FUNCTION Z_MES_BEGIN.
*"----------------------------------------------------------------------
*"*"Локальный интерфейс:
*"  IMPORTING
*"     VALUE(I_AREA) TYPE  UPC_Y_AREA
*"     VALUE(I_VARIABLE) TYPE  UPC_Y_VARIABLE
*"     VALUE(I_CHANM) TYPE  UPC_Y_CHANM
*"     VALUE(ITO_CHANM) TYPE  UPC_YTO_CHA
*"  EXPORTING
*"     REFERENCE(ETO_CHARSEL) TYPE  UPC_YTO_CHARSEL
*"----------------------------------------------------------------------
CONSTANTS:
  l_source_var TYPE upc_y_variable VALUE 'ZMESPER',
* l_source_area TYPE upc_y_area VALUE 'ZTEST',
  l_use_restricted_values TYPE boole-boole VALUE 'X',
  l_buffer_call TYPE boole-boole VALUE ' '.

DATA:
l_subrc LIKE sy-subrc,
ls_return LIKE bapiret2,
l_type LIKE upc_var-vartype,
lto_varsel_all TYPE upc_yto_charsel,
lto_varsel TYPE upc_yto_charsel,
lto_var TYPE upc_yto_charsel,
lto_chanm TYPE upc_yto_cha.

* read source value
CALL FUNCTION 'Z_VARIABLE_GET_DETAIL'
EXPORTING
i_area = i_area
i_variable = l_source_var
i_buffer = l_buffer_call
IMPORTING
e_subrc = l_subrc
es_return = ls_return
e_type = l_type
eto_varsel_all = lto_varsel_all
eto_varsel = lto_varsel
eto_chanm = lto_chanm.

IF l_subrc <> 0.
*MESSAGE i136(upc_fw) WITH l_source_var.
* Values of variable &1 cannot be determined
EXIT.
ENDIF.


* now, you are free to determine the logic on how to
* derive the values based on the source values.
DATA: ls_varsel TYPE upc_ys_charsel,
l_month(6) TYPE n,
l_entries TYPE i.

* We have a single value for the year and only one characteristic
* => our value is stored in the first line
IF l_use_restricted_values IS INITIAL.
lto_var = lto_varsel_all.
ELSE.
lto_var = lto_varsel.
ENDIF.

READ TABLE lto_var INTO ls_varsel INDEX 1.
* check prerequisites:
* - record found?
IF sy-subrc <> 0.
*MESSAGE i147(upc_fw) WITH l_source_var.
* Variable &1 does not contain any values
EXIT.
ENDIF.

* - exactly one record and characteristic?
DESCRIBE TABLE lto_var LINES l_entries.
IF l_entries <> 1.
*MESSAGE i534(upc) WITH l_source_var.
* Variable &1 must be restricted to a value
EXIT.
ENDIF.

l_month = ls_varsel-low.

l_month+4(2) = '01'.

ls_varsel-low = l_month.
APPEND ls_varsel TO eto_charsel.

ENDFUNCTION.

FUNCTION Z_VARIABLE_GET_DETAIL.
*"----------------------------------------------------------------------
*"*"Локальный интерфейс:
*"  IMPORTING
*"     REFERENCE(I_AREA) TYPE  UPC_VAR-AREA
*"     REFERENCE(I_VARIABLE) TYPE  UPC_VAR-VAR
*"     REFERENCE(I_BUFFER) TYPE  BOOLE-BOOLE OPTIONAL
*"  EXPORTING
*"     VALUE(E_SUBRC) TYPE  SY-SUBRC
*"     VALUE(ES_RETURN) TYPE  BAPIRET2
*"     VALUE(E_TYPE) TYPE  UPC_VAR-VARTYPE
*"     REFERENCE(ETO_VARSEL_ALL) TYPE  UPC_YTO_CHARSEL
*"     REFERENCE(ETO_VARSEL) TYPE  UPC_YTO_CHARSEL
*"     REFERENCE(ETO_CHANM) TYPE  UPC_YTO_CHA
*"----------------------------------------------------------------------

STATICS:
p_subrc LIKE sy-subrc,
ps_return LIKE bapiret2,
p_type LIKE upc_var-vartype,
pto_varsel_all TYPE upc_yto_charsel,
pto_varsel TYPE upc_yto_charsel,
pto_chanm TYPE upc_yto_cha,
p_variable TYPE upc_var-var,
p_area TYPE upc_y_area,
p_first_read LIKE boole-boole VALUE 'X'.

DATA:
lr_variable TYPE REF TO cl_sem_variable.

* We can't read the values from the buffer if ...
* - it is the first read
* - the buffer flag is initial
* - the stored area or varname differ from imported values.

IF NOT i_buffer IS INITIAL
   AND p_first_read IS INITIAL
   AND p_area = i_area
   AND p_variable = i_variable.

e_subrc = p_subrc.
es_return = ps_return.
eto_varsel_all = pto_varsel_all.
eto_varsel = pto_varsel.
eto_chanm = pto_chanm.
ELSE.

* clear all exporing tables of type reference

clear: eto_chanm, eto_varsel_all, eto_varsel.
CALL METHOD cl_sem_variable=>get_instance
  EXPORTING
   i_area = i_area
   i_variable = i_variable
  RECEIVING
   rr_variable = lr_variable
  EXCEPTIONS
   not_existing = 1
   OTHERS = 2.

IF sy-subrc <> 0.
e_subrc = 4.
CALL FUNCTION 'BALW_BAPIRETURN_GET2'
  EXPORTING
   type = sy-msgty
   cl = sy-msgid
   number = sy-msgno
   par1 = sy-msgv1
   par2 = sy-msgv2
   par3 = sy-msgv3
   par4 = sy-msgv4
  IMPORTING
   return = es_return.
EXIT.
ENDIF.
*read details of variable
CALL METHOD lr_variable->get_attributes
  IMPORTING
     e_type = e_type
     eto_chanm = eto_chanm.

*read restricted values
CALL METHOD lr_variable->get_value
  EXPORTING
     i_user = sy-uname
     i_restrict = 'X'
  RECEIVING
     rto_value = eto_varsel
  EXCEPTIONS
     error = 1
     OTHERS = 2.

IF sy-subrc <> 0.
    e_subrc = 4.
    CALL FUNCTION 'BALW_BAPIRETURN_GET2'
     EXPORTING
      type = sy-msgty
      cl = sy-msgid
      number = sy-msgno
      par1 = sy-msgv1
      par2 = sy-msgv2
      par3 = sy-msgv3
      par4 = sy-msgv4
     IMPORTING
      return = es_return.
  EXIT.
ENDIF.

* read all values
CALL METHOD lr_variable->get_value
   EXPORTING
    i_user = sy-uname
    i_restrict = ' '
   RECEIVING
    rto_value = eto_varsel_all
   EXCEPTIONS
    error = 1
    OTHERS = 2.

IF sy-subrc <> 0.
    e_subrc = 4.
   CALL FUNCTION 'BALW_BAPIRETURN_GET2'
    EXPORTING
     type = sy-msgty
     cl = sy-msgid
     number = sy-msgno
     par1 = sy-msgv1
     par2 = sy-msgv2
     par3 = sy-msgv3
     par4 = sy-msgv4
    IMPORTING
     return = es_return.
  EXIT.
ENDIF.

* -- no error occured => store results
CLEAR p_first_read.
p_area = i_area.
p_variable = i_variable.
p_subrc = e_subrc.
ps_return = es_return.
pto_varsel_all = eto_varsel_all.
pto_varsel = eto_varsel.
pto_chanm = eto_chanm.

ENDIF.
ENDFUNCTION.