SEVERE: Context initialization failed
org.springframework.beans.factory.BeanCreationException: Error creating bean with name '_authenticationManager': Invocation of init method failed; nested exception is java.lang.IllegalArgumentException: No authentication providers were found in the application context
OK, it looks like you are using Spring Security. In that you are required for defining an AuthenticationProvider/UserDetailsService to load your user data. Since every app uses something different, it will be specific to your application. But you have to define a bean for it.