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Unable to locate logger configuration in use

I have a jar, say a.jar, for which I'd like to enable logging only at INFO level. This jar also depends on another jar, say b.jar, which uses Apache HTTP client. When I run my application, I see a lot of debug output on the screen including stuff from the Apache HTTP client in this format alone, irrespective of what I put in the log4j.properties:
[com.amazonaws.AmazonWebServiceClient] : Internal logging successfully configured to commons logger: true Ignored FQCN: org.apache.commons.logging.impl.SLF4JLocationAwareLog
For the life of me, I'm unable to figure out where the jars are getting their configuration from. Here're things I tried.
1. Added a log4j.properties to only a.jar's main/resources dir
2. Added a log4j.properties to only b.jar's main/resources dir
3. Removed log4j.properties
Please help me with some inputs as to where the logging configuration may be getting picked up from.
Here're pom extracts of a.jar
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.5</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.15</version>
<scope>compile</scope>
</dependency>
Here's the extract for b.jar
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.7</version>
<scope>compile</scope>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>1.7.7</version>
<scope>compile</scope>
</dependency>

I assume that you mean this “Apache HTTP client”? If so, then your logging configuration for Log4J does not affect the log output of the HttpClient simply because the latter does neither use SLF4J nor Log4J. As you can see from this POM, HttpClient uses Apache Commons Logging for its log output instead.
So your goal is to redirect all Commons Logging output via SLF4J to Log4J. This requires two steps:
Add an SLF4J bridge for Commons Logging.
Make sure that the bridge is used as a replacement for Commons Logging.
The bridge to add is described here. To make sure that the bridge is actually used, I would recommend to exclude the original Commons Logging JAR. You should be able to achieve both steps with the following new/updated dependencies for your project B:
<dependency>
<groupId>org.apache.httpcomponents</groupId>
<artifactId>httpclient</artifactId>
<version>4.5.3</version>
<exclusions>
<exclusion>
<groupId>commons-logging</groupId>
<artifactId>commons-logging</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>jcl-over-slf4j</artifactId>
<version>1.7.24</version>
</dependency>
I have added the jcl-over-slf4j bridge in the latest SLF4J version 1.7.24 since it seems that your version of SLF4J (1.7.7) doesn’t seem to support Commons Logging 1.2, yet, which might be used by the HttpClient (at least by the one in version 4.5.3).
(Note that I haven’t tested this. But the eventual solution should at least be pretty similar to the described approach.)

Looking at this, it seems like one of the amazon sdk jars is the place this logging configuration would be present in.
It uses apache commons logging and any configuration that you are doing in your project is being done for slf4j and hence is not taking any effect.

Difference between slf4j-log4j12 and log4j-over-slf4j

What's the difference between slf4j-log4j12 and log4j-over-slf4j and when should each be used?
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>1.7.12</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>log4j-over-slf4j</artifactId>
<version>1.7.12</version>
</dependency>

log4j-over-slf4j
Use this if your code or some libraries you are using uses Log4j directly, but you want to use a different SLF4J binding than Log4j. It will route the Log4j API calls to SLF4J to the binding you choose. You need to remove the Log4j library from your classpath and replace it with this dependency.
slf4j-log4j12
Use this if you want to use the Log4j 1.2 binding for SLF4J.
You shouldn't use both of these libraries at the same time.
Please note also that Log4j 2 has been released.

Using slf4j logger in a simple mvc Spring web project

I am learning spring web mvc project from online resources, i came across this logger slf4j, and i want to use it in my application.
I don't have any idea on how to add this. what i am thinking is i should remove commons-logging.jar from lib folder, and add another jar file to lib folder, but then i don't know which jar file i should add as there are many jar files present in slf4j.zip that i have downloaded from its official site.
I have searched and read few posts/articles about integrating slf4j but they all were related to maven, and i don't have maven, i simply started working with adding spring framework jars to dynamic web project.
Please tell me how and what files i should add in lib folder for logging purpose. or how to configure the slf4j logger.
thanx folks!!

