MDC in SLF4J not supported?

[wiradikusuma]

Hi guys, I'm using SLF4J but got stuck in MDC.

...
MDC.put("identifier", profile.getIdentifier());
...

[2009-02-06 00:09:31.896] server-tomcat-thread-2   ringsource.server.catalina].[localhost].[/].[dispatcher].unknown E Servlet.service() for servlet dispatcher threw exception
java.lang.NoClassDefFoundError: org/slf4j/impl/StaticMDCBinder
	at org.slf4j.MDC.<clinit>(MDC.java:69)
	at com.foo.core.service.impl.DefaultHttpRequestProcessor.processInternal(DefaultHttpRequestProcessor.java:48)
	at com.foo.core.service.impl.DefaultHttpRequestProcessor.process(DefaultHttpRequestProcessor.java:44)
	at com.foo.core.model.HttpProfile.receive(HttpProfile.java:110)
	at com.foo.web.action.HttpEndpoint.handleRequestInternal(HttpEndpoint.java:35)
	at org.springframework.web.servlet.mvc.AbstractController.handleRequest(AbstractController.java:153)
	at org.springframework.web.servlet.mvc.SimpleControllerHandlerAdapter.handle(SimpleControllerHandlerAdapter.java:48)
	at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:875)
	at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:807)
	at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:571)
	at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:501)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:690)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
	at org.apache.catalina.valves.CometConnectionManagerValve.invoke(CometConnectionManagerValve.java:248)
	at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:568)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
	at com.springsource.server.servlet.tomcat.internal.ApplicationNameTrackingValve.invoke(ApplicationNameTrackingValve.java:74)
	at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:568)

Manifest-Version: 1.0
Bundle-ManifestVersion: 2
Bundle-Name: foo - core internal
Bundle-SymbolicName: com.foo.core.internal
Bundle-Version: 1.0.0.SNAPSHOT
Import-Library: org.springframework.spring;version="[2.5,2.6)"
Import-Bundle: com.springsource.org.eclipse.persistence;version="[1.0.0,1.1.0)";import-scope:=application,
 com.springsource.org.eclipse.persistence.jpa;version="[1.0.0,1.1.0)",
 com.springsource.javax.persistence;version="[1.0.0,1.0.0]",
 com.springsource.org.aspectj.runtime;version="1.6.0",
 com.springsource.org.aspectj.weaver;version="1.6.0",
 com.springsource.org.joda.time;version="1.5",
 com.springsource.org.quartz;version="1.6"
Import-Package: com.foo.core.model,
 com.foo.core.service,
 com.foo.infrastructure,
 javax.annotation,
 javax.sql,
 org.apache.commons.logging,
 org.slf4j;version="1.5",
 org.slf4j.helpers;version="1.5",
 org.slf4j.impl;version="1.5",
 org.slf4j.spi;version="1.5"

I've tried importing only org.slf4j and org.slf4j with org.slf4j.impl, still no luck. Any suggestion?

[KnisterPeter]

We have the same problem here. Is there any solution to this?

[oleg.zhurakousky]

SLF4J and Log4J are part of the dmServer core and as you can see these bundles are deployed in the lib directory.

The bundle in question is com.springsource.slf4j.simple which I supposed you've installed but probably in the wrong place. This is the bundle that has org.slf4j.impl.StaticMDCBinder class, but because it is used by dmServer logging system it must be in the lib directory and not in repository/bundles/usr.

So to make the long story short install com.springsource.slf4j.simple into lib directory of the server and your Import-Package should work:

Import-Package: org.slf4j.impl;version="[1.5.6,1.5.6]",
 . . .

[oleg.zhurakousky]

Hold it (my bad)
Could you please post a version of DMServer you are using?
I just tested it with 1.0.2 and it works fine.
Just as an FYI, the org.slf4j.MDC and org.slf4j.impl.StaticMDCBinder are both loaded by the System bundle and are exported by the com.springsource.slf4j.api-1.5.6.jar bundle located in the lib directory of the server distribution.
Also, looking at it further the NCDF is thrown by SLF4J intentionally (just look at the static initializer of MDC class), and the code points to the following link:
http://www.slf4j.org/codes.html#no_static_mdc_binder
It seems like in your configuration it can not fine the appropriate binding, where in my case it defaults to org.slf4j.helpers.NOPMakerAdapter which is also loaded by the system bundle and is found in com.springsource.slf4j.api-1.5.6.jar. So you might still be missing com.springsource.slf4j.simple, or any other binding. . .

[KnisterPeter]

We deployed logback as dependency (inside our war) to our application. This caused the error. After removing any slf4j impl and api from our war it does work. Thanks for you help.

[KnisterPeter]

To give a bit more insides (I hope this is correct):

There is no slf4j implementation in the lib directory. (Only the slf4j api and the log4j and commons-logging bindings which delegate to slf4j).
If you then use slf4j with MDC but do not supply a MDC aware implementation in the lib directory this binding could not be found. Right?

[oleg.zhurakousky]

This would probably be more of a SLF4J question, but according to my understanding of their documentation here: http://www.slf4j.org/codes.html#no_static_mdc_binder it is correct.
Why do you keep JARs in the WEB-INF/lib? Why not use OSGi capabilities and manage dependencies via MANIFEST?

[KnisterPeter]

We are currently evaluating spring-dm as alternative to plain tomcat server, since we have many memory leaks on dependent libraries (e.g. activemq, richfaces) and therefore we currently have not fully migrated to osgi.