Using the Reference Model
Internally: Enterprise
Systems
Jim Metzger, Harland
Greg Alvord, RealEC
MISMO Trimester Meeting
January 23-27 2012 Jacksonville Florida
The Tasks
• Mapping to Legacy
– Approach
– Tools
• Converting to/from legacy
– XSLT
– Object Model
MISMO Trimester Meeting
January 23-27 2012 Jacksonville Florida
Mapping to Legacy
• Build a spreadsheet
– Lots of people know how
– No way to verify/test
– Artifact disconnected from final process
• Use a tool
– I like Altova Mapforce
• Test map
• Document Map
• Produce XSLT 1.0 , 2.0, Xquery, C#, C++, Java
– Code generation has it own issues.
– Other tools available
MISMO Trimester Meeting
January 23-27 2012 Jacksonville Florida
Converting To/From Legacy
• XSLT -- Map is Data
– Fast to do
– Interpreted or Compiled
– Changes by changing a file (good/bad)
– Unpredictable memory usage
– Can be slow
MISMO Trimester Meeting
January 23-27 2012 Jacksonville Florida
Converting To/From Legacy
• Object Model – Map is compiled code
– Development cycle to do
– Less developer experience available
– Changes by good process
– Known memory model
– Fast!!!!
MISMO Trimester Meeting
January 23-27 2012 Jacksonville Florida
What do Developers Say?
• Developers with relational data
background love MISMO 3.x
– Team background is important
MISMO Trimester Meeting
January 23-27 2012 Jacksonville Florida
What do Developers Say?
• The multidimensionality and repeatability
of sections of the model needs to be well
understood. The repeatability of containers
was a significant change for developers
who had only previously worked in a fixed
length flat file environment.
• People used to 2.x service messages and
flat data models are skeptical.
• Team training in model important.
MISMO Trimester Meeting
January 23-27 2012 Jacksonville Florida
What do Developers Say?
• Legacy systems that reserve memory for
every possible data point have a hard time
with 3.x
– Legacy system using new model
• Needs optional field implementation
– Legacy system using old models
• Middle system filters to data to Legacy
MISMO Trimester Meeting
January 23-27 2012 Jacksonville Florida
What do Developers Say?
• “Floppy-disk syndrome” occurs with
people who coded to Intel 8086 memory
limits and see the big new messages.
– I coded before Floppy Disks and 8086
– Grow with the times
– Train for the times
MISMO Trimester Meeting
January 23-27 2012 Jacksonville Florida
What do Developers Say?
• Best to dedicate a team with the
responsibility of mapping legacy data
models to the new model.
– BA or Developers?
– Both!!
• Crosses legacy management lines.
MISMO Trimester Meeting
January 23-27 2012 Jacksonville Florida
What do Developers Say?
• Provide funding for the effort by applying it
to visible software projects that will
generate revenue.
MISMO Trimester Meeting
January 23-27 2012 Jacksonville Florida
What do Developers Say?
• An internal “global lexicon” became
essential for us, because it insulated the
internal model from MISMO release
changes.
– LDD is a best Practice
– Must digest MISMO releases to internal
needs
MISMO Trimester Meeting
January 23-27 2012 Jacksonville Florida
What do Developers Say?
• The benefits of a single standard do
eventually start to show themselves –
multiple products can talk to multiple thirdparty services after writing one interface.
– SOA is a best practice
– Canonical XML within a the design essential
– MISMO 3.x as Canonical candidate leverages
100 thousand man hours
MISMO Trimester Meeting
January 23-27 2012 Jacksonville Florida
What do Developers Say?
• Developers need to be aware that constraints
and conditions may be placed at both a data
point level and at a container level by the trading
partner. These may be more restrictive than the
MISMO schema. Developers may not be attuned
to thinking about conditionality at a container
level, in addition to a data point level.
– ULDD uses model
– ULDD limits field sizes
– Freddie Mac data constraints different from Fannie Mae
MISMO Trimester Meeting
January 23-27 2012 Jacksonville Florida
What do Developers Say?
• MISMO LDD breaks data into lowest component
pieces. Legacy systems may not store and
process data at the same level of granularity.
This can provide some challenges and require
changes to legacy systems or translation layers
between MISMO and legacy data. Legacy
proprietary code translation into MISMO data
can be complex, actually breaking down into 3
or more MISMO data points.
– Data normalization a best practice
MISMO Trimester Meeting
January 23-27 2012 Jacksonville Florida
What do Developers Say?
• The model may seem overly complex to those
who are implementing to support simpler
business use cases.
– Any use case is a subset of the model.
– MISMO needs to publish the Use Case driven
IGuides
– Yes there are many alternate designs.
– Compatibility across use cases has value. Real
measurable $ and time value.
– If pushed to a simple one off get a blood oath.
• Accountability flows up and down the org chart.
MISMO Trimester Meeting
• NOT just down.
January 23-27 2012 Jacksonville Florida
What do Developers Say?
• There was a steep learning curve on the
concept of Loan States. There was
nothing similar that had existed before, so
working with it the first time was difficult.
Having some MISMO examples of its
usage would have been helpful.
• MISMO needs to publish the Use Case driven
IGuides
MISMO Trimester Meeting
January 23-27 2012 Jacksonville Florida
What do Developers Say?
• Trading partners seem to like the
immediate feedback that a parser provides
letting them know if their file is not wellconstructed which is a plus with the
common MISMO XML.
– Schema validation is good
– Business validation is better
MISMO Trimester Meeting
January 23-27 2012 Jacksonville Florida
What do Developers Say?
• In general, the lack of written materials
explaining the reference model and its
usage was seen as a negative.
Developers are looking for more guidance.
One particular area that was called out
was on the usage of EXTENSIONS.
• MISMO needs to publish the Use Case driven
IGuides
MISMO Trimester Meeting
January 23-27 2012 Jacksonville Florida
What do Developers Say?
• Large number(unmanageable) of objects
share the same namespace when code is
generated…it would be better if the
schema was sub divided a bit more.
– MISMO uses W3C strategy for Namespace
management
– Confusing XML Namespace with Code Namespace.
• Need to be managed differntly
– Arch WG MAY break up the schema more.
MISMO Trimester Meeting
January 23-27 2012 Jacksonville Florida
What do Developers Say?
• Some defined types (like Integer) might be
better as “Int” as they convert to generic
strings when generated
– The xsd:integer issue
– Arch WG to consider solution
MISMO Trimester Meeting
January 23-27 2012 Jacksonville Florida
What do Developers Say?
• Choice Groups when cast into Object
Model need additional code to enforce the
choice on deserialization.
– Deficiency of XSD.EXE?
• May be a missing option setting
MISMO Trimester Meeting
January 23-27 2012 Jacksonville Florida
What do Developers Say?
• Enumerations should have a separate file
– Wants file per enumerated type.
– Arch WG will consider
MISMO Trimester Meeting
January 23-27 2012 Jacksonville Florida
What do Developers Say?
• It would help if a base datatype was
defined so we could extend it as needed
– 3.2 Now has a base type for each data type
– Including enumerated types.
MISMO Trimester Meeting
January 23-27 2012 Jacksonville Florida
Conclusion
• Developers comments positive
• Still some MISMO improvements needed
• MISMO needs to publish the Use Case
driven IGuides
MISMO Trimester Meeting
January 23-27 2012 Jacksonville Florida