MQSeries.net :: View topic - Problems accessing message tree with dynamic paths

WGerstma · Posted: Mon Jul 18, 2011 1:50 pm Post subject:

Hi,

my real life scenario is very complex, so here a stripped down version of it.

I have a structure coming in via MRM Domain. I want to access elements in this MRM dynamically. The paths to look up elements are coming from outside, be it a user Defined Property or a database table. I thought an easy way to accomplish this was via the {} mechanism.

Here my sample:

<foo>
<bar>
<val1>x</val1>
<val2>y</val2>
</bar>
</foo>

The elements to be accessed are InputRoot.MRM.bar.val1 and InputRoot.MRM.bar.val2.

Here the sample code. With the debugger I can see that c becomes just null:

DECLARE path EXTERNAL CHAR 'bar.val1';

CREATE COMPUTE MODULE foo_Compute
CREATE FUNCTION Main() RETURNS BOOLEAN
BEGIN
DECLARE c CHAR InputBody.{path};
RETURN TRUE;
END;
END MODULE;

When I modify this to:
DECLARE path1 EXTERNAL CHAR 'bar';
DECLARE path2 EXTERNAL CHAR 'val1';

CREATE COMPUTE MODULE foo_Compute
CREATE FUNCTION Main() RETURNS BOOLEAN
BEGIN
DECLARE c CHAR InputBody.{path1}.{path2};
RETURN TRUE;
END;
END MODULE;

In this case the value 'x' is properly assigned to c.

My reallife scenario would have a path hierarchy of 6-10 levels and several other features like the [<] should be supported. Is there any possibility to "inject" the complete path via a single {} or do i have to split the path at the '.' and do terrible things with moving references down the message tree?

JAVA and XPath are both no options to resolve this puzzle.

Any suggestions welcome.