Ok, so that ref to ServiceLoader really helped, and I figured my issue looks like https://github.com/spring-projects/spring-boot/issues/32182 So thanks for the tip! From: Nigel L Jones <jonesn@uk.ibm.com> Date: Thursday, 1 September 2022 at 14:49 To: logback users list <logback-user@qos.ch> Subject: Re: [EXTERNAL] Re: [logback-user] Logback 1.3.0/1.4.0 : slf4j-api & StaticLoggerBinder Thanks, I did try 1.3 with the same results. Mostly Jakarta, but some javax via transitive dependencies. The server applications use spring (springboot 2.7.3/spring 5.3.22), so that may be the area to persue as spring introduces it’s own classloader and may cause problems with ServiceLoader?? –via the spring community so thanks for the pointer. From: logback-user <logback-user-bounces@qos.ch> on behalf of Raymond Augé <raymond.auge@liferay.com> Date: Thursday, 1 September 2022 at 14:15 To: logback users list <logback-user@qos.ch> Subject: [EXTERNAL] Re: [logback-user] Logback 1.3.0/1.4.0 : slf4j-api & StaticLoggerBinder Hi Nigel, You probably want logback 1. 3 (1. 4 is for Jakarta EE as opposed to 1. 3 being for Java EE). Secondly, logback now uses ServiceLoader to find "providers" so make sure any adjustments are made to your classloading such that ZjQcmQRYFpfptBannerStart This Message Is From an External Sender This message came from outside your organization. ZjQcmQRYFpfptBannerEnd Hi Nigel, You probably want logback 1.3 (1.4 is for Jakarta EE as opposed to 1.3 being for Java EE). Secondly, logback now uses ServiceLoader to find "providers" so make sure any adjustments are made to your classloading such that that can work. Cheers On Thu, Sep 1, 2022 at 7:59 AM Nigel L Jones <jonesn@uk.ibm.com<mailto:jonesn@uk.ibm.com>> wrote: Hi, I’m a maintainer on the open source Egeria project https://github.com/odpi/egeria<https://github.com/odpi/egeria>. We typically use slf4j in our Java 11 code, and depend on slf4j-api. Then in any ‘applications’ (a client tool, or a server) we include an implementation for logging, such as logback – specifically logback-classic We regularly update our dependencies and today I tried upgrading from logback 1.2.11 to 1.4.0. On doing so I see we now fail to startup, as slf4j is unable to find a logging implementation. Slf4j is at 2.0.0. We get an exception Caused by: java.lang.NoClassDefFoundError: org/slf4j/impl/StaticLoggerBinder Whilst this is an slf4j config issue in most regards, I wonder if the new logback version is not keeping slf4j happy with its implementation in some way I opened up an issue in our own bug tracker at https://github.com/odpi/egeria/issues/6884<https://github.com/odpi/egeria/issues/6884> which has the dependency tree & stack trace in full. Is there a change in the new version that’s caught us out? Any indications from the log? (If it is a logback issue happy to open up a bug report, but now knowing logback well figured I’d ask here first!) Many thanks Nigel Jones Unless otherwise stated above: IBM United Kingdom Limited Registered in England and Wales with number 741598 Registered office: PO Box 41, North Harbour, Portsmouth, Hants. PO6 3AU _______________________________________________ logback-user mailing list logback-user@qos.ch<mailto:logback-user@qos.ch> http://mailman.qos.ch/mailman/listinfo/logback-user<http://mailman.qos.ch/mailman/listinfo/logback-user> -- Raymond Augé (@rotty3000) Senior Software Architect Liferay, Inc. (@Liferay) OSGi Fellow, Java Champion Unless otherwise stated above: IBM United Kingdom Limited Registered in England and Wales with number 741598 Registered office: PO Box 41, North Harbour, Portsmouth, Hants. PO6 3AU