MQ Adapter and the use of correlation Ids

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1

The issue I am having with the above is my test harness is sending an MQ message to an Wm Q listener. A document is created from the message body which includes the MsgId and CorrelId and is published to a broker. A subscriber receives the document and moves the MsgId to the CorrelId field so that the client can match the reply with the request. The problem is that the CorrelId on the reply message in the client is not always matchable with the MsgId originally sent and I can’t figure out why. There is a variation between the MsgId sent and the CorrelId received. It is apparent that the CorrelId received is based on the original MsgId but is slightly changed.

Outbound
MsgId 414D512042524C54383537383320202052 -->8986<-- 3F20000501

Inbound
CorrelId 414D512042524C54383537383320202052 -->3F3F<-- 3F20000501

It may well be the way I am configuring MQ but I can’t be sure as sometimes it is fine.

MsgId as displayed in the testharness GUI on client
414D512042524C5438353738332020205289863F20000501

MsgId displayed in webMethods IS by custom java Service prior to publish
and. Same is displayed by subscriber.
414D512042524C5438353738332020205289863F20000501

CorelId as displayed in the MQ console GUI on webMethods host
414D51204349533030322020202020201E4F783F32620800

CorrelId as displayed in browsing the MQ queue using amqsbcg on client
414D512042524C543835373833202020523F3F3F20000501

When it does work it seems that if the CorrelId ends in 3F
(for example: 414D512042524C5438353738332020205289863F2000053F)
It seems to cause 12 of the following messages to have CorrelIds generated by the MQ server on the Wm host which bear no relation to the MsgIds sent and are consequently not matchable.

I am running webMethods IS 6.0.1 on Windows 2000, Version 3.0 of the MQ Adapter and version 5.3 of MQ on both testharness client and IS hosts and have remote queues and channels between them.

Can anyone help?

2

Pat,
I don’t know if this will address your issue. I was having trouble with a custom java service converting msgidbytes to hex. In some instances Java was returning a negative number (-119) instead of its positive counterpart (137). The code was changed to:
for (int b = 0 ; b < msgidbytes.length ; b++)
{
int i = msgidbytes[b];
if (i < 0) i = 256 + i; // ← added this line
…

Where it would add 256 to the negative that was returned to get the positive representation.

Stan

3

Hi Stan,

Thanks for the help. I too use a custom Java service but it seems to work ok and has no side effects. I have enquired and have been instructed not to use CorrelId but to use the CorrelationIdByteArray and have just posted another message to do with this entitled the MQAdapter and the msgHeader.

Thanks
Pat

4

I am facing a similar situation can you please specify how this was resolved?
Thanks so much…
Harsh

5

Hi Pat,

did you fix your problem ??
if ok, so please tell me how you did with more explanation

Thanks in advance