Problem occures when my @BeanParam object has String @HeaderParam values that are null.
On client side inside ClientProxyImpl#getValuesFromBeanParam always returns full Map<String, BeanPair> even when BeanPair has null values.
Methods such handleHeaders, handleCookies has useless condition that is
always true (BeanPair is never null)
That couses unintended behaviour on server side when server receives BeanParam objects with fields with String value equal to "null".
I've sent no headers but servers received header with "null" String.