log4j-slf4j-impl cannot be present with log4j-to-slf4j 之类的问题，解决maven依赖冲突

如题所示，本文主要用户解决maven的依赖冲突，并提供通用的解决方案。
先放错误

SLF4J: Class path contains multiple SLF4J bindings.
SLF4J: Found binding in [jar:file:/home/liao/.m2/repository/org/apache/logging/log4j/log4j-slf4j-impl/2.15.0/log4j-slf4j-impl-2.15.0.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/home/liao/.m2/repository/org/slf4j/slf4j-log4j12/1.6.1/slf4j-log4j12-1.6.1.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/home/liao/.m2/repository/ch/qos/logback/logback-classic/1.2.4/logback-classic-1.2.4.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.apache.logging.slf4j.Log4jLoggerFactory]
Exception in thread "main" java.lang.ExceptionInInitializerError
	at com.baomidou.mybatisplus.generator.config.builder.Entity$Builder.(Entity.java:333)
	at com.baomidou.mybatisplus.generator.config.StrategyConfig.(StrategyConfig.java:116)
	at com.baomidou.mybatisplus.generator.config.StrategyConfig.(StrategyConfig.java:35)
	at com.baomidou.mybatisplus.generator.config.StrategyConfig$Builder.(StrategyConfig.java:379)
	at com.baomidou.mybatisplus.generator.FastAutoGenerator.(FastAutoGenerator.java:75)
	at com.baomidou.mybatisplus.generator.FastAutoGenerator.create(FastAutoGenerator.java:85)
	at com.xiaomi.browser.miuibn.operation.MybatisPlusCodeGene.main(MybatisPlusCodeGene.java:24)
Caused by: org.apache.logging.log4j.LoggingException: log4j-slf4j-impl cannot be present with log4j-to-slf4j
	at org.apache.logging.slf4j.Log4jLoggerFactory.validateContext(Log4jLoggerFactory.java:60)
	at org.apache.logging.slf4j.Log4jLoggerFactory.newLogger(Log4jLoggerFactory.java:44)
	at org.apache.logging.slf4j.Log4jLoggerFactory.newLogger(Log4jLoggerFactory.java:33)
	at org.apache.logging.log4j.spi.AbstractLoggerAdapter.getLogger(AbstractLoggerAdapter.java:53)
	at org.apache.logging.slf4j.Log4jLoggerFactory.getLogger(Log4jLoggerFactory.java:33)
	at org.slf4j.LoggerFactory.getLogger(LoggerFactory.java:358)
	at org.slf4j.LoggerFactory.getLogger(LoggerFactory.java:383)
	at com.baomidou.mybatisplus.generator.config.builder.Entity.(Entity.java:48)
	... 7 more
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此类日志是出现依赖冲突的常见形式，从日志中我们可以看到Caused by: org.apache.logging.log4j.LoggingException: log4j-slf4j-impl cannot be present with log4j-to-slf4j我们能大概看到，是log4j日志组件出现了问题。虽然从Cause by得出一点信息，但最想要解决问题，还是得从warning入手。

因为只有得知了，产生冲突的是那些jar，才能想办法排除，回到报错开头

SLF4J: Class path contains multiple SLF4J bindings.
SLF4J: Found binding in [jar:file:/home/liao/.m2/repository/org/apache/logging/log4j/log4j-slf4j-impl/2.15.0/log4j-slf4j-impl-2.15.0.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/home/liao/.m2/repository/org/slf4j/slf4j-log4j12/1.6.1/slf4j-log4j12-1.6.1.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/home/liao/.m2/repository/ch/qos/logback/logback-classic/1.2.4/logback-classic-1.2.4.jar!/org/slf4j/impl/StaticLoggerBinder.class]
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定位到问题Class path contains multiple SLF4J bindings.有多个与sl4j绑定了，并且给出了，下面的binding的jar和类，所以我们只需要，找到这些依赖，并指出采用哪一个，排除那些即可。

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下面提供两种方式：

1. mvn dependency:tree 列出依赖树，并查找，对应依赖

因为一些原因，不便列出我项目的依赖，只能列出一个demo

[INFO] +- org.docx4j:docx4j:jar:3.3.5:compile 
[INFO] |  +- org.slf4j:slf4j-log4j12:jar:1.7.21:compile 
[INFO] |  +- log4j:log4j:jar:1.2.17:compile 
[INFO] +- ch.qos.logback:logback-classic:jar:1.1.7:compile 
[INFO] +- ch.qos.logback:logback-core:jar:1.1.7:compile
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2. 直接根据路径在idea的external libraries里面寻找
   
   例如，从SLF4J: Found binding in [jar:file:/home/liao/.m2/repository/org/apache/logging/log4j/log4j-slf4j-impl/2.15.0/log4j-slf4j-impl-2.15.0.jar!/org/slf4j/impl/StaticLoggerBinder.class]我们可以得出信息jar路径是org/apache/logging/log4j/log4j-slf4j-impl/2.15.0/log4j-slf4j-impl-2.15.0.jar，我们只需要根据前缀路径，即可得到依赖信息
   

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上述两中放到，最主要的是得到依赖的artifactId 与groupId，例如上面的jar的分别是org.apache.logging.log4j和log4j-slf4j-impl，得出所以冲突包后，只需要在pom中添加如下内容即可解决。

 
 <dependency>
     <groupId>org.apache.logging.log4jgroupId>
     <artifactId>log4j-slf4j-implartifactId>
     <version>2.17.0version>
     <exclusions>
         <exclusion>
             <groupId>org.slf4jgroupId>
             <artifactId>slf4j-apiartifactId>
         exclusion>
         <exclusion>
             <groupId>ch.qos.logbackgroupId>
             <artifactId>logback-classicartifactId>
         exclusion>
     exclusions>
 dependency>
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再运行，就解决了依赖冲突的问题。对于这种类型的冲突，理论上，都可以采用此种方法解决

参考链接：
SLF4J Warning: Class Path Contains Multiple SLF4J Bindings