Parsing custom Tomcat access log


I have the following log line from tomcat access log: ( - USER123 [23/Mar/2015:00:00:12 +0000] GET /rest/url/v1/state?appStateOnly=true HTTP/1.1 200 111 7 rest.api.package:443 ( - USER124 [23/Mar/2015:00:00:13 +0000] GET /rest/ping HTTP/1.1 200 23 177 ( - USER003 [23/Mar/2015:00:00:14 +0000] GET /rest/url/v1/state?appStateOnly=true HTTP/1.1 200 111 6 rest.api.package:443

I've tried different examples out in the internet, is there a simple way to parse the above values?
I run Logstash v. 2.3.

Need a bit of help getting past this issue. Thanks!

Providing some examples of what you have tried may be useful for others to help you.

I was going to handle those string as csv-file, separating it on the whitespaces. It still looks for the best parsing example to me.

Apart the solution mentioned above, I found and, which is easy to develop the regex pattern