spring-boot 将默认的logback替换为log4j2启动报错

今天启动项目时提示失败，失败日志如下：

Exception in thread "main" java.lang.IllegalArgumentException: LoggerFactory is not a Logback LoggerContext but Logback is on the classpath. Either remove Logback or the competing implementation (class org.apache.logging.slf4j.Log4jLoggerFactory loaded from file:/C:/Users/86186/.m2/repository/org/apache/logging/log4j/log4j-slf4j-impl/2.10.0/log4j-slf4j-impl-2.10.0.jar). If you are using WebLogic you will need to add 'org.slf4j' to prefer-application-packages in WEB-INF/weblogic.xml: org.apache.logging.slf4j.Log4jLoggerFactory
	at org.springframework.util.Assert.instanceCheckFailed(Assert.java:637)
	at org.springframework.util.Assert.isInstanceOf(Assert.java:537)
	at org.springframework.boot.logging.logback.LogbackLoggingSystem.getLoggerContext(LogbackLoggingSystem.java:274)
	at org.springframework.boot.logging.logback.LogbackLoggingSystem.beforeInitialize(LogbackLoggingSystem.java:99)
	at org.springframework.boot.context.logging.LoggingApplicationListener.onApplicationStartingEvent(LoggingApplicationListener.java:191)
	at org.springframework.boot.context.logging.LoggingApplicationListener.onApplicationEvent(LoggingApplicationListener.java:170)
	at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:172)
	at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:165)
	at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:139)
	at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:127)
	at org.springframework.boot.context.event.EventPublishingRunListener.starting(EventPublishingRunListener.java:68)
	at org.springframework.boot.SpringApplicationRunListeners.starting(SpringApplicationRunListeners.java:48)
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:313)
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1255)
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1243)
	at com.ooomap.user.OooMapUserApplication.main(OooMapUserApplication.java:27)
Disconnected from the target VM, address: '127.0.0.1:59593', transport: 'socket'

1.分析日志
从日志报错的信息可以看出是因为class path中引入了Logback,但在项目中使用的LoggerFactory 并不是logback中的，导致日志加载失败
2.查找项目中的依赖
使用idea查找依赖


按住ctrl+鼠标滚轮将其放大，然后按ctrl+f 查找logback


选中箭头指向logback的线条，找到依赖logback的jar,从图中可以看出是play-core中依赖了logback,然后依次往上查找，最后发现是阿里云的大于中的依赖了loback



3.排除依赖
使用exclusion将其依赖的logback移除

<dependency>
            <groupId>com.airlenet</groupId>
            <artifactId>play-aliyun-dysms</artifactId>
            <version>${play-aliyun-dysms.version}</version>
            <exclusions>
                <exclusion>
                    <groupId>commons-logging</groupId>
                    <artifactId>commons-logging</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>ch.qos.logback</groupId>
                    <artifactId>logback-classic</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>com.google.guava</groupId>
                    <artifactId>guava</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

4.启动项目

心得：使用google和baidu搜索的结果很多都不是自己想要的答案，
每个人出现错误的环境也不同，只有自己通过分析查找到问题的根本原因，才能对自己有所提升。很多时候我们一出现问题连看不都不看就直接去搜索答案，这就会形成一种依赖，当没有这些搜索工具的时候，我们就无法去分析和解决问题。