Level assignment dynamicaly, OO Example

[tolga_polat]

I wrote this code for answer of this question :

http://scn.sap.com/thread/3390691

I inspired from steve.rumsby blog : http://scn.sap.com/community/abap/blog/2013/04/23/object-oriented-sieve-of-eratosthenes

Here is my code... If you see any misuse of OO or better way to do this, plase let me know.

DATA : BEGIN OF ls_bom,

         stufe TYPE i,

         level TYPE char20,

        END OF ls_bom,

        it_bom LIKE STANDARD TABLE OF ls_bom.

 *----------------------------------------------------------------------*

 *       CLASS lcl_determine_level DEFINITION

 *----------------------------------------------------------------------*

 *

 *----------------------------------------------------------------------*

 CLASS lcl_determine_level DEFINITION FINAL.

   PUBLIC SECTION.

     METHODS : constructor

                IMPORTING

                  i_stufe TYPE i.

     METHODS : get_level

                IMPORTING

                  i_stufe TYPE i

                RETURNING value(r_level) TYPE char20,

                get_level_chr

                 RETURNING value(r_level) TYPE char20.

   PROTECTED SECTION.

     DATA : level TYPE REF TO lcl_determine_level.

   PRIVATE SECTION.

     DATA : value TYPE i,

            lvl TYPE i,

            level_chr TYPE char20.

 ENDCLASS.                    "lcl_determine_level DEFINITION

 *----------------------------------------------------------------------*

 *       CLASS lcl_determine_level IMPLEMENTATION

 *----------------------------------------------------------------------*

 *

 *----------------------------------------------------------------------*

 CLASS lcl_determine_level IMPLEMENTATION.

   METHOD constructor.

     super->constructor( ).

     value = i_stufe.

   ENDMETHOD.                    "constructor

   METHOD get_level.

     IF value = i_stufe.

       ADD 1 TO lvl.

       WRITE : lvl TO level_chr.

       CONDENSE level_chr.

       r_level = level_chr.

     ENDIF.

   ENDMETHOD.                    "get_level

   METHOD get_level_chr.

     r_level = level_chr.

   ENDMETHOD.                    "get_level_chr

 ENDCLASS.                    "lcl_determine_level IMPLEMENTATION

 *----------------------------------------------------------------------*

 *       CLASS lcl_bom DEFINITION

 *----------------------------------------------------------------------*

 *

 *----------------------------------------------------------------------*

 CLASS lcl_bom DEFINITION.

   PUBLIC SECTION.

     METHODS: constructor

               IMPORTING

                 i_stufe TYPE i,

               get_level

                 IMPORTING

                   i_stufe TYPE i

                 RETURNING value(r_level) TYPE char20.

   PRIVATE SECTION.

     DATA: level TYPE REF TO lcl_determine_level,

           bom TYPE REF TO lcl_bom.

 ENDCLASS.                    "lcl_bom DEFINITION

 *----------------------------------------------------------------------*

 *       CLASS lcl_bom IMPLEMENTATION

 *----------------------------------------------------------------------*

 *

 *----------------------------------------------------------------------*

 CLASS lcl_bom IMPLEMENTATION.

   METHOD constructor.

     DATA : lo_level TYPE REF TO lcl_determine_level.

     CREATE OBJECT lo_level

       EXPORTING

         i_stufe = i_stufe.

     level = lo_level.

   ENDMETHOD.                    "constructor

   METHOD get_level.

     DATA : level_chr TYPE char20.

     r_level = level->get_level( i_stufe ).

     IF r_level EQ 0.

       level_chr = level->get_level_chr( ).

       IF bom IS NOT BOUND.

         CREATE OBJECT bom

           EXPORTING

             i_stufe = i_stufe.

       ENDIF.

       r_level = bom->get_level( i_stufe ).

       CONCATENATE level_chr

                   '.'

                   r_level

              INTO r_level.

       CONDENSE r_level.

     ELSE.

       FREE bom.

     ENDIF.

   ENDMETHOD.                    "geT_level

 ENDCLASS.                    "lcl_bom IMPLEMENTATION

 FIELD-SYMBOLS : <wa> LIKE LINE OF it_bom.

 DATA : lo_bom TYPE REF TO lcl_bom.

 START-OF-SELECTION.

   ls_bom-stufe = 1.

   APPEND ls_bom

       TO it_bom.

   ls_bom-stufe = 2.

   APPEND ls_bom

       TO it_bom.

   ls_bom-stufe = 2.

   APPEND ls_bom

       TO it_bom.

   ls_bom-stufe = 3.

   APPEND ls_bom

     TO it_bom.

   ls_bom-stufe = 3.

   APPEND ls_bom

       TO it_bom.

   ls_bom-stufe = 4.

   APPEND ls_bom

       TO it_bom.

   ls_bom-stufe = 4.

   APPEND ls_bom

       TO it_bom.

   ls_bom-stufe = 2.

   APPEND ls_bom

       TO it_bom.

   ls_bom-stufe = 2.

   APPEND ls_bom

       TO it_bom.

   ls_bom-stufe = 3.

   APPEND ls_bom

       TO it_bom.

   ls_bom-stufe = 4.

   APPEND ls_bom

       TO it_bom.

   ls_bom-stufe = 4.

   APPEND ls_bom

       TO it_bom.

   ls_bom-stufe = 4.

   APPEND ls_bom

       TO it_bom.

   ls_bom-stufe = 5.

   APPEND ls_bom

       TO it_bom.

   ls_bom-stufe = 5.

   APPEND ls_bom

       TO it_bom.

   BREAK-POINT.

   DATA : lv_level TYPE i.

   LOOP AT it_bom

      ASSIGNING <wa>.

     IF lo_bom IS NOT BOUND.

       CREATE OBJECT lo_bom

         EXPORTING

           i_stufe = <wa>-stufe.

     ENDIF.

     <wa>-level = lo_bom->get_level( <wa>-stufe ).

   ENDLOOP.

   BREAK-POINT.

this is the result :

Regards

Tolga POLAT