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For using the data model generation, use the dmgen-maven-dmgen-plugin. The data model is specified in a datamodel specification xml file, usually called datamodel.xml. Its location is given by the parameter dmSpecFile of the dmgen-maven-dmgen-plugin. Based on that file, the generator can generate various kinds of source code. The decision what to generate is given in a configuration file, usually called generator.xml. Its location is given by the parameter dmConfigFile of the dmgen-maven-dmgen-plugin.
A common usecase is having the datamodel.xml file in the api project, and using it for generation both in the api and in the impl project, with a generator.xml in both projects. To make this work, one must include the datamodel.xml file into the api bundle as a resource, and then refer to it from the impl bundle.
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