When in the integration of DRUID based springBoot frame configuration corresponding ServletRegistrationBean in DruidConfig class configuration, the path does not accidentally filled out / druid / **, leading to local access, you can not jump DRUID monitoring the landing page but reported a 404 error, when was later revised to / druid / *, you can access the login page, so in this path to explore the differences in SpringBoot framework / * and / ** based on.
# When the path is / druid / **, to access page 404
# When the path is / druid / **, to access the page druid landing page
Therefore, in this talk about the difference between / * and / ** are
