How To Fix CL791 - Class & cannot be assigned to other classes

SAP Error Message - Details

• Message type: E = Error

• Message class: CL - Classification

• Message number: 791

• Message text: Class & cannot be assigned to other classes

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message CL791 - Class & cannot be assigned to other classes ?

  The SAP error message CL791 indicates that a class cannot be assigned to other classes. This typically occurs in the context of object-oriented programming within the ABAP environment, particularly when dealing with class hierarchies and inheritance.
  Cause:
  The error can arise due to several reasons:
  
  Incorrect Class Definition: The class you are trying to assign may not be defined correctly or may not be compatible with the class you are trying to assign it to.
  Visibility Issues: The visibility of the class (public, protected, private) may prevent it from being assigned to another class.
  Abstract Classes: If the class is abstract, it cannot be instantiated or assigned in a way that would violate the rules of inheritance.
  Interface Implementation: If the class is supposed to implement an interface, but it does not correctly implement all the methods defined in that interface, it may lead to this error.
  Circular References: If there are circular references in the class hierarchy, it can lead to issues with class assignments.
  
  Solution:
  To resolve the CL791 error, consider the following steps:
  
  Check Class Definitions: Review the class definitions to ensure they are correctly defined and compatible with the intended hierarchy.
  Visibility Modifiers: Ensure that the visibility of the classes allows for the intended assignment. If necessary, change the visibility of the classes or methods.
  Abstract Classes: If you are dealing with abstract classes, ensure that you are not trying to instantiate them directly or assign them inappropriately.
  Interface Compliance: If the class is supposed to implement an interface, ensure that all required methods are implemented correctly.
  Review Inheritance Structure: Check for any circular references or incorrect inheritance structures that may be causing the issue.
  Recompile Classes: Sometimes recompiling the classes can help resolve issues related to class assignments.
  
  Related Information:
  
  ABAP Documentation: Refer to the official SAP documentation for more details on class definitions, inheritance, and object-oriented programming in ABAP.
  SAP Community: Engage with the SAP Community forums to see if others have encountered similar issues and how they resolved them.
  Debugging Tools: Use the ABAP debugger to step through the code and identify where the assignment is failing.
  
  By following these steps, you should be able to identify the root cause of the CL791 error and implement a suitable solution.