Unable to start ServletWebServerApplicationContext due to missing ServletWebServerFactory bean.

1、Unable to start ServletWebServerApplicationContext due to missing ServletWebServerFactory bean.

缺少依赖  加上依赖就行

    org.springframework.boot
    spring-boot-starter-web

2、Reason: No converter found capable of converting from type [java.lang.String] to type [java.lang.Class]

引入阿里数据源

        
            com.alibaba
            druid-spring-boot-starter
            1.1.13
        
        
            com.alibaba
            fastjson
            1.2.47
        

3、Caused by: java.lang.ClassNotFoundException: com.mysql.cj.jdbc.Driver

这个是没有mysql连接驱动，把驱动加上就行，这里推荐阿里云的mvn搜索

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