MQSeries.net :: View topic - backout not reinstating messages on the queue

OEvans · Posted: Wed Sep 25, 2002 5:25 pm Post subject:

I written a java class that, among other things, attempts to retreive a group of message from a queue. Getting the group works fine but if there is a problem and I try to backout I have noticed the the messages I have pulled off of the queue are not reinstated back onto the queue. This is my first crack at MQSeries programming so I assume I am not understanding something. Can anyone explain why, after I call backout(), the messages I got are still missing from the queue? Am I just not understanding the purpose of backout properly?

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code
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public MQMessage[] getMessageGroup()
throws MQException, IOException
{
int openOptions = MQC.MQOO_INPUT_AS_Q_DEF | MQC.MQOO_FAIL_IF_QUIESCING;
MQQueue queue = queueMgr.accessQueue(queueName, openOptions, null, null, null);
Vector msgGroup = new Vector();

MQGetMessageOptions getOptions = new MQGetMessageOptions();
getOptions.options = getMessageOptions +
MQC.MQGMO_SYNCPOINT +
MQC.MQGMO_WAIT +
MQC.MQGMO_ALL_MSGS_AVAILABLE +
MQC.MQGMO_LOGICAL_ORDER;

getOptions.matchOptions = MQC.MQMO_MATCH_GROUP_ID;

try {
while(true){
MQMessage incoming = new MQMessage();
queue.get(incoming, getOptions);
msgGroup.add(incoming);
char x = getOptions.groupStatus;
if (x == MQC.MQGS_LAST_MSG_IN_GROUP){
break;
}

int groupSize = msgGroup.size();
MQMessage[] messages = new
MQMessage[groupSize];

msgGroup.copyInto(messages);

queueMgr.commit();
queue.close();
return messages;
} catch (MQException mqex){
queueMgr.backout();
}

return null;
}