateway service, then the ZJG service stops logging in it's logfile.

When you check Zabbix-Java-Gateway status after copying the "jboss-client.jar" file, you notice these errors:

Mar 05 21:08:57 zabbix zabbix_java_gateway_startup[2652607]: SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
Mar 05 21:08:57 zabbix zabbix_java_gateway_startup[2652607]: SLF4J: Defaulting to no-operation (NOP) logger implementation
Mar 05 21:08:57 zabbix zabbix_java_gateway_startup[2652607]: SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.

Tested and reproduced on 6.0.39 and 7.2.4.