Process the exchange depending on the operation : dir return
the filenames list or the remote directory get return the
remote file with the name specified in the exchange (as attachment or
source, depending on the SU property) mget return all the
remote files put put the message mput put
attachments
Helper class which helps (sic) building SFTPConnectionInfo instance using the
values given in the SU ConfigurationExtensions or using the configuration
node given in a JBI message.