Intercepting based on HTTP header in RESTeasy
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I am developing REST services with two types.

 - before login no session token will be passed to HTTP header.
 - after login session token will be passed in each request.

I dont want to include @HeaderParam in each and every REST method. I want to intercept it first and based on that I want to check the validity of session. Please let me know 

 1. how I can intercept only headers in RESTEasy
 2. How to avoid intercepting few methods

Thanks.