Correct the classpath of your application so that it contains a single, compatible version of org...

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日志出现警告：
WARN org.springframework.boot.web.servlet.context.AnnotationConfigServletWebServerApplicationContext -Exception encountered during context initialization - cancelling refresh attempt: org.springframework.context.ApplicationContextException: Failed to start bean 'documentationPluginsBootstrapper'; nested exception is java.lang.NoSuchMethodError: org.springframework.plugin.core.PluginRegistry.getPluginFor(Ljava/lang/Object;Lorg/springframework/plugin/core/Plugin;)Lorg/springframework/plugin/core/Plugin;

发现原来是因为引入了swagger2，
今早spring更新了jar包

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删除了里面的某些方法getPluginFor，导致的。
删除pom引入，启动成功。