I was recently basing some code on the org.apache.cxf.jaxrs.impl.CacheControlHeaderProvider and I noticed that it's handling of the no-cache and private fields isn't quite right.
Current if you have two private fields you would get output like:
If you then parse this back into a CacheControl object it would be interpreted as one private field and an extension directive.
Based on my interpretation of the HTTP 1.1 spec sections:
http://www.w3.org/Protocols/rfc2616/rfc2616-sec2.html#sec2.1 where 1#field is defined as a comma seperated list of one or more fields and
http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.9 where it shows that the list of fields is a optional =, double quote, and a list of fields, and another double quote.
I think the correct output should be:
Cache-Control: private="Field1, Field2"
And of course when parsing a naive splitting based on comma won't work because you have to ignore commas inside the quotes.
I don't think this is a much-used feature of the Cache-Control system or someone would already have reported this problem.