IMS Connectivity in an On Demand Environment: A Practical Guide to IMS Connectivity

Chapter 13. IMS Connector for Java rerouting and timeout support 259

The DFSYPRX0/DRU0 combination gives you enough flexibility to manage the ALTPCB

output according to your needs. As simple suggestions, you can use DFSYPRX0/DRU0 to:

 Send all your ALTPCB output to a single (or a few) known IMS Connect Tpipe. The

messages get queued in the asynchronous hold queue of that Tpipe, and you could can a

specialized IMS Connector for Java client to retrieve them and send to the final clients.

 Send each ALTPCB output message to an IMS Connect Tpipe, according to the LTERM,

using a different Tpipe for each LTERM. In that case, each of your clients recover the

messages by themselves. Consider the memory requirements of each Tpipe if you choose

this option. The Tpipes use storage, and they do

not free this storage when you stop using

them.

 Send all your ALTPCB output to another OTMA client, such as the IBM WebSphere MQ

IMS bridge, and use any WebSphere MQ client to retrieve the messages.

13.3 Multiple and timed out IOPCB responses

In this section, we discuss the actions you can instruct IMS Connect to take before queuing

the asynchronous messages under their destination Tpipe. Basically, you have the following

choices:

 You can do

nothing, and the messages are discarded.

 You can

discard the messages, so they do not get queued at all.

 You can tell IMS Connect to

reroute the messages, changing the name of the Tpipe where

they will be queued.

The issues discussed in this section do not apply to the ALTPCB inserted messages. We

discuss the management of those messages in 13.2, “Messages inserted to ALTPCB” on

page 258.

13.3.1 Discarding the non-delivered messages

You can ask IMS Connector for Java to purge the asynchronous, undelivered output, setting

the Boolean property purgeAsyncOutput to true. This is a property of the IMSInteractionSpec

object and can be set in different ways, depending on the programming environment you are

using:

 You can set it specifically if you are coding your own Java client using the CCI interface

using the setter setPurgeAsyncOutput of the IMSConnectionSpec class.

 You can use the WebSphere Application Studio Developer Integration Edition or Rational

Application Developer wizards and property sheets to set this value. Figure 13-1 on

page 260 shows the WebSphere Studio Application Developer Integration Edition property

sheet.

260 IMS Connectivity in an On Demand Environment: A Practical Guide to IMS Connectivity

Figure 13-1 WebSphere Studio Application Developer Integration Edition operation property sheet

In any case, you have to be aware of the restrictions summarized in Table 13-1.

Table 13-1 Results of enabling purgeAsyncOutput

Type of message Commit mode 1 Commit mode 0

Shareable connection Shareable connection Dedicated connection

Non-timed out insert to

IOPCB

Ignored Ignored. Runtime exception

Timed out insert to IOPCB The output message is lost.

Because IMS Connector for

Java uses sync

level=NONE, the

transaction is

not rolled

back. The net effect is

equivalent to the message

being purged.

The message is purged. Runtime exception

Second or later insert to

IOPCB by second or later

transaction as result of

program-to-program switch

The message is purged.

The output of second and

later transactions is treated

as commit mode 0.

Non-predictable. See

13.3.2, “Rerouting the

non-delivered messages”

on page 261.

Runtime exception

Insert to IOPCB by a

transaction sent using a

SEND ONLY interaction

Not applicable. The message is

not

purged, but queued under

the system-generated

clientID.

Runtime exception