slf4j logback substituteLogger

Question

I'm not able anymore to start my loggers using the gradle task `jettyRuǹ . The 1st issue with multiple bindings wasn't a problem. But now (after the upgrade to gradle 1.4, I guess) my loggers don't start. The slf4j doc says to reset the context programmatically, but I would prefer to do it by configuration as jettyRun is only used for development.

$ gradle jettyRun
:compileJava UP-TO-DATE
:processResources UP-TO-DATE
:classes UP-TO-DATE
:jettyRun
SLF4J: Class path contains multiple SLF4J bindings.
SLF4J: Found binding in [jar:file:/opt/gradle-1.4/lib/logback-classic-1.0.9.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/home/bertrand/.gradle/caches/artifacts-23/filestore/ch.qos.logback/logback-classic/1.0.9/jar/258c3d8f956e7c8723f13fdea6b81e3d74201f68/logback-classic-1.0.9.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: See http://www.slf4j.org/codes.html#multiple_bindings for an explanation.
SLF4J: Actual binding is of type [ch.qos.logback.classic.util.ContextSelectorStaticBinder]
SLF4J: The following loggers will not work because they were created
SLF4J: during the default configuration phase of the underlying logging system.
SLF4J: See also http://www.slf4j.org/codes.html#substituteLogger
SLF4J: org.yajug.users.api.MembershipController
SLF4J: org.yajug.users.json.Serializer
SLF4J: org.yajug.users.api.MemberController
SLF4J: org.yajug.users.service.MemberServiceImpl
SLF4J: org.yajug.users.persistence.MongoConnector

Answer 1

Finally I found what was wrong:

• The logging context is initialized lazily, at the first call to a logger.
• In the context of my web app (a single page web app that do only async calls), the first page was calling 2 async requests
• each request had a logger and the initialization was made concurrently, it's the reason why some of my loggers implementation where substituted by a nop impl.
• by adding a logger call on the app startup, the context is initialized correctly