Maven SLF4J：类路径包含多个SLF4J绑定

Question

我在运行java代码时遇到以下运行时异常。有人能帮我解决绑定冲突吗。

    SLF4J: Class path contains multiple SLF4J bindings.
SLF4J: Found binding in [jar:file:/C:/Users/Air/Desktop/sms/slf4j-1.7.7/slf4j-android-1.7.7.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/C:/Users/Air/Desktop/sms/slf4j-1.7.7/slf4j-jcl-1.7.7.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/C:/Users/Air/Desktop/sms/slf4j-1.7.7/slf4j-jdk14-1.7.7.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/C:/Users/Air/Desktop/sms/slf4j-1.7.7/slf4j-log4j12-1.7.7.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/C:/Users/Air/Desktop/sms/slf4j-1.7.7/slf4j-nop-1.7.7.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/C:/Users/Air/Desktop/sms/slf4j-1.7.7/slf4j-simple-1.7.7.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 [org.slf4j.impl.AndroidLoggerFactory]
Exception in thread "main" java.lang.ExceptionInInitializerError
Caused by: java.lang.RuntimeException: Fatal error in constructor!
    ... 2 more

Answer 1

此错误意味着您的类路径中有多个SLF4J实现。寻找错误具体在说什么。i、 e:SLf4J:在..中找到绑定 （这将打印找到StaticLoggerBinder.class实例的所有jar文件）。从类路径中删除所有这样的jar，除了其StaticLoggerBinder的jar。您需要的类实现。

Answer 2

您似乎有几个SLF4J的实现；您应该排除所有不必要的

Answer 3

运行mvn dependency:tree并搜索哪个依赖项具有您不想要的slf4j实现，然后使用依赖项排除来排除它们，如：

<dependency>
    <groupId>org.someexternallib</groupId>
    <artifactId>someexternallibartifact</artifactId>
    <version>...</version>

    <exclusions>
       <exclusion> 
          <groupId>org.slf4j</groupId>
          <artifactId>slf4j-log4j12</artifactId>
       </exclusion>
       <exclusion> 
          <groupId>log4j</groupId>
          <artifactId>log4j</artifactId>
      </exclusion>
    </exclusions> 
</dependency>