ABAP_to_the_Future

Using BOPF to Write a DYNPRO-Style Program 8.2
Figure 8.27 Action Validation Exception
Next, code the validation logic in your monster model class. This is shown in Listing
8.17, in which an exception is thrown if the monster has no head.
METHOD validate_howl_action.
IF is_header_values-no_of_heads EQ 0.
RAISE EXCEPTION TYPE zcx_monster_exceptions
EXPORTING
textid = zcx_monster_exceptions=>no_head_howling_problem.
ENDIF.
ENDMETHOD. "Validate Howl Action
Listing 8.17 Validating the Howl Action in the Monster Model Class
The final stage is to code the EXECUTE method in your action validation, which is
going to look suspiciously like the code in the consistency validation you created
earlier (see Listing 8.18).
METHOD /bobf/if_frw_validation~execute.
* Local Variables
DATA: lt_monster_header TYPE ztt_monster_header,
ls_monster_header LIKE LINE OF lt_monster_header,
lo_monster_model TYPE REF TO zcl_monster_model,
lo_monster_exception TYPE REF TO zcx_monster_exceptions.
* Clear Exporting Parameters
CLEAR: eo_message,
et_failed_key.
* Get the current header values
io_read->retrieve(
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