[FIXED] Avoid log4j-to-slf4j to download automatically

Issue

I have a project where log4j-to-slf4j-2.17.1.jar is automatically downloading as a part of dependency. I have added the exclusions tag as well. But still maven is downloading it.

To note that, I have specified the log4j2 version in the properties tag of the pom.xml. And it is downloading log4j-api-2.17.1.jar(which is expected) as well log4j-to-slf4j-2.17.1.jar(which is not required).

Any work arounds to resolve this? Please note that, I have checked to see that the jar is not available in classpath as well.

Exclusion in pom.xml:

<dependency>
    <groupId>org.apache.logging.log4j</groupId>
    <artifactId>log4j-api</artifactId>
    <exclusions>
        <exclusion>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-to-slf4j</artifactId>
            <version>2.17.1</version>
        </exclusion>
    </exclusions>
</dependency>

Classpath:

<?xml version="1.0" encoding="UTF-8"?>
<classpath>
    <classpathentry kind="src" output="target/classes" path="src/main/java">
        <attributes>
            <attribute name="optional" value="true"/>
            <attribute name="maven.pomderived" value="true"/>
        </attributes>
    </classpathentry>
    <classpathentry excluding="**" kind="src" output="target/classes" path="src/main/resources">
        <attributes>
            <attribute name="maven.pomderived" value="true"/>
        </attributes>
    </classpathentry>
    <classpathentry kind="src" output="target/test-classes" path="src/test/java">
        <attributes>
            <attribute name="optional" value="true"/>
            <attribute name="maven.pomderived" value="true"/>
            <attribute name="test" value="true"/>
        </attributes>
    </classpathentry>
    <classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-1.8">
        <attributes>
            <attribute name="maven.pomderived" value="true"/>
        </attributes>
    </classpathentry>
    <classpathentry kind="con" path="org.eclipse.m2e.MAVEN2_CLASSPATH_CONTAINER">
        <attributes>
            <attribute name="maven.pomderived" value="true"/>
        </attributes>
    </classpathentry>
    <classpathentry kind="output" path="target/classes"/>
</classpath>

Solution

log4j-api doesn't depends on log4j-to-slf4j so adding exclusion in log4j-api don't do anything.

Use mvn dependency:tree and check which direct dependency brings log4j-to-slf4j as transitive dependency then add exclusion there, also version is not required in exclusion since there will be only one version as dependency to an artifact.

Answered By - Karthikeyan Vaithilingam
Answer Checked By - Marie Seifert (JavaFixing Admin)