The official source of information on logging in Spring is the Spring Reference.
If you want to use SLF4J, this document suggests using the following Maven dependencies:
<dependencies>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>4.0.6.RELEASE</version>
<exclusions>
<exclusion>
<groupId>commons-logging</groupId>
<artifactId>commons-logging</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>jcl-over-slf4j</artifactId>
<version>1.5.8</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.5.8</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>1.5.8</version>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.14</version>
</dependency>
</dependencies>
In other words, you need four .jar files, and you need to make sure that the Commons Logging library is NOT on your classpath.
If you do not use Maven, you can download these .jars from the Maven Central Repository manually. Enter groupId, artifactId and version on that page, press Search, and download the .jar file (not sources.jar!). Here are direct links to these .jar files: jcl-over-slf4j, slf4j-api, slf4j-log4j12, log4j.
You will also need to create and put on your classpath the configuration file for log4j (log4j.xml or log4j.properties).
I think that by not using Maven you make your life harder, not easier. It's better to spend some time learning it, than spend a lot of time trying to avoid learning it.

I would actually argue against using pure SLF4J to begin with, because its own creators have already created a successor.
Reasons to use it instead of SLF4J are given on http://logback.qos.ch/reasonsToSwitch.html
And the "First baby steps" in the manual are at http://logback.qos.ch/manual/introduction.html

"This version of SLF4J requires log4j version 1.2.12" warning with log4j 1.2.17

I have a Java Maven project whose dependencies include slf4j and its log4j adapter.
I manage the versions of log4j, slf4j-log4j12 and slf4j-api to its newest versions according to http://mvnrepository.com and especially the log4j version of 1.2.17 is well over 1.2.12 but I still get the error
SLF4J: This version of SLF4J requires log4j version 1.2.12 or later.
See also http://www.slf4j.org/codes.html#log4j_version
which is totally unclear to me.
My Maven dependency management looks like this:
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.apache.jena</groupId>
<artifactId>apache-jena-libs</artifactId>
<type>pom</type>
<version>2.10.0</version>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.17</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>1.7.5</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.5</version>
</dependency>
</dependencies>
</dependencyManagement>
How can I get rid of the warning?
P.S.: I also get a java.lang.NoSuchMethodError: org.apache.log4j.Logger.isTraceEnabled().
P.P.S.: Because of your comments I remembered that the program has a "lib" folder which is not included in the classpath by Maven but by Eclipse itself so the conflicting dependencies must lie there. Sorry, I totally forgot that I guess that's my fault for mixing Maven with a lib folder. I guess I must try to convert as much of the libraries to maven dependencies.
The strange thing though is just that even if I edit "Order and Export" to put the Maven dependencies at the top, the problem still occurs.

StaticLoggerBinder code in slf4j-log4j12 which gets loaded very early on performs a check to determine whether the TRACE level is available in log4j. Here is the code:
private StaticLoggerBinder() {
loggerFactory = new Log4jLoggerFactory();
try {
Level level = Level.TRACE;
} catch (NoSuchFieldError nsfe) {
Util.report("This version of SLF4J requires log4j version 1.2.12 or later."+
" See also http://www.slf4j.org/codes.html#log4j_version");
}
}
It seems pretty airtight to me.
It may be that some other dependency is pulling in or actually embeds an earlier version of log4j. Some *-standalone.jar files are known to do that.
Check your class path at deployment time. Are you deploying in an app server? Is an older version of log4j on the server class path? In a java endorsed path?

You should define the <dependency> outside the <dependencyManagement> as the following: -
<dependencyManagement>
<dependencies>
...
</dependencies>
</dependencyManagement>
<dependencies>
<dependency>
<groupId>org.apache.jena</groupId>
<artifactId>apache-jena-libs</artifactId>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
</dependency>
</dependencies>
Please see Introduction to the Dependency Mechanism: Dependency Management for further information.
I hope this may help.

Changing comment to answer, since it appeared to solve the issue.
This is a classloader problem, maven built it correctly but is missing
for dependencies. Could you try to provide the missing dependencies to
maven? Otherwise I suggest you look in the Eclipse specific
dependencies.

SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder"

My application is to be deployed on both tcServer and WebSphere 6.1. This application uses ehCache and so requires slf4j as a dependency.
As a result I've added the slf4j-api.jar (1.6) jar to my war file bundle.
The application works fine in tcServer except for the following 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.
However, when I deploy in WebSphere I get a java.lang.NoClassDefFoundError: org.slf4j.impl.StaticLoggerBinder.
Also accompanied by Failed to load class "org.slf4j.impl.StaticMDCBinder"
I've checked the classpaths of both application servers and there is no other slf4j jar.
Does anyone have any ideas what may be happening here?

