If both the servlet container and a web application use SLF4J,
ServiceLoader calls are susceptible to three problems:

1. The SLF4J copy in the webapp detects the common providers by can not
   instantiate them (they implement a different copy of
   SLF4JProviderService),
2. The SLF4J copy in the common classloader can bind the providers in
   the webapp classloader and cause a memory leak,
3. If the server uses a SecurityManager the static initialization of
   LoggerFactory fails if called by unprivileged code.