[java] java.lang.NoClassDefFoundError: org.slf4j.LoggerFactory

I am getting the error as mentioned below, while running the feed utility. I am trying to load an image "logo.png". The slf4j jar file is also available in the runtime classpath. But still I am getting this error.

Oct 16, 2012 7:34:11 PM com.ibm.commerce.foundation.dataload.FeedRetriever  invokeDataLoad
SEVERE: An error occurred while performing data load.
Throwable occurred: com.ibm.commerce.foundation.dataload.exception.DataLoadException: 
An error occurred while executing the data load. 

java.lang.NoClassDefFoundError: org.slf4j.LoggerFactory

    at com.ibm.commerce.foundation.dataload.DataLoaderMain.execute(DataLoaderMain.java:664)
    at com.ibm.commerce.content.commands.DataLoadInvoker.execute(DataLoadInvoker.java:101)
    at com.ibm.commerce.foundation.dataload.FeedRetriever.invokeDataLoad(FeedRetriever.java:244)
    at com.ibm.commerce.foundation.dataload.FeedRetriever.execute(FeedRetriever.java:172)
    at com.ibm.commerce.foundation.dataload.FeedRetriever.main(FeedRetriever.java:321)
Caused by: java.lang.RuntimeException: java.lang.NoClassDefFoundError: org.slf4j.LoggerFactory
    at com.ibm.commerce.foundation.dataload.DataLoaderMain.execute(DataLoaderMain.java:488)
    ... 4 more
Caused by: java.lang.NoClassDefFoundError: org.slf4j.LoggerFactory
    at org.apache.wink.client.ClientConfig.<clinit>(ClientConfig.java:52)
    at java.lang.J9VMInternals.initializeImpl(Native Method)
    at java.lang.J9VMInternals.initialize(J9VMInternals.java:200)
    at java.lang.J9VMInternals.initialize(J9VMInternals.java:167)
    at com.ibm.commerce.foundation.dataload.feedreader.AtomReader.getFeed(AtomReader.java:104)
    at com.ibm.commerce.foundation.dataload.feedreader.AtomReader.getEntries(AtomReader.java:147)
    at com.ibm.commerce.foundation.dataload.feedreader.AtomReader.getEntries(AtomReader.java:1)
    at com.ibm.commerce.foundation.dataload.feedreader.BaseFeedReader.init(BaseFeedReader.java:252)
    at com.ibm.commerce.foundation.dataload.AbstractBusinessObjectLoader.initializeDataReaders(AbstractBusinessObjectLoader.java:1344)
    at com.ibm.commerce.foundation.dataload.AbstractBusinessObjectLoader.init(AbstractBusinessObjectLoader.java:369)
    at com.ibm.commerce.foundation.dataload.BusinessObjectLoader.init(BusinessObjectLoader.java:65)
    at com.ibm.commerce.foundation.dataload.DataLoaderMain.execute(DataLoaderMain.java:431)
    ... 4 more
Caused by: java.lang.ClassNotFoundException: org.slf4j.LoggerFactory
    at java.lang.ClassNotFoundException.<init>(ClassNotFoundException.java:76)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:396)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:660)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:358)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:626)
    ... 16 more
Oct 16, 2012 7:34:11 PM com.ibm.commerce.foundation.dataload.FeedRetriever main
SEVERE: An error occurred while performing data load.
Throwable occurred: com.ibm.commerce.foundation.dataload.exception.DataLoadException: An error has occurred.  If this problem persists, contact product support.
    at com.ibm.commerce.foundation.dataload.FeedRetriever.invokeDataLoad(FeedRetriever.java:247)
    at com.ibm.commerce.foundation.dataload.FeedRetriever.execute(FeedRetriever.java:172)
    at com.ibm.commerce.foundation.dataload.FeedRetriever.main(FeedRetriever.java:321)

This question is related to java

The answer is


Add the following jars to the class path or lib folder

  1. slf4j-api-1.7.2.jar
  2. slf4j-jdk14-1.7.2.jar

I believe the answer is outlined on the slf4j web-site (Failed to load class org.slf4j.impl.StaticLoggerBinder)

For a very quick solution I suggest adding no-operation (NOP) logger implementation (slf4j-nop.jar)

For example, if using maven:

<dependency>
    <groupId>org.slf4j</groupId>
    <artifactId>slf4j-nop</artifactId>
    <version>${slf4j-nop-version}</version>
</dependency>

If you are facing java.lang.NoClassDefFoundError: org.slf4j.LoggerFactory

Add slf4j-log4j12 jar in the library folder of the project


You need slf4j-api library and slf4j-log4j12-1.7.25 jar. Copy this jars in your project-> WEBINF-> lib folder and in tomcat server lib folder to execute successfully.


get the compatible version of this jar slf4j-jdk14 and add it as a dependency. this solved the problem for me.


this worked for me /properties/maven uncheck resolve dependencies from Workspace projects.


This error occurs because of referenced jars are not checked in our project's order and export tab.

Choose Project ->ALT+Enter->Java Build Path ->Order and Export->check necessary jar files into your project.

Finally clean your project and run.It will run successfully.