I had the same issue with WebSphere 6.1. As Ceki pointed out, there were tons of jars that WebSphere was using and one of them was pointing to an older version of slf4j.
The No-Op fallback happens only with slf4j -1.6+ so anything older than that will throw an exception and halts your deployment.
There is a documentation in SLf4J site which resolves this. I followed that and added slf4j-simple-1.6.1.jar to my application along with slf4j-api-1.6.1.jar which I already had.
If you use Maven, add the following dependencies, with ${slf4j.version} being the latest version of slf4j
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>${slf4j.version}</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-simple</artifactId>
<version>${slf4j.version}</version>
</dependency>
This solved my issue.

This is for those who came here from google search.
If you use maven just add the following
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.5</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>1.7.5</version>
</dependency>
Or
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.5</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-simple</artifactId>
<version>1.6.4</version>
</dependency>

Simply add this to your pom.xml:
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-simple</artifactId>
<version>1.7.21</version>
</dependency>

Quite a few answers here recommend adding the slf4j-simple dependency to your maven pom file. You might want to check for the most current version.
At https://mvnrepository.com/artifact/org.slf4j/slf4j-simple
you'll find the latest version of the SLF4J Simple Binding. Pick the one that suites you best (still 1.7.32 from 2021-07 is the stable version as of 2021-10) and include it to your pom.xml.
For your convenience some dependencies are shown here - but they might not be up-to-date when you read this!
Alpha Version of 2021-08
<!-- https://mvnrepository.com/artifact/org.slf4j/slf4j-simple -->
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-simple</artifactId>
<version>2.0.0-alpha5</version>
</dependency>
Beta Version of Feb 2019
<!-- https://mvnrepository.com/artifact/org.slf4j/slf4j-simple -->
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-simple</artifactId>
<version>1.8.0-beta4</version>
</dependency>
Stable Version 2021-07
<!-- https://mvnrepository.com/artifact/org.slf4j/slf4j-simple -->
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-simple</artifactId>
<version>1.7.32</version>
</dependency>
I removed the scope test part thanks to the comment below.

You need to add following jar file in your classpath: slf4j-simple-1.6.2.jar. If you don't have it, please download it. Please refer to http://www.slf4j.org/codes.html#multiple_bindings

Sometime we should see the note from the warnin SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details..
This happens when no appropriate SLF4J binding could be found on the class path
You can search the reason why this warning comes.
Adding one of the jar from *slf4j-nop.jar, slf4j-simple.jar, slf4j-log4j12.jar, slf4j-jdk14.jar or logback-classic.jar* to the class path should solve the problem.
compile "org.slf4j:slf4j-simple:1.6.1"
for example add the above code to your build.gradle or the corresponding code to pom.xml for maven project.

I was facing same error. I have configured slf4j-api, slf4j-log4j12 and log4j, in my local development. All configuration was fine, but slf4j-log4j12 dependency which I copied from mvnrepository had test scope <scope>test</scope>. When I removed this every thing is fine.
Some times silly mistakes breaks our head ;)

put file slf4j-log4j12-1.6.4.jar in the classpath will do the trick.

SLF4j is an abstraction for various logging frameworks. Hence apart from having slf4j you need to include any of your logging framework like log4j or logback (etc) in your classpath.
To have an idea refer the First Baby Step in http://logback.qos.ch/manual/introduction.html

If you are using maven to dependency management so you can just add following dependency in pom.xml
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>1.5.6</version>
</dependency>
For non-Maven users
Just download the library and put it into your project classpath.
Here you can see details: http://www.mkyong.com/wicket/java-lang-classnotfoundexception-org-slf4j-impl-staticloggerbinder/

I got into this issue when I get the following 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.
when I was using slf4j-api-1.7.5.jar in my libs.
Inspite I tried with the whole suggested complement jars, like slf4j-log4j12-1.7.5.jar, slf4j-simple-1.7.5 the error message still persisted. The problem finally was solved when I added slf4j-jdk14-1.7.5.jar to the java libs.
Get the whole slf4j package at http://www.slf4j.org/download.html

<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-simple</artifactId>
<version>1.7.21</version>
</dependency>
Put above mentioned dependency in pom.xml file

I was facing the similar problem with Spring-boot-2 applications with Java 9 library.
Adding the following dependency in my pom.xml solved the issue for me:
<dependency>
<groupId>com.googlecode.slf4j-maven-plugin-log</groupId>
<artifactId>slf4j-maven-plugin-log</artifactId>
<version>1.0.0</version>
</dependency>

