ERROR SLF4J: Class path contains multiple SLF4J bindings jenkins cobertura maven

Question

I'm with this error on third day already and I can't resolved. There is something that I can't grasp on and no matter what I do the error still persists.

I'm reading a book called "Jenkins a definitive guide" (http://www.wakaleo.com/books/jenkins-the-definitive-guide) and I'm stuck on chapter two. Basically is a example of how to use Jenkins with Javadoc, JUnit and Cobertura plugin for Jenkins. Everything works until I get to Cobertura plugin part, where I get next error:

[ERROR] SLF4J: Class path contains multiple SLF4J bindings.
SLF4J: Found binding in [jar:file:/C:/Windows/System32/config/systemprofile/.m2/repository/ch/qos/logback/logback-classic/1.0.13/logback-classic-1.0.13.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/C:/Windows/System32/config/systemprofile/.m2/repository/org/slf4j/slf4j-simple/1.6.1/slf4j-simple-1.6.1.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: See http://www.slf4j.org/codes.html#multiple_bindings for an explanation.
SLF4J: Actual binding is of type [ch.qos.logback.classic.util.ContextSelectorStaticBinder]

I have seen other problems like mine and the conclusion I got is that I have either to include o exclude a dependency in my pom.xml file/s (this examples only uses pom files at this stage). My pom.xml file that has slf4j-simple looks like this:

<project>
......
    <dependencies>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-simple</artifactId>
            <version>1.6.1</version>
        </dependency>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-api</artifactId>
            <version>1.6.1</version>
        </dependency>
    </dependencies>
</project>

and there is no explicit dependency to logback-classic hence I don't know in what dependency is being used. I tried to use dependency plugin for jenkins and I got this result:

[INFO] --- maven-dependency-plugin:2.8:tree (default-cli) @ gameoflife-web ---
[INFO] com.wakaleo.gameoflife:gameoflife-web:war:1.0-SNAPSHOT
[INFO] +- com.wakaleo.gameoflife:gameoflife-core:jar:1.0-SNAPSHOT:compile
[INFO] +- org.springframework:spring-webmvc:jar:3.0.2.RELEASE:compile
[INFO] |  +- org.springframework:spring-asm:jar:3.0.2.RELEASE:compile
[INFO] |  +- org.springframework:spring-beans:jar:3.0.2.RELEASE:compile
[INFO] |  +- org.springframework:spring-context:jar:3.0.2.RELEASE:compile
[INFO] |  |  \- org.springframework:spring-aop:jar:3.0.2.RELEASE:compile
[INFO] |  +- org.springframework:spring-context-support:jar:3.0.2.RELEASE:compile
[INFO] |  \- org.springframework:spring-expression:jar:3.0.2.RELEASE:compile
[INFO] +- org.springframework:spring-core:jar:3.0.2.RELEASE:compile
[INFO] |  \- commons-logging:commons-logging:jar:1.1.1:compile
[INFO] +- org.springframework:spring-web:jar:3.0.2.RELEASE:compile
[INFO] |  \- aopalliance:aopalliance:jar:1.0:compile
[INFO] +- javax.servlet:jstl:jar:1.2:compile
[INFO] +- javax.servlet:servlet-api:jar:2.5:provided
[INFO] +- org.mockito:mockito-all:jar:1.8.5:test
[INFO] +- org.easytesting:fest-assert:jar:1.4:compile
[INFO] |  \- org.easytesting:fest-util:jar:1.1.6:compile
[INFO] +- org.slf4j:slf4j-simple:jar:1.6.1:compile
[INFO] +- org.slf4j:slf4j-api:jar:1.6.1:compile
[INFO] +- junit:junit:jar:4.11:test
[INFO] |  \- org.hamcrest:hamcrest-core:jar:1.3:test
[INFO] \- org.hamcrest:hamcrest-all:jar:1.1:test

Maybe I'm blind, but I still can't see who uses logback-classic (by the way I'm not sure what values are correct for and 对于logback-classic )。我试图删除slf4j依赖项，但错误消失了，但我没有收到任何 cobertura 报告。我试图排除的logback经典与

    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-simple</artifactId>
        <version>1.6.1</version>
        <exclusions>
            <exclusion>
                <groupId>ch.qos.logback</groupId>
                <artifactId>logback-classic</artifactId>
            </exclusion>
        </exclusions>
    </dependency>
    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-api</artifactId>
        <version>1.6.1</version>
        <exclusions>
            <exclusion>
                <groupId>ch.qos.logback</groupId>
                <artifactId>logback-classic</artifactId>
            </exclusion>
        </exclusions>
    </dependency>

并且错误仍然存​​在。我不知道该怎么办了，请帮忙！

Answer 1

您试图从 slf 依赖项本身中排除 logback-classic。问题是，正如此处提到的，您在类路径中使用了多个绑定。实际的方法是在使用它的依赖项中保留对 logback-classic 的排除，而不是在 slf4j 依赖项中。不幸的是，我不确定你的哪个 jar 引用了 slf4j 导致了这个问题。一种解决方法是，使用 Ctrl+Sft+T 查看不同 jar 中是否存在 StaticLoggerBinder 类，并将 logback-classic 排除项放入其中。其他解决方法是，您可以尝试保留排除，作为反复试验。这些只是解决方法，但概念是相同的。我们需要在类路径中找到引用 logback-classic 的其他依赖项