Call Function in CL_RSPLS_CR_EXIT_BASE to derive values

Question

Dear all,
we want to derive the location from item (material). If item gebinns with "EMU" then location is 2. If item beginns with "X" then locations is "68" and so on.
To realise we chose characteristic relationship with derivation and based on "Exit Class".
we copied the Class "CL_RSPLS_CR_EXIT_BASE" to "Z_CL_RSPLS_CR_EXIT_BASE". Now we want to call a function method "IF_RSPLS_CR_METHODS~DERIVE" like:
implement your derivation algorithm here:
  field-symbols: <l_chavl> type any.
  assign component 'BW_LAGER' of structure c_s_chas to <l_chavl>.
CALL FUNCTION 'Z_ST_BW_LAGER'
The function look like:
FUNCTION Z_ST_BW_LAGER.
""Lokale Schnittstelle:
*"  EXPORTING
*"     REFERENCE(BW_LAGER) TYPE  /BIC/OIBW_LAGER
lesen
But we did not know wich are the IMPORTING (like I_INFOPROV ?) parameters to fecht the values for the data. In BW-BPS we have UPC_Y_AREA, UPC_Y_VARIABLE, UPY_Y_CHANM and so on. Wich are the same in BI-integrated planning.
Regards,
Daniel Meyer

Answer 1

Dear all,
we use this code:
  field-symbols: <l_chavl> type any.
  DATA: LAGER(2).
  assign component '/BIC/P_RMRESC' of structure c_s_chas to <l_chavl>.
  IF <l_chavl>+0(3) = 'EMU'.
    LAGER = '2'.
  ELSEIF <l_chavl>+0(1) = 'O'.
    LAGER = '1'.
  ENDIF.
  <l_s_buf>+2(15) = <l_chavl>.
  assign component '/BIC/BW_LAGER' of structure c_s_chas to <l_chavl>.
  <l_chavl> = LAGER.
  <l_s_buf>+0(2) = <l_chavl>.
But now we have the problem, how to write ist back to the buffer? If we debugg it, we see in this code:
  IF o_use_buffer = rs_c_true.
    o_r_is_valid->* = l_is_valid.
    IF o_r_is_valid->* = rs_c_true.
      INSERT <l_s_buf> INTO TABLE <l_th_buf>.
      c_s_chas = <l_s_buf>.
    ELSE.
      IF e_t_mesg IS SUPPLIED.
        o_r_s_mesg->* = l_s_mesg.
        APPEND l_s_mesg TO e_t_mesg.
      ENDIF.
      INSERT <l_s_buf> INTO TABLE <l_th_buf>.
      RAISE EXCEPTION TYPE cx_rspls_failed
        EXPORTING
          msgid = l_s_mesg-msgid
          msgty = l_s_mesg-msgty
          msgno = l_s_mesg-msgno
          msgv1 = l_s_mesg-msgv1
          msgv2 = l_s_mesg-msgv2
          msgv3 = l_s_mesg-msgv3
          msgv4 = l_s_mesg-msgv4.
    ENDIF.
  ENDIF.
that o_r_is_valid->* has no value, so he goes to the ELSE-part.
Could anyone help?
Regards,
Daniel