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Why would a "No SLF4J" provider found error occur when SLF4J is in Maven pom.xml file?

I am currently getting the below errors when trying to run a Spring Java program.
SLF4J: No SLF4J providers were found.
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See https://www.slf4j.org/codes.html#noProviders for further details.
SLF4J: Class path contains SLF4J bindings targeting slf4j-api versions 1.7.x or earlier.
SLF4J: Ignoring binding found at [jar:file:/C:/Users/user/.m2/repository/ch/qos/logback/logback-classic/1.2.11/logback-classic-1.2.11.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Ignoring binding found at [jar:file:/C:/Users/user/.m2/repository/org/apache/logging/log4j/log4j-slf4j-impl/2.19.0/log4j-slf4j-impl-2.19.0.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: See https://www.slf4j.org/codes.html#ignoredBindings for an explanation.
Here is the section in the pom.xml file that has the SLF4J and Log4J dependencies. This same section has worked in previous projects.
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>2.0.5</version>
</dependency>
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-slf4j-impl</artifactId>
<version>2.19.0</version>
</dependency>
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-api</artifactId>
<version>2.19.0</version>
</dependency>
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-core</artifactId>
<version>2.19.0</version>
</dependency>
I don't have any components that are targeting indings for slf4j-api version 1..x or earlier. This error message seems to both say that I don't have SLF4J and that I have the wrong version.
If there are any thoughts on how to resolve this, I would appreciate it. Thank you!
I have tried using different dependencies in the pom.xml file, but ultimately these have worked in a previous program. I have also tried looking at dependencies that might also use SLF4J and excluding SLF4J from them, but I am still getting an error message. I have tried solutions from other similar questions asked but keep getting the same error.

Based on this documentation:
Due to a break in compatibility in the SLF4J binding, as of release 2.19.0 two SLF4J to Log4j Adapters are provided.
log4j-slf4j-impl should be used with SLF4J 1.7.x releases or older.
log4j-slf4j2-impl should be used with SLF4J 2.0.x releases or newer.
Applications that take advantage of the Java Module System should use SLF4J 2.0.x and log4j-slf4j2-impl.
So the simplest way (if you need SLF4J 2) is to use <artifactId>log4j-slf4j2-impl</artifactId>. The other thing you can do is to revert back to slf4j-api 1.7.x.
Other notes:
The SLF4J log shows that logback-classic is also present in the dependency tree. You need to select either logback-classic or the log4j binding. Run mvn dependency:tree on your project to find where logback-classic is being added.
If you want to keep logback-classic, then same as mentioned above, you need to use the logback-classic compatible with SLF4J 2.

missing org/eclipse/m2e/core/embedder/IMavenExecutionContextFactory [duplicate]

My pom.xml contains only one reference to SLF4J:
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-jdk14</artifactId>
<version>1.5.10</version>
</dependency>
I am getting this 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.
I checked that URL and indeed it provides a solution: "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. "
My question is: which classpath?
The system's %CLASSPATH%? (I don't have one! I will need to create it specifically for this)
Eclipse's project .classpath? (I think I tried this but it didn't help)
Other?
I found quite a few postings on the subject here on SO, but they all quote the same answer: "place ... on the class path".
Which classpath?

First of all in order to add SLF4J you should put ONE and only ONE of these dependencies in your pom.xml. It depends on what implementation you choose to use. Every dependency you add in the pom.xml is added automatically in the classpath. As long as you are using Eclipse there is no need to modify the system's %CLASSPATH%?
<dependency>
<groupId>ch.qos.logback</groupId>
<artifactId>logback-classic</artifactId>
<version></version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-simple</artifactId>
<version></version>
<scope>compile</scope>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version></version>
<scope>compile</scope>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-jdk14</artifactId>
<version></version>
<scope>compile</scope>
</dependency>
Last but not least you will have the error SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
Eclipse Juno and Indigo, when using the bundled maven version(m2e), are not suppressing the message SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder". This behaviour is present from the m2e version 1.1.0.20120530-0009 and onwards.
Although, this is indicated as an error your logs will be saved normally. The highlighted error will still be present until there is a fix of this bug. More about this in the m2e support site.
The current available solution in order to suppress this message is to use an external maven version rather than the bundled version of Eclipse. You can find about this solution and more details regarding this bug in the question below.
SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder". error

Problem:
I'm using Maven to manage my dependencies. In my case, the reason I was getting this error was because I had more than one slf4j-simple jar in my system on my class path. The SLF4J documentation states:
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.
Solution:
Search for the following jars in your file system and remove all copies other than the one in .m3:
slf4j-nop
slf4j-simple
slf4j-log4j12
slf4j-jdk14
logback-classic

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.

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