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how to use slf4j in java agent when in spring boot

Springboot uses JarLauncher so that a nested jar is supported.
But the agent code do not load class by using JarLauncher because it executes before the main method.As a result, the console will print
SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
--update
This issue can reproduce the problem.
https://github.com/libinglong/skywalking-threadpool-agent/issues/2

SLF4J Defaulting to Log4j over logback even when binding doesn't exist

I am trying to get SLF4J to bind to logback, but it is instead defaulting to Log4j.
I have all the default config files configured for logback, as well as the bindings.
My classpath has the following relevant jars:
logback-classic
commons-logging (99.0-does-not-exist) //empty jar to exclude commons-logging
logback-core
logback-ext-spring
Note: No log4j dependencies are present.
This is a spring mvc app.
On startup SLF4J has the following output:
SLF4J: Class path contains multiple SLF4J bindings.
SLF4J: Found binding in [jar:file:/C:/Users/masierp/Documents/springsource/vfabric-tc-server-developer-2.8.2.RELEASE/blablahbkla/wtpwebapps/ilm-engine/WEB-INF/lib/activemq-all-5.7.0.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/C:/Users/masierp/Documents/springsource/vfabric-tc-server-developer-2.8.2.RELEASE/blablahbkla/wtpwebapps/ilm-engine/WEB-INF/lib/logback-classic-1.1.2.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]
Note that none of the found bindings are log4j bindings.
I have messed with spring-ext (trying to use it as the spring listener) but with or without this jar the problem persists.
Any help appreciated, thanks.

Probably one of your dependencies has a log4j dependency. You need to exclude it.
Try to look on the parent pom.

The Java Wiki Bot Framework logging

I am using The Java Wiki Bot Framework to do changes in a mediawiki website using java, and it works fine. The only problem is that the JWBF produces a a huge volume of debugging information in the console of my application that is overshadowing my output and make it hard to find, visually. is their anyway that I could stop the logging for JWBF? BTW, JWBF uses SL4J for logging.

This is a slf4j related topic. If no logger binding is defined, you see the following
SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.
If you add a binding e.g. Logback, you can reduce logging output. Your logback.xml should contains a line like
...
<logger name="net.sourceforge.jwbf" level="ERROR"/>
...
For more details see Logback configuration

Does slf4j use commons-logging implementation by default?

I have only worked with log4j in the past. Now I am scouting a new project and noticing that it uses slf4j 1.7.2. I understand it is only an API specification which provides a simplified interface (AKA facade) to various implementations that conform to it, such as java.util.logging, log4j and logback. However, I noticed that commons-logging wasn't mentioned in the list on the API web site, however, its jar was in this app's classpath. When I removed it from the classpath to check whether it was the used implemetation, I confirmed that it indeed was:
SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/commons/logging/LogFactory
Is commons-logging indeed the default implementation for slf4j? Because their documentation says:
If no binding is found on the class path, then SLF4J will default to a no-operation implementation.
at the above linked page. And even though I have slf4j-nop-1.7.2.jar in the classpath, which I am guessing the default implementation referred to above is, I still get the exception asking for org/apache/commons/logging/LogFactory if the commons is not in the classpath, so I am confused.
A clarification would be appreciated.

You need a combination of the binding jar AND the logging implementation (JCL in this case) on the classpath.
Binding with a logging framework at deployment time
commons-logging is not the default, but if you have slf4j-jcl-1.7.2.jar on your classpath, it will try to use that. So if you therefore remove JCL from your path, it will complain that it can't find the classes.
slf4j-nop-1.7.2.jar is the no-op "SLF4J bindings" jar, not an implementation in itself.

Xuggler generates error message

I was working on creating my first Xuggler media application. I was coding by watching their video on how to create the first media application.
Code
package demo;
import com.xuggle.xuggler.IContainer;
public class GetContainerInfo {
public static void main(String[] args) {
if(args.length!=1){
throw new IllegalArgumentException("no file");
}
IContainer container = IContainer.make();
if(container.open(args[0],IContainer.Type.READ,null)<0){
throw new IllegalArgumentException("could not open");
}
}
}
Error
SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.
Do I have the dependencies?
Yes, I do! I have all the dependencies. I imported them while creating the project.
Image:
What is causing that error and how do I solve it?

From SLF4J manual:
> SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
> SLF4J: Defaulting to no-operation (NOP) logger implementation SLF4J:
> See http://www.slf4j.org/codes.html#StaticLoggerBinder for further
> details.
This warning is printed because no slf4j binding could be found on
your class path. The warning will disappear as soon as you add a
binding to your class path. Assuming you add slf4j-simple-1.7.2.jar so
that your class path contains: slf4j-api-1.7.2.jar
slf4j-simple-1.7.2.jar ...

Cause Could be un-availability of dependency jars or version conflicts.
Adding the following jars in the class path worked fine for me:
xuggle-xuggler-5.4.jar
slf4j-api-1.6.4.jar
logback-core-1.0.0.jar
logback-classic-1.0.0.jar