How To Fix FDT_CORE147 - No valid class, &1 does not exist or does not implement interface &2

SAP Error Message - Details

• Message type: E = Error

• Message class: FDT_CORE - Formula & Derivation Tool: Core

• Message number: 147

• Message text: No valid class, &1 does not exist or does not implement interface &2

What causes this issue?

The signature of an BRFplus expression type is defined by an ABAP-OO
interface. The functionality is defined in an ABAP-OO class implementing
that interface. This class also needs to implement the interface
IF_FDT_EXPRESSION.
Optionally there can be further classes defined for an expression type.
These are a query class, a UI class and a data exchange class. For a
detailed description of the functionality provided by these classes,
refer to the BRFplus documentation. If one of the classes is set it
needs to implement a corresponding interface.
These are the following:
The query class needs to implement IF_FDT_OBJECT_QUERY
The UI class needs to implement IF_FDT_UI_DEFINITION
The data exchange class needs to implement IF_FDT_DATA_EXCHANGE_EXTERNAL

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

Specify a correct interface and correct classes for the expression type.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message FDT_CORE147 - No valid class, &1 does not exist or does not implement interface &2 ?

  The SAP error message FDT_CORE147 indicates that there is an issue with a class not being valid or not implementing a required interface. This error typically arises in the context of SAP's Flexible Data Import (FDI) or Flexible Data Transfer (FDT) framework, which is used for data handling and processing.
  Cause:
  
  Class Not Found: The specified class (&1) does not exist in the system. This could be due to a typo in the class name or the class not being activated.
  Interface Not Implemented: The class exists but does not implement the required interface (&2). This means that the class is not fulfilling the contract defined by the interface, which is necessary for the operation to proceed.
  Transport Issues: If the class was recently transported from another system, it may not have been transported correctly, or dependencies may be missing.
  Authorization Issues: The user may not have the necessary authorizations to access the class or interface.
  
  Solution:
  
  Check Class Existence: Verify that the class specified in the error message exists in the system. You can do this by using transaction SE24 (Class Builder) to search for the class name.
  Check Interface Implementation: If the class exists, check whether it implements the required interface. You can do this by viewing the class in SE24 and checking the "Interfaces" tab.
  Activate Class: If the class is not activated, activate it in SE24.
  Review Transport Requests: If the class was recently transported, ensure that all related transport requests were successfully imported and that there are no missing dependencies.
  Check Authorizations: Ensure that the user has the necessary authorizations to access the class and interface.
  Debugging: If the issue persists, consider debugging the code that is trying to instantiate the class to get more context on why the error is occurring.
  
  Related Information:
  
  Transaction Codes: 
  
  SE24: Class Builder
  SE80: Object Navigator
  SE11: Data Dictionary (to check related database objects)
  
  
  Documentation: Refer to SAP Help documentation for FDT and FDI for more details on how classes and interfaces are used within the framework.
  SAP Notes: Check for any relevant SAP Notes that might address known issues related to this error message.
  
  If the problem continues after following these steps, it may be beneficial to consult with your SAP Basis or development team for further investigation.