Integrations (PTC products, 3rd party products and code) > Code integration (Ada, ARINC 653, C, C#, C++, IDL, Java, SQL and VB) > Transformation Development Kit (TDK) > Customizing an ACS Code Generator DLL > Customizing a TDK code generation transformation patterns model - current TDK models > How TDK code generation transformation patterns models define code generation > Reuse of rules and operations - 4G business classes (TDK)
  
Reuse of rules and operations - 4G business classes (TDK)
4G Business Classes store Rules and Operations that can be reused by many 4G Generation Classes.
A 4G Business Classes is a Class that is stereotyped by the «4GBusiness» stereotype. In a TDK Code Generation Transformation Patterns model, the supplied Business Classes reside in the Generator::Model2Text package.
If a 4G Generation Classes wants to use a Role or Operation that is defined on a 4G Business Class, it must be linked to the 4G Business Classes through an abstraction Dependency. In turn, a 4G Business Classes can import Rules and Operations from another 4G Business Class through abstraction.
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Do not create new Roles and Operations on the provided 4G Business Class. If you do so and then update your TDK Code Generation Transformation Patterns model through a release of Modeler, your changes will be lost. Instead, define your own 4G Business Classes and extend the other Classes with them.