Now that annotations are making UI5 development easier by using Smart controls, it is important to learn how to add these annotations to your service. SEGW does not yet allow you to add most of the annotations. Till SEGW inherently provides that feature, here is how you can do it using code.
Step 1. Goto you MPC_EXT class
Step 2. Redefine Define method.
Step 3. Write this code.
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.
This will result in
