Copyright © 2013 Open Geospatial Consortium.
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7.3.3 UML Templates for SWE Data Streams and Data Records 7.3.3.1 Scope
The OWS-9 GPS study has been developing templates for SWE Common 2.0 data streams and records. As these templates are in a way also the result of a modeling
activity, it might be of value to explore if and how UML could be used to describemodel such templates, too. At the moment, the records are usually modeled directly as XML
instances.
This subject was originally not planned to be addressed in OWS-9 and as a result could only be explored on a general level. A sample data stream from the GPS study, the
MSNCC-EPOCHA Data Stream, has been modeled in UML. The template as developed in XML is included as Annex B.
7.3.3.2 UML Profile and Mapping
A UML profile has been specified to allow modeling the different aspects of the sample data stream template in UML. The profile and mapping is described in
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Table 6. The Enterprise Architect XML file of the profile is included in Annex C. Before defining a new profile, an attempt was made to use consider such data stream
templates as application schemas according to ISO 19109 and model them according to the existing UML profile for application schemas. However, a model with sufficient
information to convert it to SWE Common data components requires a significant amount of additional information and thus requires extensions to the UML profile in any
case. Another aspect is that instead of a metamodel for features like the General Feature Model from ISO 19109, we are essentially using a different metamodel for SWE
Common data components. We could have added all the necessary information as tagged values only instead of defining new stereotypes, but have opted to use stereotypes
to link the concepts to the underlying SWE Common metamodel in a clearer way.
The MSNCC-EPOCHA stream modeled in UML using this profile is shown in Figure 8. The SWE Common XML encoding of the MSNCC-EPOCHA Data Stream template
could be derived automatically from the UML model of the data stream. Of course, this is only an example and more a complete mapping a more in-depth analysis and testing
would be required.
