Level assignment dynamicaly, OO Example

I wrote this code for answer of this question :

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

I inspired from Steve Rumsby blog : https://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 :  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 .      IF lo_bom IS NOT BOUND.        CREATE OBJECT lo_bom          EXPORTING            i_stufe = -stufe.      ENDIF.      -level = lo_bom->get_level( -stufe ).    ENDLOOP.    BREAK-POINT.

this is the result :

Regards

Tolga POLAT