@mutex and @dev aren't available on jruby so it fails when called.
NoMethodError: undefined method `synchronize' for nil:NilClass
write at /usr/local/bundle/gems/logger_facade-0.4.1/lib/logger_facade/plugins/logstash.rb:57
log at /usr/local/bundle/gems/logger_facade-0.4.1/lib/logger_facade/plugins/logstash.rb:41
info at /usr/local/bundle/gems/logger_facade-0.4.1/lib/logger_facade/plugins/base.rb:26
block in log at /usr/local/bundle/gems/logger_facade-0.4.1/lib/logger_facade/log.rb:42
each at org/jruby/RubyArray.java:1734
log at /usr/local/bundle/gems/logger_facade-0.4.1/lib/logger_facade/log.rb:41
info at /usr/local/bundle/gems/logger_facade-0.4.1/lib/logger_facade/log.rb:25
@mutex
and@dev
aren't available on jruby so it fails when called.