4 The Energistics Common Package

A key component of the Energistics Common Technical Architecture (CTA) is the Energistics common folder, which contains data objects shared by all Energistics domain standards. Many of these data objects implement requirements from other Energistics specifications. For example, the design of the AbstractObject in common implements requirements from these Energistics specs: Identifier, EIP, and Unit of Measure.

For more information, see the Energistics common Technical Reference Guide.

Additionally, each domain standard has its own common folder (i.e., WitsmlCommon, ResqmlCommon and ProdmlCommon), which provides consistency required for that particular domain. So domain data objects inherit from their domain common, and then from Energistics common.

Figure 4-1 shows the UML model of the common package, which is used to generate the XSD files. This chapter is organized by the order of the packages in the figure.

This chapter describes how the data objects in Energistics common package are intended to work when a domain standard is implemented in software. Classes and attributes defined in the UML model are converted into XML elements, types, and attributes in the resulting XML schema (XSD file), from where programmers can use proxy generators to create classes in their development environments. Because behavior is not specifiable in XML, the operations part of the class boxes is not used, and the UML model does not hold methods.

The resulting XSDs for Energistics common are included when you download any of the Energistics domain standards.

Figure 4-1 Each Energistics domain standard references the Energistics common folder, which contains shared data objects of the Energistics CTA. This screen shot shows common with the WITSML model.