To decode an event into a sequence of fields, the transport can then call:

The event object is assumed to be a NormalisedEvent instance. It must contain a key of data, which has a value of string type that contains the data to decode. That is, the string contains the line containing the separated data. The codec then decodes the data, and stores the value from each field in a string sequence. This value from each field replaces the value for the data key.

If the event object also contains a sessionId key with an integer value associated with it, the value of the key identifies the configuration the codec uses to interpret the data. If the event does not contain a sessionId, the codec uses the default configuration as specified in the adapter configuration file.