How to convert from a Dead Letter to a BytesMessage in Java using MQ Classes (IBM)

Question

I want to resend a Message from a Dead Letter Queue. For that, I need to convert the Dead Letter to a BytesMessage (Payload could be a ZIP or a String).

What I tried so far:

Get RFH2 by MQRFH2 class and seek():

        mqMessage.seek(0); MQRFH2 rfh2 = new MQRFH2(mqMessage); byte[]
        data = new byte[mqMessage.getDataLength()];
        mqMessage.readFully(data); System.out.println("Message data: "
        +new String(data));.

Get RFH2 by MQHeaderlist:

        MQHeaderList list = new MQHeaderList (mqMessage, true); // Step 1.
        MQDLH dlh = (MQDLH) list.get (0); // Step 2.
        int reason = dlh.getReason (); // Step 3.
        list.remove (dlh); // Step 4.
        mqMessage = new MQMessage ();
        list.write (mqMessage, true); // Step 5.
        mqMessage.format = list.getFormat (); // Step 6.

        MQHeaderIterator it = new MQHeaderIterator(mqMessage);

        while (it.hasNext()) {
            MQHeader header = it.nextHeader();

            System.out.println("Header type " + header.type() + ": " + header);
        }

Get RFH2 by MQRFH2 class:

        MQHeader header = new MQRFH2(mqMessage);
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        header.write(new DataOutputStream(out), CMQC.MQENC_NATIVE,
        CMQC.MQCCSI_DEFAULT); byte[] bytes = out.toByteArray(); String
        sout = new String(bytes); System.out.println(sout);

Nothing worked for me: I get errors, like this one:

MQJE001: Beendigungscode '2', Ursache '6114'.
MQJE001: Beendigungscode '2', Ursache '2195'.
ch.coop.mid.hecol.DAEQHandler.exception.ZDAEQException: com.ibm.mq.headers.MQDataException: MQJE001: Beendigungscode '2', Ursache '2195'.
    at ch.coop.mid.hecol.DAEQHandler.bl.impl.ZMQQueueImpl.resendAllLetters(ZMQQueueImpl.java:52)
    at ch.coop.mid.hecol.DAEQHandler.ZStart.main(ZStart.java:20)
Caused by: com.ibm.mq.headers.MQDataException: MQJE001: Beendigungscode '2', Ursache '2195'.
    at com.ibm.mq.headers.MQDataException.getMQDataException(MQDataException.java:316)
    at com.ibm.mq.headers.internal.Header.read(Header.java:620)
    at com.ibm.mq.headers.MQRFH2.<init>(MQRFH2.java:113)
    at ch.coop.mid.hecol.DAEQHandler.dto.ZMessageDTO.<init>(ZMessageDTO.java:60)
    at ch.coop.mid.hecol.DAEQHandler.bl.impl.ZMQQueueImpl.resendAllLetters(ZMQQueueImpl.java:50)
    ... 1 more
Caused by: com.ibm.mq.headers.MQDataException: MQJE001: Beendigungscode '2', Ursache '6114'.
    at com.ibm.mq.headers.MQDataException.getMQDataException(MQDataException.java:313)
    at com.ibm.mq.headers.MQRFH2.read(MQRFH2.java:184)
    at com.ibm.mq.headers.internal.Header.read(Header.java:639)
    at com.ibm.mq.headers.internal.Header.read(Header.java:617)
    ... 4 more
Caused by: java.io.EOFException: MQJE086: Ausnahmebedingung durch Dateiende ('MQMessage.seek()').
    at com.ibm.mq.MQMessage.seek(MQMessage.java:715)
    at com.ibm.mq.headers.internal.store.MQMessageStore.readFrom(MQMessageStore.java:274)
    at com.ibm.mq.headers.internal.Header.read(Header.java:661)
    at com.ibm.mq.headers.MQRFH2.read(MQRFH2.java:181)

Is there another way to convert a Dead Letter to a BytesMessage without splitting the whole messages in to little parts an assembling them back together? This way is not very beautiful for my opinion. It's very unstable.

EDIT: I can only use the version 7.5.0.0 of the mq libraries in java.

Why are you not using the dead letter handler to resend messages? You can set up rules to retry, forward, etc. See these 2 links for more info http://www.ibm.com/support/knowledgecenter/SSFKSJ_7.5.0/com.ibm.mq.pla.doc/q005540_.htm http://www.ibm.com/support/knowledgecenter/SSFKSJ_7.5.0/com.ibm.mq.ref.adm.doc/q083420_.htm — ValerieLampkin, Jun 23 '16 at 19:33
Because I need to solve the "problem" with a java application. @ValerieLampkin — toxerli, Jul 11 '16 at 11:18

score 1 · Accepted Answer · answered Jun 24 '16 at 16:00

What in the world are you doing? You seem like you are attacking the problem backwards. The message layout is MQDLH + MQRFH2 + message data.

I'll assume you want to resend the "MQRFH2 + message data" to the original destination queue.

Here is how your code should look:

mqMsg.seek(0);
MQDLH dlh = new MQDLH(mqMsg);
System.out.println("Reason code= "+dlh.getReason() + " : Dest. Queue Name="+dlh.getDestQName());

byte[] bData = new byte[mqMsg.getDataLength()];
mqMsg.readFully(bData);

// Open the original destination queue
int openOutputOptions  = CMQC.MQOO_OUTPUT + CMQC.MQOO_FAIL_IF_QUIESCING;
MQQueue outQ = _qMgr.accessQueue( dlh.getDestQName().trim(),
                                  openOutputOptions,
                                  dlh.getDestQMgrName().trim(),
                                  null,
                                  null );

// Create a new message and set the values from DLH
MQMessage newMsg = new MQMessage();
newMsg.characterSet = dlh.getCharacterSet();
newMsg.encoding     = dlh.getEncoding();
newMsg.format       = dlh.getFormat();

newMsg.write(bData);  // write the data

MQPutMessageOptions pmo = new MQPutMessageOptions();
pmo.options =  CMQC.MQPMO_FAIL_IF_QUIESCING;

// Put the message to the destination queue
outQ.put(newMsg, pmo);

outQ.close();

But this doesn't copy the MQMD or other headers?` – toxerli Jul 11 '16 at 06:16 — toxerli, Jul 11 '16 at 06:16

How to convert from a Dead Letter to a BytesMessage in Java using MQ Classes (IBM)

1 Answers1