现象

程序启动是报错

16:58:47.845 ERROR 11524 --- [           main] o.s.b.d.LoggingFailureAnalysisReporter   : 

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APPLICATION FAILED TO START
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Description:

A component required a bean of type 'xxx' that could not be found.

The following candidates were found but could not be injected:
	- xxx resulted in false


Action:

Consider revisiting the entries above or defining a bean of type xxx in your configuration.

Disconnected from the target VM, address: '127.0.0.1:51851', transport: 'socket'

Process finished with exit code 1

分析

未找到需要引用的类

解决方案

1. 确认pom中引入了该类jar包；
2. Spring初始化是否会扫描该类所在的目录，非启动目录可以使用ComponentScan加入启动扫描；
3. Spring是否对该类实现进行了初始化加载，实现类上是否使用了Component、Service等初始化加载标签。