I also had the similar problem. I had a maven project and was testing rabbitmq. Firstly it showed me the similar error then I added all the SLF4J dependencies in the maven project and then error changed to "Maven SLF4J: Class path contains multiple SLF4J bindings". Here is the complete list of dependencies from pom.xlm

<dependencies>
    <dependency>
        <groupId>com.rabbitmq</groupId>
        <artifactId>amqp-client</artifactId>
        <version>4.0.0</version>
    </dependency>
    <dependency>
        <groupId>org.apache.commons</groupId>
        <artifactId>commons-lang3</artifactId>
        <version>3.0</version>
    </dependency>
    <dependency>
       <groupId>org.slf4j</groupId>
       <artifactId>slf4j-simple</artifactId>
       <version>1.7.21</version>
       <scope>compile</scope>
    </dependency>
</dependencies> 

It worked finally.


use maven it will download all the required jar files for you.

in this case you need the below jar files:

slf4j-log4j12-1.6.1.jar slf4j-api-1.6.1.jar

These jars will also depend on the cassandra version which you are running. There are dependencies with cassandra version , jar version and jdk version you use.

You can use : jdk1.6 with : cassandra 1.1.12 and the above jars.


First, check the dependency hierarchy than to exclude all slf4j jars from other dependencies and add separate slf4j as dependencies.


You have to provide one of the various SLF4J implementation .jar files in the classpath, as well as the interface .jar file. This is documented.


The perfect solution which works undoubtedly is to just add these packages to your app:
https://mvnrepository.com/artifact/org.slf4j/slf4j-api/1.7.2
http://archive.apache.org/dist/logging/log4j/1.2.16/

after adding so you may encounter following WARNING which you can simply ignore!

SLF4J: No SLF4J providers were found. SLF4J: Defaulting to no-operation (NOP) logger implementation SLF4J: See http://www.slf4j.org/codes.html#noProviders for further details.

credits: https://www.javacodegeeks.com/2018/02/fix-exception-thread-main-java-lang-noclassdeffounderror-org-slf4j-loggerfactory-java.html


You can use bellow dependency

<dependency>
        <groupId>log4j</groupId>
        <artifactId>log4j</artifactId>
        <version>1.2.17</version>
    </dependency>
    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-api</artifactId>
        <version>1.7.7</version>
    </dependency>
    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-log4j12</artifactId>
        <version>1.7.7</version>
    </dependency>

When we use the slf4j api jar, we need any of the logger implementations like log4j. On my system, we have the complete set and it works fine.

1. slf4j-api-1.5.6.jar
2. slf4j-log4j12-1.5.6.jar
3. **log4j-1.2.15.jar**

Right click on project properties and follow below steps Project Properties" --> "Deployment Assembly", adding "Java Build Path Entries -> Maven Dependencies


To be more specific if you are missing the class com.vaadin.external.org.slf4j.LoggerFactory add the below dependency.

<dependency>
    <groupId>com.vaadin.external.slf4j</groupId>
    <artifactId>vaadin-slf4j-jdk14</artifactId>
    <version>1.6.1</version>
</dependency>

If you are missing any other org.slf4j.LoggerFactory, just go to Maven central class name search and search for the exact class name to determine what exact dependency you are missing.


I was facing a similar issue and below line fixed the issue for me.

    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-api</artifactId>
    </dependency>

Edit: I realized that I was using spring boot and the version of the dependency was getting pulled from spring-boot-starter-parent.


I tried other solutions and the exception didn't go away. So I decompiled the entire jose4j 0.6.5 jar with a Java Decomplier and look at its pom.xml.

I realised it has a specific dependency on slf4j-api, version 1.7.21: enter image description here

So in my project's pom.xml, I added the exact same dependency, updated my Maven project so that it downloads this jar into my repository and the exception was gone.

However it may bring up another error caused by slf4j itself:

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.

To overcome this issue, I added the following into my project's pom.xml. So altogether you need to add the following to your pom.xml and my jose4j ran without anymore issues:

<dependency>
    <groupId>org.slf4j</groupId>
    <artifactId>slf4j-api</artifactId>
    <version>1.7.21</version>
</dependency>   

<dependency>
   <groupId>org.slf4j</groupId>
   <artifactId>slf4j-simple</artifactId>
   <version>1.6.4</version>
</dependency>

Remember to update your Maven project after amending your pom.xml.

(Right-click Project folder in Eclipse -> Maven -> Update Project..)


When you copy dependency from maven repository there is:

<scope>test</scope>

Try to remove it from dependencies in pom.xml like this.

<!-- https://mvnrepository.com/artifact/ch.qos.logback/logback-classic -->
<dependency>
    <groupId>ch.qos.logback</groupId>
    <artifactId>logback-classic</artifactId>
    <version>1.2.3</version>
</dependency>

This works for me. I hope it would be helpful for someone else.


Download slf4j-1.7.5.zip

It holds different jar files.

Go to -> Integration folder after extracting zip and include following jar files

  1. slf4j-api-2.0.99
  2. slf4j-simple-1.6.99
  3. junit-3.8.1

make sure your MANIFEST.MF contains the name of the referenced jar in my application was slf4j-api-*. jar.


Add a SLF4J implementation (as you only have its API):

<dependency>
    <groupId>org.slf4j</groupId>
    <artifactId>slf4j-log4j12</artifactId>
    <version>1.7.26</version>
</dependency>

You need slf4j-api library. For most cases only slf4j-api and slf4j-jkd14 are only required:

Here you can download the version 1.7.2:

slf4j-api-1.7.2.jar
slf4j-jkd14-1.7.2jar

If you need an example to see how these are used, refers to this tutorial: http://www.ibm.com/developerworks/java/library/j-hangman-app/index.html

All the code for the tutorial is available


The LoggerFactory class is msising according to the error message:

java.lang.NoClassDefFoundError: org.slf4j.LoggerFactory

Apparently, the slf4j.jar file is not getting loaded for some reason.