How To Fix GENIL_WCF171 - Object &3: Substituted handler class &1 has to be derived from &2

SAP Error Message - Details

• Message type: E = Error

• Message class: GENIL_WCF - Messages for genIL Model Editor

• Message number: 171

• Message text: Object &3: Substituted handler class &1 has to be derived from &2

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message GENIL_WCF171 - Object &3: Substituted handler class &1 has to be derived from &2 ?

  The SAP error message GENIL_WCF171 indicates that there is an issue with the handler class in the context of the Generic Interaction Layer (GENIL) and the Web Client Framework (WCF). Specifically, the error message states that the substituted handler class (&1) must be derived from a specific base class (&2), and it is associated with a particular object (&3).
  Cause:
  This error typically occurs due to one of the following reasons:
  
  Incorrect Class Implementation: The substituted handler class does not inherit from the required base class. This can happen if the developer has created a new handler class but has not properly extended the correct base class.
  Configuration Issues: There may be a misconfiguration in the GENIL model or the WCF configuration that points to the wrong handler class.
  Transport Issues: If the handler class was recently transported from another system, it may not have been properly imported or activated in the target system.
  
  Solution:
  To resolve the GENIL_WCF171 error, you can follow these steps:
  
  
  Check Class Inheritance:
  
  Verify that the substituted handler class (&1) is correctly derived from the required base class (&2). You can do this by checking the class definition in the ABAP Workbench (transaction SE80 or SE24).
  If the class does not inherit from the correct base class, modify the class definition to ensure it extends the appropriate class.
  
  
  
  Review Configuration:
  
  Check the GENIL model configuration to ensure that the correct handler class is assigned to the object (&3). This can be done in the transaction code GENIL_MODEL or through the relevant configuration transactions.
  Ensure that the configuration is consistent and that there are no typos or incorrect references.
  
  
  
  Transport and Activation:
  
  If the handler class was recently transported, ensure that it has been activated in the target system. You can do this by navigating to the class in SE80 or SE24 and checking its activation status.
  If necessary, re-transport the class or manually activate it.
  
  
  
  Check for Dependencies:
  
  Ensure that all dependencies of the handler class are also correctly implemented and activated. This includes any interfaces or abstract classes that the handler may depend on.
  
  
  
  Debugging:
  
  If the issue persists, consider debugging the application to trace where the error is being triggered. This can provide additional context on what might be going wrong.
  
  
  
  Related Information:
  
  GENIL: The Generic Interaction Layer is a framework in SAP that allows for the creation of business object models and their interaction with various UI technologies.
  WCF: The Web Client Framework is used to build web-based applications in SAP, leveraging the GENIL model for data access and manipulation.
  ABAP Workbench: Use transaction SE80 or SE24 to navigate and manage classes, interfaces, and other development objects in SAP.
  
  By following these steps, you should be able to identify and resolve the issue causing the GENIL_WCF171 error message. If the problem continues, consider reaching out to SAP support or consulting the SAP community for further assistance.