Bug#1118950: SLF4J: Class path contains multiple SLF4J bindings.

[Fab Stz]

Package: libslf4j-java
Version: 1.7.32-2
Severity: normal

Dear Maintainer,

When launching a program, I have this error reported by SLF4J.

SLF4J: Class path contains multiple SLF4J bindings.
SLF4J: Found binding in [jar:file:/usr/share/java/slf4j-log4j12-1.7.32.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/usr/share/java/slf4j-log4j12.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 [org.slf4j.impl.Log4jLoggerFactory]

I don't really understand where that might come from. In the classpath, there is only one of the two jars that are mentioned.

Full log:

$ DEBUG_WRAPPER=1 vnu-server
[debug] /usr/bin/vnu-server: Found JAVA_HOME = '/usr/lib/jvm/default-java'
[debug] /usr/bin/vnu-server: Found JAVA_CMD = '/usr/lib/jvm/default-java/bin/java'
[debug] /usr/bin/vnu-server: Path to vnu.jar: /usr/share/java
[debug] /usr/bin/vnu-server: Environment variable CLASSPATH is ''
[debug] /usr/bin/vnu-server: Runnning /usr/lib/jvm/default-java/bin/java  -classpath /usr/share/java/css-validator.jar:/usr/share/java/commons-codec.jar:/usr/share/java/commons-fileupload.jar:/usr/share/java/commons-io.jar:/usr/share/java/commons-logging.jar:/usr/share/java/httpclient.jar:/usr/share/java/httpcore.jar:/usr/share/java/icu4j.jar:/usr/share/java/isorelax.jar:/usr/share/java/javax.json.jar:/usr/share/java/javax.json-api.jar:/usr/share/java/log4j-1.2.jar:/usr/share/java/salvation.jar:/usr/share/java/saxon.jar:/usr/share/java/saxonb.jar:/usr/share/java/servlet-api.jar:/usr/share/java/slf4j-api.jar:/usr/share/java/slf4j-log4j12.jar:/usr/share/java/xalan2.jar:/usr/share/java/htmlparser.jar:/usr/share/java/jetty9-http.jar:/usr/share/java/jetty9-io.jar:/usr/share/java/jetty9-security.jar:/usr/share/java/jetty9-server.jar:/usr/share/java/jetty9-servlet.jar:/usr/share/java/jetty9-servlets.jar:/usr/share/java/jetty9-util-ajax.jar:/usr/share/java/jetty9-util.jar:/usr/share/vnu/galimatias.jar:/usr/share/vnu/langdetect.jar:/usr/share/vnu/jing.jar:/usr/share/java/vnu.jar nu.validator.servlet.Main 8888
SLF4J: Class path contains multiple SLF4J bindings.
SLF4J: Found binding in [jar:file:/usr/share/java/slf4j-log4j12-1.7.32.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/usr/share/java/slf4j-log4j12.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 [org.slf4j.impl.Log4jLoggerFactory]
nu.validator.servlet.VerifierServletTransaction - Starting static initializer.
nu.validator.servlet.VerifierServletTransaction - Reading miscellaneous properties.
nu.validator.servlet.VerifierServletTransaction - Starting to loop over config file lines.
nu.validator.servlet.VerifierServletTransaction - Finished reading config.
nu.validator.servlet.VerifierServletTransaction - Converted config to arrays.
nu.validator.servlet.VerifierServletTransaction - Prepared namespace array.
nu.validator.servlet.VerifierServletTransaction - Parsed doctype numbers into ints.
nu.validator.servlet.VerifierServletTransaction - The cache path prefix is: null
nu.validator.servlet.VerifierServletTransaction - Parsing set up. Starting to read schemas.
nu.validator.servlet.VerifierServletTransaction - Will load schema: http://s.validator.nu/html5.rnc
nu.validator.servlet.VerifierServletTransaction - Will load schema: http://s.validator.nu/html5-all.rnc
nu.validator.servlet.VerifierServletTransaction - Will load schema: http://s.validator.nu/xhtml5.rnc
nu.validator.servlet.VerifierServletTransaction - Will load schema: http://s.validator.nu/xhtml5-all.rnc
nu.validator.servlet.VerifierServletTransaction - Will load schema: http://s.validator.nu/svg-xhtml5-rdf-mathml.rnc
nu.validator.servlet.VerifierServletTransaction - Schemas read.
nu.validator.servlet.VerifierServletTransaction - Reading spec.
nu.validator.servlet.VerifierServletTransaction - Spec read.
nu.validator.servlet.VerifierServletTransaction - Reading filter file resources/message-filters.txt
nu.validator.servlet.VerifierServletTransaction - Filter file read.

WARNING: Future checker releases will bind by default to 127.0.0.1.
Your checker deployment might become unreachable unless you use the
nu.validator.servlet.bind-address system property or --bind-address
script option to bind the checker to a different address:

  python ./checker.py --bind-address 192.168.0.10 run
  java -Dnu.validator.servlet.bind-address=192.168.0.10 -cp vnu.jar nu.validator.servlet.Main 8888
  vnu-runtime-image/bin/java -Dnu.validator.servlet.bind-address=192.168.0.10 nu.validator.servlet.Main 8888
  vnu-runtime-image\bin\java.exe -Dnu.validator.servlet.bind-address=192.168.0.10 nu.validator.servlet.Main 8888

Checker service started at http://0.0.0.0:8888/


-- System Information:
Debian Release: 12.12
  APT prefers oldstable-updates
  APT policy: (991, 'oldstable-updates'), (991, 'oldstable-security'), (991, 'oldstable'), (990, 'oldstable-proposed-updates'), (390, 'oldoldstable-security'), (390, 'oldoldstable'), (389, 'oldoldstable-updates'), (380, 'oldoldstable'), (95, 'testing'), (94, 'unstable'), (93, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 6.1.0-40-amd64 (SMP w/4 CPU threads; PREEMPT)
Kernel taint flags: TAINT_PROPRIETARY_MODULE, TAINT_WARN, TAINT_OOT_MODULE
Locale: LANG=fr_FR.UTF-8, LC_CTYPE=fr_FR.UTF-8 (charmap=UTF-8), LANGUAGE=fr:en_US
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

libslf4j-java depends on no packages.

libslf4j-java recommends no packages.

Versions of packages libslf4j-java suggests:
ii  libcommons-logging-java  1.2-3
ii  liblog4j1.2-java         1.2.17-11