排除spring-boot-starter-web中的日志回传依赖项会阻止log4j系统正确初始化

Question

SLF4J: Class path contains multiple SLF4J bindings.
SLF4J: Found binding in [jar:file:/C:/Users/.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:/C:/Users/.m2/repository/ch/qos/logback/logback-classic/1.2.3/logback-classic-1.2.3.jar!/org/slf4j/impl/StaticLoggerBinder.class]

以下是排除日志时遇到的问题：

log4j:WARN No appenders could be found for logger (org.springframework.web.context.support.StandardServletEnvironment).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.

以下是排除slf4j-log4j时的错误：

Exception in thread "main" java.lang.AbstractMethodError: org.springframework.boot.context.config.ConfigFileApplicationListener.supportsSourceType(Ljava/lang/Class;)Z

Answer 1

为什么您认为日志是一个依赖项？

Logback直接实现slf4j，您通过sl4j api使用Logback，因此您的代码永远不会依赖于Logback，但它可能依赖于slf4j。

您在此概述的问题：

log4j:WARN No appenders could be found for logger (org.springframework.web.context.support.StandardServletEnvironment).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.