Storing and retrieving objects from an internal table

[Former Member]

Dear ABAPers,

I'm not sure how to do that in an elegant way. I need to store objects of any class (lets say that I will cast them to OBJECT) into an internal table. How could I define such a table? What would be the instructions to store and get back the objects then?

Sincerely,

Olivier MATT

[Former Member]

Dear ABAPers,

I'm not sure how to do that in an elegant way. I need to store objects of any class (lets say that I will cast them to OBJECT) into an internal table. How could I define such a table? What would be the instructions to store and get back the objects then?

Sincerely,

Olivier MATT

[uwe_schieferstein]

Hello Olivier

Here is an example using an <b>iterator class</b> (similar like in Java):

*&---------------------------------------------------------------------*
*& Report  ZUS_SDN_ITERATOR
*&
*&---------------------------------------------------------------------*
*&
*&
*&---------------------------------------------------------------------*

REPORT  zus_sdn_iterator.


DATA:
  gd_text        TYPE string,
  gs_viob03      TYPE viob03,
  gt_viob03      TYPE re_t_viob03,
*
  go_object      TYPE REF TO object,
  gto_list       TYPE swf_utl_object_tab,
  go_building    TYPE REF TO if_rebd_building,
  go_iterator    TYPE REF TO cl_swf_utl_iterator.


START-OF-SELECTION.

  SELECT * FROM  viob03 INTO TABLE gt_viob03
         WHERE  bukrs  = '1000'
         AND    swenr  = '00001000'.
  " selects three buildings on IDES ECC 5.0




  LOOP AT gt_viob03 INTO gs_viob03.
    CLEAR: go_building.

    CALL METHOD cf_rebd_building=>find
      EXPORTING
        id_bukrs       = gs_viob03-bukrs
        id_swenr       = gs_viob03-swenr
        id_sgenr       = gs_viob03-sgenr
         id_activity    = reca1_activity-display
         if_auth_check  = abap_false
*        IF_ENQUEUE     = ABAP_TRUE
*        IF_USE_ARCHIVE = ABAP_TRUE
      RECEIVING
        ro_instance    = go_building
       EXCEPTIONS
         error          = 1
         OTHERS         = 2.
    IF sy-subrc <> 0.
*     MESSAGE ID SY-MSGID TYPE SY-MSGTY NUMBER SY-MSGNO
*                WITH SY-MSGV1 SY-MSGV2 SY-MSGV3 SY-MSGV4.
    ENDIF.

    IF ( go_building IS BOUND ).
      APPEND go_building TO gto_list.
    ENDIF.

  ENDLOOP.


  " create iterator
  CREATE OBJECT go_iterator
    EXPORTING
      im_object_list = gto_list
*      IM_STARTPOINT = MC_START_TOP
      .


  CLEAR: go_building.
  go_building ?= go_iterator->get_first( ).  " casting OR
  "  go_object    = go_iterator->get_first( ).
  "  go_building ?= go_object.

  WHILE ( go_building IS BOUND ).
*   do something with the instance
    gd_text = go_building->get_text( ).
    WRITE: / go_building->ms_detail-bukrs,
             go_building->ms_detail-swenr,
             go_building->ms_detail-sgenr,
             gd_text.

    go_building ?= go_iterator->get_next( ).
  ENDWHILE.


END-OF-SELECTION.

Regards

Uwe

[RichHeilman]

This example shows how to build an internal table full of instances of classes.

report zrich_0001 .

*---------------------------------------------------------------------*
*       CLASS lcl_app DEFINITION
*---------------------------------------------------------------------*
*       ........                                                      *
*---------------------------------------------------------------------*
class lcl_app definition.


  public section.

    types: begin of ttab,
           fld1(10) type c,
           fld2(10)  type c,
           fld3(10)  type c,
           end of ttab.
    data: itab type table of ttab.
    data: xtab type ttab.

    methods: constructor, do_this.

endclass.

*---------------------------------------------------------------------*
*       CLASS lcl_app IMPLEMENTATION
*---------------------------------------------------------------------*
*       ........                                                      *
*---------------------------------------------------------------------*
class lcl_app implementation.

  method constructor.

    xtab-fld1 = 'ABC'.
    xtab-fld2 = 'DEF'.
    xtab-fld3 = 'GHI'.
    append xtab to itab.

  endmethod.

  method do_this.

    loop at itab into xtab.
      write:/ xtab-fld1, xtab-fld2, xtab-fld3.
    endloop.

  endmethod.

endclass.

data: a_app type ref to lcl_app.
data: a_app_list type table of ref to lcl_app.

start-of-selection.

  do 10 times.
    create object a_app.
    append a_app to a_app_list.
  enddo.

  loop at a_app_list into a_app.
    call method a_app->do_this( ).
  endloop.

Regards,

Rich Heilman

[Former Member]

Thanks for your help.

Unfortunately, I forgot to mention that I have a special case. I need to use an internal table (TYPE TABLE OF REF TO some_object_class) as an attribute of a class.

The Class Builder doesnt seem to allow me to enter such a type.

Is there any special trick to enforce this barrier? As I am pretty new to ABAP, I also wonder if there is a pure text-editing mode for classes (like in Java when you open the .java file of a class).

Any ideas?

Sincerely,

Olivier MATT

[RichHeilman]

You need to create a type type via SE11 which is TYPE REF to your class. Then use this table type in class builder when defining your attribute.

Also, about pure text-editing, you can when it comes to local classes, but not really with global classes(SE24) <i>yet</i>. There are options in the SE24 where you can go to the public sections, the private, and so on.

Regards,

Rich Heilman

[uwe_schieferstein]

Hello Oliver

The table type <b>SWF_UTL_OBJECT_TAB</b> does already fulfill your requirement in its <b>most generic</b> form (reference type is class OBJECT, the ROOT class of all ABAP classes). However, in order to develop more "Java-like" you could use the iterator class <b>CL_SWF_UTL_ITERATOR</b> as<i> instance attribute</i> of your class.

Regards

Uwe

[Former Member]

Please consider that there isn't in ABAP a concept of 'generics', like the last Java versions.

So the standard iterator class CL_SWF_UTL_ITERATOR operates on an internal table based on the generic OBJECT superclass. the programmer should take care to handle properly the actual types.

Regards,

Massimo