Slf4j is a facade for the underlying logging frameworks like log4j, logback, java.util.logging.
To connect with underlying frameworks, slf4j uses a binding.
log4j - slf4j-log4j12-1.7.21.jar
java.util.logging - slf4j-jdk14-1.7.21.jar etc
The above error is thrown if the binding jar is missed. You can download this jar and add it to classpath.
For maven dependency,
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>1.7.21</version>
</dependency>
This dependency in addition to slf4j-log4j12-1.7.21.jar,it will pull slf4j-api-1.7.21.jar as well as log4j-1.2.17.jar into your project
Reference: http://www.slf4j.org/manual.html

Please add the following dependencies to pom to resolve this issue.
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-simple</artifactId>
<version>1.7.25</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.25</version>
</dependency>

As an alternative to the jar inclusion and pure maven solutions, you can include it from maven with gradle.
Example for version 1.7.25
// https://mvnrepository.com/artifact/org.slf4j/slf4j-simple
api group: 'org.slf4j', name: 'slf4j-simple', version: '1.7.25'
Put this within the dependencies of your build.gradle file.

In the Websphere case, you have an older version of slf4j-api.jar, 1.4.x. or 1.5.x lying around somewhere. The behavior you observe on tcServer, that is fail-over to NOP, occurs on slf4j versions 1.6.0 and later. Make sure that you are using slf4j-api-1.6.x.jar on all platforms and that no older version of slf4j-api is placed on the class path.

I am working in a project Struts2+Spring. So it need a dependency slf4j-api-1.7.5.jar.
If I run the project, I am getting error like
Failed to load class "org.slf4j.impl.StaticLoggerBinder"
I solved my problem by adding the slf4j-log4j12-1.7.5.jar.
So add this jar in your project to solve the issue.

As SLF4J Manual states
The Simple Logging Facade for Java (SLF4J) serves as a simple facade
or abstraction for various logging frameworks, such as
java.util.logging, logback and log4j.
and
The warning will disappear as soon as you add a binding to your class path.
So you should choose which binding do you want to use.
NoOp binding (slf4j-nop)
Binding for NOP, silently discarding all logging.
Check fresh version at https://search.maven.org/search?q=g:org.slf4j%20AND%20a:slf4j-nop&core=gav
Simple binding (slf4j-simple)
outputs all events to System.err. Only messages of level INFO and higher are printed. This binding may be useful in the context of small applications.
Check fresh version at https://search.maven.org/search?q=g:org.slf4j%20AND%20a:slf4j-simple&core=gav
Bindings for the logging frameworks (java.util.logging, logback, log4j)
You need one of these bindings if you are going to write log to a file.
See description and instructions at https://www.slf4j.org/manual.html#projectDep
My opinion
I would recommend Logback because it's a successor to the log4j project.
Check latest version of the binding for it at https://search.maven.org/search?q=g:ch.qos.logback%20AND%20a:logback-classic&core=gav
You get console output out of the box but if you need to write logs into file just put FileAppender configuration to the src/main/resources/logback.xml or to the src/test/resources/logback-test.xml just like this:
<?xml version="1.0" encoding="UTF-8"?>
<configuration>
<appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
<!-- encoders are assigned the type
ch.qos.logback.classic.encoder.PatternLayoutEncoder by default -->
<encoder>
<pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</pattern>
</encoder>
</appender>
<appender name="FILE" class="ch.qos.logback.core.FileAppender">
<file>logs/logs.log</file>
<encoder>
<pattern>%date %level [%thread] %logger{10} - %msg%n</pattern>
</encoder>
</appender>
<root level="debug">
<appender-ref ref="STDOUT" />
<appender-ref ref="FILE" />
</root>
<logger level="DEBUG" name="com.myapp"/>
</configuration>
(See detailed description in manual: https://logback.qos.ch/manual/configuration.html)

this can resolve using the same version. I tried this and solved it
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.5</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>1.7.5</version>
</dependency>

I added this dependency to resolve this issue:
https://mvnrepository.com/artifact/org.slf4j/slf4j-simple/1.7.25

