Define for Annotations

    DATA:
     lo_annotation     TYPE REF TO /iwbep/if_mgw_odata_annotation, "#EC NEEDED
     lo_entity_type    TYPE REF TO /iwbep/if_mgw_odata_entity_typ, "#EC NEEDED
     lo_property       TYPE REF TO /iwbep/if_mgw_odata_property. "#EC NEEDED
    
    super->define( ). "Ensure you call the parent metadata
    lo_entity_type = model->get_entity_type( iv_entity_name = 'EmpDetail'). "Your Entity Name
    lo_property = lo_entity_type->get_property( iv_property_name = 'DateOfHire'). "Property inside your Entity
    lo_annotation = lo_property-/iwbep/if_mgw_odata_annotatabl~create_annotation( /iwbep/if_mgw_med_odata_types=>gc_sap_namespace ). "SAP's annotations
    lo_annotation->add( iv_key = 'display-format' iv_value = 'Date' ). "Specific annotation you want to add.