How To Fix OO305 - Parameter &1 &2 &3: Only IMPORTING / CHANGING parameters can be optional

OO305 - Overview

• Message type: E = Error

• Message class: OO - Class Builder/API

• Message number: 305

• Message text: Parameter &1 &2 &3: Only IMPORTING / CHANGING parameters can be optional

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message OO305 - Parameter &1 &2 &3: Only IMPORTING / CHANGING parameters can be optional ?

  The SAP error message OO305 indicates that there is an issue with the parameters defined in a method of a class or an interface. Specifically, it states that only IMPORTING or CHANGING parameters can be optional, and it typically occurs when you try to define a parameter as optional that is not of the correct type (i.e., it is not an IMPORTING or CHANGING parameter).
  
  Cause:
  The error arises when:
  
  You have defined a parameter in a method as optional, but it is not an IMPORTING or CHANGING parameter.
  The method signature is incorrectly defined, possibly due to a misunderstanding of how optional parameters work in ABAP Object-Oriented programming.
  
  
  Solution:
  To resolve this error, you should:
  
  
  Check the Method Definition: Review the method signature in the class or interface where the error occurs. Ensure that only IMPORTING or CHANGING parameters are marked as optional.
  
  
  Modify Parameter Types: If you have a parameter that is defined as EXPORTING or