Tries to read a Context entry from the medium.
Tries to read a Context entry from the medium. If a Context entry is successfully read, implementations must return an updated Context instance that includes such entry. If no entry could be read simply return the Context instance that was passed in, unchanged.
Tries to write an entry from the provided Context into the medium.
Tries to write an entry from the provided Context into the medium.
Reads and Writes a Span instance using the B3 propagation format. The specification and semantics of the B3 Propagation format can be found here: https://github.com/openzipkin/b3-propagation