How to get specific message and only delete that from the queue

Question

I have a requirement to get just a specific message from a queue based on its correlation ID.

Is there a way where we can get a message for the corresponding correlation ID and remove only that message from the queue without deleting the others.

The options which I have tried they retrieve the message but removing the other messages from the queue as well while finding my message

I have used the following openOptions in accessQueue method while browsing the queue

MQC.MQOQ_INPUT_SHARED | MQC.MQOO_FAIL_IF_QUIESCING | MQC_MQOO_INQUIRE | MQC.MQOOBROWSE

And the following options to get the message

    String correlation ID = <correlationID>

    MQMessage respMessage = new MQMessage();

    respMessage.correlationId = correlation ID.getBytes();

    MQGetMessageOptions msg = new MqGetMessageOptions();    
    msg.options = MQC.MQGMO_NO_WAIT + MQC.MQGMO_FAIL_IF_QUIESCING + MQC.MQGMO_CONVERT + MQC.MQGMO_BROWSE_NEXT

        msg.matchOptions = MQC.MQMO_MATCH_MSG_ID

msg.waitInterval = 2000;

queue.get(respMessage, msg);

Answer 1

You have many issues with your code.

(1) As Morag said, remove the MQGMO_BROWSE_NEXT option if you want to remove the message from the queue (i.e. destructive get).

respMessage.correlationId = correlation ID.getBytes();
msg.matchOptions = MQC.MQMO_MATCH_MSG_ID

(2) You are setting the CorrelId but then requesting to match on MsgId. That won't work. You will get reason code of MQRC_NO_MSG_AVAILABLE (2033).

(3) MsgIds and/or CorrelIds should never be converted to a string or start as a string. MsgIds and/or CorrelIds will contain binary data. Hence, MsgIds and CorrelIds should always be a byte array. i.e. byte[]

Here is a screenshot of a message's MsgId and CorrelId:

(4) You have MQGMO_NO_WAIT option but you set waitInterval to 2000. If you want to wait for up to 2 seconds for a message to arrive then you need to use the MQGMO_WAIT option.

MQGetMessageOptions msg = new MqGetMessageOptions();

(5) "msg" is a terrible variable name. It will only confuse people because they will think it references a message. i.e. MQMessage class. It is far better to call the variable "gmo".

i.e.

MQGetMessageOptions gmo = new MqGetMessageOptions();
gmo.options = CMQC.MQGMO_WAIT + CMQC.MQGMO_FAIL_IF_QUIESCING + CMQC.MQGMO_CONVERT;
gmo.waitInterval = 2000;
gmo.matchOptions = CMQC.MQMO_MATCH_CORREL_ID;