Convert Object to long

[Ippez Robert]

Hi dev,
May i know how i can return long value from an object AppUser userId.
Check below method:

public String createLogDetail(@PathParam("userId") final AppUser userId, final 
String apiRequestBodyAsJson) {
        
        final Long userToSubscribe = (long) userId.getId(); 
    }

This throws error an error that 'createLogDetail' is not recognized as valid 
resource method.
Exception occurred when intialization SEVERE: Missing dependency for method 
public java.lang.String
(org.apache.fineract.useradministration.domain.AppUser,java.lang.String) at 
parameter at index 0

Any assistance is appreciated.
Thanks
Regards
Ippez Robert