How To Fix /PM0/3FWM_TOOL402 - &1 is an interface and not a class

SAP Error Message - Details

• Message type: E = Error

• Message class: /PM0/3FWM_TOOL -

• Message number: 402

• Message text: &1 is an interface and not a class

Self-Explanatory Message

Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.

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Smart SAP Assistant

• What is the cause and solution for SAP error message /PM0/3FWM_TOOL402 - &1 is an interface and not a class ?

  The SAP error message /PM0/3FWM_TOOL402 &1 is an interface and not a class typically indicates that there is an attempt to use an interface in a context where a class is expected. This can occur in various scenarios, such as when trying to instantiate an interface or when using an interface in a place where a class type is required.
  Cause:
  
  Incorrect Usage: The error usually arises when a developer mistakenly tries to create an instance of an interface or uses an interface in a context that requires a concrete class.
  Code Logic Error: There may be a logical error in the code where the interface is being treated as a class.
  Configuration Issues: Sometimes, configuration settings or mappings in the system may incorrectly reference an interface instead of a class.
  
  Solution:
  
  
  Check Code: Review the code where the error occurs. Ensure that you are not trying to instantiate an interface. Instead, you should be using a class that implements the interface.
  
  Example: If you have an interface IF_MY_INTERFACE, you should instantiate a class that implements this interface, like CLASS_MY_IMPLEMENTATION.
  
  
  
  Review Method Calls: If the error occurs during a method call, ensure that the method is expecting an interface and that you are passing the correct implementation of that interface.
  
  
  Adjust Configuration: If the error is related to configuration, check the relevant settings in the SAP system to ensure that they are correctly pointing to the appropriate classes rather than interfaces.
  
  
  Debugging: Use debugging tools to trace the execution flow and identify where the interface is being incorrectly used.
  
  
  Documentation: Refer to the SAP documentation or the specific module documentation for guidance on the correct usage of interfaces and classes.
  
  
  Related Information:
  
  Interfaces vs. Classes: In ABAP (Advanced Business Application Programming), interfaces define a contract that classes can implement. They cannot be instantiated directly.
  ABAP Development Guidelines: Familiarize yourself with best practices in ABAP development, especially regarding the use of interfaces and classes.
  SAP Community: If you are unable to resolve the issue, consider reaching out to the SAP Community or forums for additional support and insights from other developers who may have encountered similar issues.
  
  By following these steps, you should be able to identify the root cause of the error and implement a suitable solution.