How To Fix REST_CORE_TEXTS028 - Creation of handler class failed (class not found)

SAP Error Message - Details

• Message type: E = Error

• Message class: REST_CORE_TEXTS -

• Message number: 028

• Message text: Creation of handler class failed (class not found)

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message REST_CORE_TEXTS028 - Creation of handler class failed (class not found) ?

  The SAP error message REST_CORE_TEXTS028: Creation of handler class failed (class not found) typically occurs in the context of developing or deploying RESTful services in SAP systems, particularly when using the SAP Gateway or SAP Cloud Platform.
  Cause:
  This error generally indicates that the system is unable to find the specified handler class that is supposed to process the incoming requests for the REST service. The reasons for this could include:
  
  Class Not Implemented: The handler class has not been implemented or is missing from the system.
  Incorrect Naming: The name of the handler class might be misspelled or incorrectly referenced in the service configuration.
  Transport Issues: If the class was recently transported from another system, it may not have been transported correctly or may not exist in the target system.
  Authorization Issues: The user executing the service may not have the necessary authorizations to access the handler class.
  Namespace Issues: The class might be in a different namespace than expected, leading to a failure in locating it.
  
  Solution:
  To resolve the error, you can follow these steps:
  
  
  Check Class Existence:
  
  Use transaction code SE80 or SE24 to check if the handler class exists in the system.
  Ensure that the class is correctly implemented and activated.
  
  
  
  Verify Naming:
  
  Double-check the service configuration to ensure that the handler class name is correctly specified.
  Ensure that there are no typos or case sensitivity issues.
  
  
  
  Transport Check:
  
  If the class was transported, verify that the transport request was successfully imported into the target system.
  Check for any transport errors that may have occurred during the import.
  
  
  
  Authorization Check:
  
  Ensure that the user executing the service has the necessary authorizations to access the handler class.
  You can check the authorization objects related to the service and the class.
  
  
  
  Namespace Verification:
  
  Confirm that the handler class is in the expected namespace. If it is in a different namespace, update the service configuration accordingly.
  
  
  
  Rebuild the Service:
  
  If the above steps do not resolve the issue, consider rebuilding the service using transaction code /IWFND/MAINT_SERVICE to regenerate the service and its associated artifacts.
  
  
  
  Check Logs:
  
  Review the application logs (transaction SLG1) for any additional error messages or details that might provide more context about the failure.
  
  
  
  Related Information:
  
  SAP Documentation: Refer to the official SAP documentation for RESTful services and the SAP Gateway for more detailed information on service creation and troubleshooting.
  SAP Community: Engage with the SAP Community forums to see if others have encountered similar issues and to find additional solutions or workarounds.
  SAP Notes: Check for any relevant SAP Notes that might address known issues related to this error message.
  
  By following these steps, you should be able to identify and resolve the cause of the error message REST_CORE_TEXTS028 in your SAP environment.