How to encode msgKey attribute in RFA Java

@Catherine Wong

According to the document (<RFA_PACKAGE>/Docs/refman/rfajava/com/reuters/rfa/omm/OMMEncoder.html), if the application wants to encode attrib, it must not specify the second parameter as OMMTypes.NO_DATA.

encodeMsgInit
void encodeMsgInit(OMMMsg msg,
                   short attibDataType,
                   short dataType)

OMMMsg encoding initialization


Parameters:

msg - the message to be encoded.

attibDataType - the data type that is contained in the OMMAttribInfo. OMMTypes.NO_DATA if encoded OMMAttribInfo will not contain OMMData (i.e. OMMAttribInfo.getAttrib()).

dataType - the data type that is contained in the message. OMMTypes.NO_DATA if encoded message will not contain data.

Referring to RFA Java RDM Usage guide, OMMAttribInfo.Attrib is not used in most of domains except a Login domain.

Since the RFA example applications usually manage the administrative domain (Login, Source Directory, and Dictionary) automatically, you can find the simple demonstration from a LoginClient.encodeLoginReqMsg() method of a StarterConsumer example.

Please see the snippet code below:

    private OMMMsg encodeLoginReqMsg()
    {
        OMMEncoder encoder = _mainApp.getEncoder();
        OMMPool pool = _mainApp.getPool();
        encoder.initialize(OMMTypes.MSG, 500);
        OMMMsg msg = pool.acquireMsg();
        msg.setMsgType(OMMMsg.MsgType.REQUEST);
        msg.setMsgModelType(RDMMsgTypes.LOGIN);
        msg.setIndicationFlags(OMMMsg.Indication.REFRESH);
        msg.setAttribInfo(null, CommandLine.variable("user"), RDMUser.NameType.USER_NAME);


        encoder.encodeMsgInit(msg, OMMTypes.ELEMENT_LIST, OMMTypes.NO_DATA);
        encoder.encodeElementListInit(OMMElementList.HAS_STANDARD_DATA, (short)0, (short)0);
        encoder.encodeElementEntryInit(RDMUser.Attrib.ApplicationId, OMMTypes.ASCII_STRING);
        encoder.encodeString(CommandLine.variable("application"), OMMTypes.ASCII_STRING);
        encoder.encodeElementEntryInit(RDMUser.Attrib.Position, OMMTypes.ASCII_STRING);
        encoder.encodeString(CommandLine.variable("position"), OMMTypes.ASCII_STRING);
        encoder.encodeElementEntryInit(RDMUser.Attrib.Role, OMMTypes.UINT);
        encoder.encodeUInt((long)RDMUser.Role.CONSUMER);
        encoder.encodeAggregateComplete();


        // Get the encoded message from the encoder
        OMMMsg encMsg = (OMMMsg)encoder.getEncodedObject();


        // Release the message that own by the application
        pool.releaseMsg(msg);


        return encMsg; // return the encoded message
    }

Below is an application log:

MESSAGE
	Msg Type: MsgType.REQUEST
	Msg Model Type: LOGIN
	Indication Flags: REFRESH
	Hint Flags: HAS_ATTRIB_INFO
	AttribInfo
		Name: U0154418
		NameType: 1 (USER_NAME)
		Attrib
			ELEMENT_LIST
				ELEMENT_ENTRY ApplicationId: 256
				ELEMENT_ENTRY Position: 10.42.85.159/U0154418-TPL-A
				ELEMENT_ENTRY Role: 0
	Payload: None

Hope this helps!