table type with reference type -> how to sort?

[daniel_humberg]

I have an internal table lt_refs of the type ZXX_TT_REFS.

The table type ZXX_TT_REFS is a table of references ("ref. type") to the class ZCL_C.

The class C has an attribute attr1.

Now I would like to sort that table. Is there an easy (built-in) way to do this?

DATA lt_refs TYPE ZXX_TT_REFS.
DATA lr_ref  TYPE REF TO ZCL_C.
LOOP AT lt_refs INTO lr_ref.
  "Sort based on lr_ref->attr1. ?
ENDLOOP.
"or can I 
SORT lt_refs BY attr1.
"directly?

[RichHeilman]

You can sort by referencing the attribute of the object. See below.

report zrich_0001.

*---------------------------------------------------------------------*
*       CLASS lcl_tab DEFINITION
*---------------------------------------------------------------------*
*       ........                                                      *
*---------------------------------------------------------------------*
class lcl_tab definition.

  public section.

    types: ttab type table of string.

    data: itab type ttab.
    methods: constructor importing im_tab type ttab.

endclass.


*---------------------------------------------------------------------*
*       CLASS lcl_tab IMPLEMENTATION
*---------------------------------------------------------------------*
*       ........                                                      *
*---------------------------------------------------------------------*
class lcl_tab implementation.
  method constructor.
    itab[] = im_tab[].
  endmethod.

endclass.

data: l_itab type table of string.
data:  l_wa type string.
data: a_tab type ref to lcl_tab.

start-of-selection.

  l_wa = 'B'.  append l_wa to l_itab.
  l_wa = 'C'.  append l_wa to l_itab.
  l_wa = 'D'.  append l_wa to l_itab.
  l_wa = 'A'.  append l_wa to l_itab.

  create object a_tab
        exporting
            im_tab = l_itab.


<b>  sort a_tab->itab ascending.</b>


  check sy-subrc = 0.

REgards,

RIch Heilman

[daniel_humberg]

Hi Rich,

sure, I can sort an internal table that is the attribute of a class.

By how can I sort an interal table that itself consists of a list of references to objects of a class?

[RichHeilman]

How exactly would you like to sort it? By object reference identifier?

REgards,

Rich Heilman

[Former Member]

And for what purpose? They are simply dynamically created references.

[RichHeilman]

Danial, please see the following. In the case where you want to sort your reference by an attribute within the object, you can do something like this.

report zrich_0001.











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

  public section.
    data: attri type i.
    methods: constructor importing im_attri type i.

endclass.


*---------------------------------------------------------------------*
*       CLASS lcl_tab IMPLEMENTATION
*---------------------------------------------------------------------*
*       ........                                                      *
*---------------------------------------------------------------------*
class lcl_app implementation.
  method constructor.
    attri = im_attri.
  endmethod.

endclass.


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

start-of-selection.



  create object a_app exporting im_attri =  3 .
  append a_app to a_app_list.
  create object a_app exporting im_attri =  2 .
  append a_app to a_app_list.
  create object a_app exporting im_attri =  1 .
  append a_app to a_app_list.



  sort a_app_list by <b>table_line->attri</b> ascending .

  check sy-subrc = 0.

Here is the documentation.

<i>

<b>

Access to Attributes with References in Internal Tables</b>

If the line type of internal tables includes reference variables as components comp, the attributes attr of the object to which the reference in a line points can be used as key values for reading, sorting and changing table rows. This is possible in the following statements:

,,LOOP AT itab ... WHERE comp->attr ... 
,,READ TABLE itab ... WITH [TABLE] KEY comp->attr = ... 
<b>,,SORT itab BY comp->attr ...</b> 
,,DELETE itab WHERE comp->attr ... 
,,MODIFY itab ... TRANSPORTING ... WHERE comp->attr ...

<b>If a table contains unstructured lines with the type of a reference variable, the attributes of the object to which a line points can be addressed using TABLE_LINE->attr.</b>

</i>

Regards,

RIch Heilman

[daniel_humberg]

Tanks, Rich.

That's what I wanted.

I has something like this in mind, but I just couldn't find it in the doku.

Really cool!