Re: xml ==> db2/400

["David Morris" <David.Morris@xxxxxxxxxxxxx>]

Keith,

JDOM will be very slow for what you are trying to accomplish. Are you
just
trying to add some logging to see how long this is taking? For logging
I
like to use the Jakarta Commons logging interfaces. There is a simple
log
implementation that writes to the console. With the simple log, you
could
just include time in the output message and log something like "start
of
load", and "end of load".

I wrapped the Jakarta commons logging in a single static class that
makes
it easier to use on the AS/400. I also created a log implementation
that
writes logging messages to the joblog. Here is something I wrote up on

how to use this:

http://www.midrangeserver.com/mgo/mgo100402-story02.html

You can download the source from CVS at SourceForge. There is one
additional class I added after the article was published. It is:

http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/iseries-toolkit/iseries-toolkit/src/java/org/iseriestoolkit/util/DefaultLog.java?rev=HEAD&content-type=text/vnd.viewcvs-markup

David Morris

>>> keith_mccully@wunderman.co.uk 12/17/02 08:33AM >>>
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I had a requirement to convert a 25,000 customer detail element xml
into
an iSeries PF. Each element had around 2.5 Kb data and a total of
nearly
60 Mb. The xml structure is flat, ie customer detail element has no
sub
elements, just attributes :
<custdata atr1="val1" atr2="val2" .........atrN="valN"  />. Each
customer
element converts to a PF record and each attribute to a PF column.

My preferred choice would be to use JDOM as it's straightforward to
code
and great for random access to the DOM tree. However  the whole DOM
tree
is loaded into memory and given the volume of data this will raise
performance issues. Instead, I chose the SAX  APIs from the Xerces
parser.
Since, SAX  uses event driven processes which are ideal for a straight
through read of the xml document and will not load the whole document
into
memory so avoiding the performance issues.

With SAX the whole parse/load process took about 2.5 minutes on an 830
machine which was good. I would liked to have run a JDOM load for a
comparison but didn't have time although I suspect that it would take
much
longer.

Just 1 question. Is there any restriction or scoping as to what can be
called from the ContentHandler methods against ordinary methods? I
instantiated the Date class in the startDocument method to a member
level
variable and then did t oString() to print the start time:
        d = new Date();
        System.out.println(d.toString());
This printed OK but when I did  System.out.println(d.toString());  to
print the end time in the endDocument method I got a null exception on
reference d. I expected this to work since d was a member variable.
Does
anyone the cause of this and a workaround other than a second Date
instantiation.

Thanks,

Keith