Output length problem

Question

Hi,
I have created a dynamic structure and a dynamic internal table and I have populated the dynamic internal table with values.
For the above operations, I have used RTTS(Runtime Type Services).
Please see my code below,
DATA : BEGIN OF xx,
  char(100) TYPE c,
  END OF xx.
DATA : wa_xx LIKE xx.
DATA : int LIKE STANDARD TABLE OF xx.
" The internal table 'int" contains all of the "data elements", upon which structure and table needs to be created
DATA:l_elem_descr  TYPE REF TO cl_abap_elemdescr,
l_struct_descr TYPE REF TO cl_abap_structdescr,
l_table_descr TYPE REF TO cl_abap_tabledescr,
l_comp TYPE cl_abap_structdescr=>component,
lt_comp TYPE cl_abap_structdescr=>component_table.
FIELD-SYMBOLS : <wa> TYPE ANY, <itab> TYPE STANDARD TABLE, <comp_trg> TYPE ANY,<comp_trg> type any.
" looping through each value of internal table and creating a element of that type
LOOP AT int INTO wa_xx.
  l_elem_descr ?= cl_abap_elemdescr=>describe_by_name( wa_xx-char ). u201Cwa-char contains data elements
  l_comp-type = l_elem_descr.
  l_comp-name = wa_xx-char.
  WRITE : / l_elem_descr->output_length.
  APPEND l_comp TO lt_comp.
ENDLOOP.
" Creating a structure from the list of elements available in the table lt_comp
u201C We have element name and its data type with size
u201C But we do not have its output length
IF  lt_comp IS NOT INITIAL.
  TRY.
      l_struct_descr  = cl_abap_structdescr=>create( lt_comp ).
      CREATE DATA dref TYPE HANDLE l_struct_descr.
      ASSIGN dref->* TO <wa>.
    CATCH cx_sy_struct_creation INTO gcx_sy_struct_creation.
      gv_msg_txt = gcx_sy_struct_creation->get_text( ).
      MESSAGE gv_msg_txt TYPE 'E'.
  ENDTRY.
ENDIF.
" ETK_ROW is a table which contains values for the dynamically created table
u201CThese values must be supplied to <wa> and later <wa> must be inserted to <itab>
LOOP AT etk_row INTO etk_wa.
    ASSIGN COMPONENT count OF STRUCTURE <wa> TO <comp_trg>.
    <comp_trg> = etk_wa-chavlext.
   UNASSIGN <comp_trg>.
  ENDLOOP.
The problem I face is the "data elements" size is obtained in <wa> but not its output length.
For example, I have supplied a data element u201CABCu201D to the internal table "int".
The data element ABC contains domain DATUM, its size is 8 and output  length is 10.
The data contained in the etk_wa-chavlext is 03/03/2011.
Which is assigned to <wa>.
But what is see in my <wa> is 03/03/20 (because size is only 8, not 10).
That is,  "l_comp" is of type  cl_abap_structdescr=>component.
when I checked its structure ( cl_abap_structdescr=>component), it contains,
Component Technical type
NAME      CString* Name of the component 
TYPE               Reference   * its type (data element)
AS_INCLUDE C(1)            *  Boolean type
SUFFIX          CString  * String
The above structure does not contain output length. It contains only name and data type.
I am filling only the name and type as per the structure via the lines
  l_comp-type = l_elem_descr.
  l_comp-name = wa_xx-char. u201Cdata element
Now this structure is appended to the  lt_comp and which is of type cl_abap_structdescr=>component_table.
Now a structure is created based on the componenet table lt_comp,
l_struct_descr  = cl_abap_structdescr=>create( lt_comp ).
CREATE DATA dref TYPE HANDLE l_struct_descr.
ASSIGN dref->* TO <wa>.
The field-symbol <wa> is of type any and its structure is same as that of cl_abap_structdescr=>component.
I have seen that the there is a element u201Coutput_lengthu201D in the class  cl_abap_elemdescr.
When I checked it it contains the correct output length and this output length must be supplied to <wa> so that it accepts 03/03/2011.
Is there any way of doing it? I need my <wa>  to accept the incoming data, as per the output length mentioned in the domain of that data element.
Please help.

Answer 1

Hi,
Actually i have taken the approach of  give up using D type and use C type, now the code works very much fine.
Thanks a lot for your suggestions,
Below is my code, where i have implemented C instead of D.
LOOP AT int INTO wa_xx.
  TRY.
      descr_ref = cl_abap_elemdescr=>describe_by_name( wa_xx-char ). " Element description
      WRITE: / 'Typename:', descr_ref->absolute_name.
      WRITE: / 'Length  :', descr_ref->length.
      WRITE: / 'Decimals:', descr_ref->decimals.
      abap_typekind_l = descr_ref->type_kind.
    CATCH cx_dynamic_check INTO exc_obj.
      abap_typekind_l = 'C'.
  ENDTRY.
  l_elem_descr ?= cl_abap_elemdescr=>describe_by_name( wa_xx-char ).
  output_len = l_elem_descr->output_length.  " output length
  IF  abap_typekind_l  IS NOT INITIAL.
    IF abap_typekind_l EQ 'C'.
      l_elemtype =  cl_abap_elemdescr=>get_c( p_length = output_len ).
    ENDIF.
    IF abap_typekind_l EQ 'N'.
      l_elemtype =  cl_abap_elemdescr=>get_n( p_length = output_len ).
    ENDIF.
    IF abap_typekind_l EQ 'D'.
      l_elemtype =  cl_abap_elemdescr=>get_c( p_length = output_len ).
    ENDIF.
    IF abap_typekind_l EQ 'T'.
      l_elemtype =  cl_abap_elemdescr=>get_c( p_length = output_len ).
    ENDIF.
  ENDIF.
  l_comp-name = wa_xx-char.
  l_comp-type ?= l_elemtype.
  APPEND l_comp TO lt_comp.
ENDLOOP.
Now i face a peculiar problem. See in SAP BI a characteristic info object can be with data type (c,n,d,t,UNIT, CUKY).
Now my code works well for the data types c,n,d,t, but if the data type is either UNIT or CUKY then my code throws exception "type_not_found.". This is because the method "describe_by_name" does not create the data type. Also i cannot use try...end try, as the exception is not propagated to the code. otherwise i could catch the same and convert the type to 'C'.
Further investigation i have found the method "CREATE_ELEMDESCR_OBJECT" but i am not aware of how to use the same to attain my goal. Any help is much appreciated. Thanks.