关于解决springboot : java.lang.NoClassDefFoundError: ch/qos/logback/core/joran/spi/JoranException启动报错问题

Spring Boot 2.0.4 启动报错：

Failed to instantiate SLF4J LoggerFactory
Reported exception:
java.lang.NoClassDefFoundError: ch/qos/logback/core/joran/spi/JoranException
    at org.slf4j.LoggerFactory.bind(LoggerFactory.java:150)
    at org.slf4j.LoggerFactory.performInitialization(LoggerFactory.java:124)
    at org.slf4j.LoggerFactory.getILoggerFactory(LoggerFactory.java:412)
    at org.slf4j.LoggerFactory.getLogger(LoggerFactory.java:357)
    at org.apache.logging.slf4j.SLF4JLoggerContext.getLogger(SLF4JLoggerContext.java:39)
    at org.apache.commons.logging.LogFactory$Log4jLog.<init>(LogFactory.java:204)
    at org.apache.commons.logging.LogFactory$Log4jDelegate.createLog(LogFactory.java:166)
    at org.apache.commons.logging.LogFactory.getLog(LogFactory.java:109)
    at org.apache.commons.logging.LogFactory.getLog(LogFactory.java:99)
    at org.springframework.boot.SpringApplication.<clinit>(SpringApplication.java:200)
    at com.wangp.springboot.quickstart.SpringBoot02QuickstartApplication.main(SpringBoot02QuickstartApplication.java:13)
Caused by: java.lang.ClassNotFoundException: ch.qos.logback.core.joran.spi.JoranException
    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    ... 11 more
Exception in thread "main" java.lang.NoClassDefFoundError: ch/qos/logback/core/joran/spi/JoranException
    at org.slf4j.LoggerFactory.bind(LoggerFactory.java:150)
    at org.slf4j.LoggerFactory.performInitialization(LoggerFactory.java:124)
    at org.slf4j.LoggerFactory.getILoggerFactory(LoggerFactory.java:412)
    at org.slf4j.LoggerFactory.getLogger(LoggerFactory.java:357)
    at org.apache.logging.slf4j.SLF4JLoggerContext.getLogger(SLF4JLoggerContext.java:39)
    at org.apache.commons.logging.LogFactory$Log4jLog.<init>(LogFactory.java:204)
    at org.apache.commons.logging.LogFactory$Log4jDelegate.createLog(LogFactory.java:166)
    at org.apache.commons.logging.LogFactory.getLog(LogFactory.java:109)
    at org.apache.commons.logging.LogFactory.getLog(LogFactory.java:99)
    at org.springframework.boot.SpringApplication.<clinit>(SpringApplication.java:200)
    at com.wangp.springboot.quickstart.SpringBoot02QuickstartApplication.main(SpringBoot02QuickstartApplication.java:13)
Caused by: java.lang.ClassNotFoundException: ch.qos.logback.core.joran.spi.JoranException
    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    ... 11 more

分析：

是找不到相关类导致的错误，那么根据错误原因，pom.xml导入相关依赖：

       <dependency>
            <groupId>ch.qos.logback</groupId>
            <artifactId>logback-core</artifactId>
        </dependency>

版本不用指定，父依赖中有指定。

再次启动，一切正常。

 

但是关于这个错误，有一个疑问，就是Spring boot 2.0.4在我同事电脑上运行时，不用添加这个依赖，依然能够正常启动，这点事有点莫名其妙的。目前还不知道具体原因，希望有一天有大神能够帮忙解答吧。