Most likely your problem was because of <scope>test</scope> (in some cases also <scope>provided</scope>), as mentioned #thangaraj.
Documentation says:
This scope indicates that the dependency is not required for normal
use of the application, and is only available for the test compilation
and execution phases. Test dependencies aren’t transitive and are only present for test and execution classpaths.
So, if you don't need dependecies for test purposes then you can use instead of (what you will see in mvnrepository):
<!-- https://mvnrepository.com/artifact/org.slf4j/slf4j-nop -->
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-nop</artifactId>
<version>1.7.24</version>
<scope>test</scope>
</dependency>
Without any scopes (by default would be compile scope when no other scope is provided):
<!-- https://mvnrepository.com/artifact/org.slf4j/slf4j-nop -->
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-nop</artifactId>
<version>1.7.25</version>
</dependency>
This is the same as:
<!-- https://mvnrepository.com/artifact/org.slf4j/slf4j-nop -->
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-nop</artifactId>
<version>1.7.25</version>
<scope>compile</scope>
</dependency>

Here are my 5 cents...
I had the same issues while running tests. So I've fixed it by adding an implementation for the test runtime only. I'm using gradle for this project.
// https://mvnrepository.com/artifact/ch.qos.logback/logback-classic
testRuntimeOnly group: 'ch.qos.logback', name: 'logback-classic',
version: '1.2.3'

encountered the same problem on payara 5.191
jcl-over-slf4j together with slf4j-log4j12 solved the problem
<properties>
<slf4j.version>1.7.29</slf4j.version>
</properties>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>${slf4j.version}</version>
<type>jar</type>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>jcl-over-slf4j</artifactId>
<version>${slf4j.version}</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>${slf4j.version}</version>
</dependency>

As per the SLF4J Error Codes
Failed to load class org.slf4j.impl.StaticLoggerBinder
This warning message is reported when the org.slf4j.impl.StaticLoggerBinder class could not be loaded into memory. This happens when no appropriate SLF4J binding could be found on the class path. Placing one (and only one) of slf4j-nop.jar slf4j-simple.jar, slf4j-log4j12.jar, slf4j-jdk14.jar or logback-classic.jar on the class path should solve the problem.
Note that slf4j-api versions 2.0.x and later use the ServiceLoader mechanism. Backends such as logback 1.3 and later which target slf4j-api 2.x, do not ship with org.slf4j.impl.StaticLoggerBinder. If you place a logging backend which targets slf4j-api 2.0.x, you need slf4j-api-2.x.jar on the classpath. See also relevant faq entry.
SINCE 1.6.0 As of SLF4J version 1.6, in the absence of a binding, SLF4J will default to a no-operation (NOP) logger implementation.
If you are responsible for packaging an application and do not care about logging, then placing slf4j-nop.jar on the class path of your application will get rid of this warning message. Note that embedded components such as libraries or frameworks should not declare a dependency on any SLF4J binding but only depend on slf4j-api. When a library declares a compile-time dependency on a SLF4J binding, it imposes that binding on the end-user, thus negating SLF4J's purpose.

for me the total fix was:
1
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.5</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>1.7.5</version>
</dependency>
plus
2 create file log4j.properties
and add inside:
# Root logger option
log4j.rootLogger=INFO, stdout
# Direct log messages to stdout
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n
else I got some exceptions in the console.

According to SLF4J official documentation
Failed to load class org.slf4j.impl.StaticLoggerBinder
This warning message is reported when the
org.slf4j.impl.StaticLoggerBinder class could not be loaded into
memory. This happens when no appropriate SLF4J binding could be found
on the class path. Placing one (and only one) of slf4j-nop.jar,
slf4j-simple.jar, slf4j-log4j12.jar, slf4j-jdk14.jar or
logback-classic.jar on the class path should solve the problem.
Simply add this jar along with slf4j api.jar to your classpath to get things done.
Best of luck

I solve it adding this library: slf4j-simple-1.7.25.jar
You can download this in official web https://www.slf4j.org/download.html

For me the issue was:
Using Hibernate, I saw that it already used slf4j, and it was in my classpath already, so I decided to use it.
The next step - adding imlementor for slf4j, so I added to maven:
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-jdk14</artifactId>
<version>1.7.25</version>
</dependency>
But it failed with error! SLF4J: Failed to load class “org.slf4j.impl.StaticLoggerBinder”
The solution was:
Hibernate's dependency of slf4j was version 1.7.26, and I added minor version dependency 1.7.25. So when I fixed this - all became OK

I know this post is a little old, but in case anyone else runs into this problem:
Add slf4j-jdk14-X.X.X.jar to your CLASSPATH (where X.X.X is the version number - e.g. slf4j-jdk14-1.7.5.jar).
HTH
Peter