[FIXED] SLF4JLoggerContext cannot be cast to LoggerContext

Issue

I get known error:

Getting Exception org.apache.logging.slf4j.SLF4JLoggerContext cannot be cast to org.apache.logging.log4j.core.LoggerContext

I know that the solution is to remove log4j-to-slf4j from the classpath, as described here: href="https://stackoverflow.com/questions/25891737/getting-exception-org-apache-logging-slf4j-slf4jloggercontext-cannot-be-cast-to">Getting Exception org.apache.logging.slf4j.SLF4JLoggerContext cannot be cast to org.apache.logging.log4j.core.LoggerContext

But the project is build with maven and contains spring-boot-starter-web which imports the dependency. I can not get rid from spring-boot-starter-web, and I need log4j.

Here is the pom:

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>ru.beinteractive</groupId>
    <artifactId>newlps</artifactId>
    <packaging>war</packaging>
    <version>1.0</version>
    <name>newlps</name>
    <url>http://maven.apache.org</url>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.0.RELEASE</version>
    </parent>   
    <dependencies>  
        <dependency>
            <groupId>com.google.cloud</groupId>
            <artifactId>google-cloud-storage</artifactId>
            <version>1.14.0</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-tomcat</artifactId>
            <scope>provided</scope>
        </dependency>       
        <dependency>
            <groupId>com.jayway.jsonpath</groupId>
            <artifactId>json-path</artifactId>
            <scope>test</scope>
        </dependency>       
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <scope>test</scope>
        </dependency>   
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-api</artifactId>
        </dependency>
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-core</artifactId>
        </dependency>
        <dependency>
            <groupId>com.google.code.gson</groupId>
            <artifactId>gson</artifactId>
            <type>jar</type>
        </dependency>
        <dependency>
            <groupId>com.google.code.externalsortinginjava</groupId>
            <artifactId>externalsortinginjava</artifactId>
            <version>0.1.9</version>
        </dependency>
        <dependency>
            <groupId>commons-io</groupId>
            <artifactId>commons-io</artifactId>
            <version>2.4</version>
        </dependency>
        <dependency>
            <groupId>org.mongodb</groupId>
            <artifactId>mongodb-driver</artifactId>
        </dependency>
        <dependency>
           <groupId>org.json</groupId>
           <artifactId>json</artifactId>
           <type>jar</type>
           <version>20171018</version>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-csv</artifactId>
            <version>1.5</version>
            <type>jar</type>
        </dependency>
        <dependency>
            <groupId>redis.clients</groupId>
            <artifactId>jedis</artifactId>
        </dependency>
        <dependency>
           <groupId>org.springframework.boot</groupId>
           <artifactId>spring-boot</artifactId>
           <type>jar</type>
        </dependency>
        <dependency>
            <groupId>org.quartz-scheduler</groupId>
            <artifactId>quartz</artifactId>
        </dependency>
        <dependency>
            <groupId>org.quartz-scheduler</groupId>
            <artifactId>quartz-jobs</artifactId>
            <version>2.2.1</version>
        </dependency>
        <dependency>
           <groupId>org.seleniumhq.selenium</groupId>
           <artifactId>selenium-java</artifactId>
           <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>com.opera</groupId>
            <artifactId>operadriver</artifactId>
            <scope>test</scope>
            <version>1.5</version>
            <exclusions>
                <exclusion>
                    <groupId>org.seleniumhq.selenium</groupId>
                    <artifactId>selenium-remote-driver</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.eclipse.jetty</groupId>
                <artifactId>jetty-maven-plugin</artifactId>
                <version>9.4.8.v20171121</version>
                <configuration>
                    <webAppConfig>
                        <allowDuplicateFragmentNames>
                            true
                        </allowDuplicateFragmentNames>
                    </webAppConfig>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-war-plugin</artifactId>
                <configuration>
                    <warName>newlps</warName>
                </configuration>
            </plugin>
        </plugins>      
    </build>
    <repositories>
        <repository>
            <id>spring-snapshots</id>
            <name>Spring Snapshots</name>
            <url>https://repo.spring.io/snapshot</url>
            <snapshots>
                <enabled>true</enabled>
            </snapshots>
        </repository>
        <repository>
            <id>spring-releases</id>
            <url>https://repo.spring.io/libs-release</url>
            <snapshots>
                <enabled>true</enabled>
            </snapshots>
        </repository>
        <repository>
            <id>spring-milestones</id>
            <name>Spring Milestones</name>
            <url>https://repo.spring.io/milestone</url>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
        </repository>
    </repositories>
    <pluginRepositories>
        <pluginRepository>
            <id>repository.spring.release</id>
            <name>Spring GA Repository</name>
            <url>https://repo.spring.io/plugins-release/</url>
        </pluginRepository>
    </pluginRepositories>
    <properties>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
    </properties>
</project>

Solution

In Maven, you can exclude a sub dependency from a dependency. Try this:

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
    <exclusions>
    <exclusion>
        <groupId>org.apache.logging.log4j</groupId>
        <artifactId>log4j-to-slf4j</artifactId>
    </exclusion>
    </exclusions>
</dependency>

Answered By - Herr Derb
Answer Checked By - Candace Johnson (JavaFixing Volunteer)