This package contains all the headers interfaces supported by this specification. SIP header fields are similar to HTTP header fields in both syntax and semantics. This specification models each SIP header as a specific interface as opposed to have a single generic interface to handle all header information. It is deemed more explicit for protocol support to define protocol characteristics as opposed to generic interfaces. This specification supports all the headers defined in RFC 3261 and other headers introduced by supporting the following additional RFC's:
This specification also provides a mechanism to support other extension Headers. If a SIP stack vendor supports such extension headers these must extend the ExtensionHeader interface, which contains header name and header value attributes.
Additionally this package contains a HeaderFactory class that defines methods for creating new headers. The HeaderFactory is a singleton object, which can be obtained from the {@link javax.sip.SipFactory}.