问题描述：springboot启动异常，启动后没有日志打印。

 问题原因：

问题应对：

1. 是不是项目没起来---->打印的日志数据，到这里就不打印了，在run方法后面加了一行输入print，当启动之后使用debug，能运行到此行，说明正常启动成功的。

2.是不是日志框架冲突导致的--->

3.

 

SLF4J: Class path contains multiple SLF4J bindings.
SLF4J: Found binding in [jar:file:/D:/ruanjian/apache-maven-3.0.3-NEW/repository/org/slf4j/slf4j-log4j12/1.7.32/slf4j-log4j12-1.7.32.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/D:/ruanjian/apache-maven-3.0.3-NEW/repository/org/apache/logging/log4j/log4j-slf4j-impl/2.14.1/log4j-slf4j-impl-2.14.1.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 [org.slf4j.impl.Log4jLoggerFactory]
log4j:WARN No appenders could be found for logger (org.springframework.boot.ApplicationServletEnvironment).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.

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 :: Spring Boot ::                (v2.5.3)