Collection in ABAP

Question

Hello Friends,
Is there some kind of collection or Array concept in ABAP, Like in JAVA ( Java.util.Collection)??
In loop I want to take values 1 by 1 and store it in some kind of collection ??
Many thanks
Marek

Answer 1

Hi Marek
As Suekrue stated, in ABAP the closest concept to an "array" is an "internal table". You can think of them as structured and semanticly-defined matrices. They are like database tables, but are not persistent i.e their lifetime is the programs' runtime.
You can define an internal table in various ways.
<u><b>e.g.</b></u>
DATA: BEGIN OF gt_itab OCCURS 0 ,
        <colmun_1> LIKE/TYPE <data_element/variable> ,
        <colmun_2> LIKE/TYPE <data_element/variable> ,
        <colmun_n> LIKE/TYPE <data_element/variable> ,
      END OF gt_itab .
With this data declaration, you define an internal table having n columns and several rows (row number is not indicated).
Alternatively, you can define internal table type at data dictionary and refer to them as
DATA gt_itab TYPE <DDIC_table_type> .
or you can refer a structure to be the row-type of an internal table as:
DATA gt_itab LIKE <DDIC_structure> OCCURS 0 .
However, reaching to specific records is not done directly indicating the coordinate. You read rows to a work area and reach its field by "-" operator.
<b><u>e.g.</u></b>
READ TABLE gt_itab INTO gs_itab INDEX 5 . "read fifth row"
WRITE:/ gt_itab-<column_name> .
For more information, I strongly recommend you to inspect SAP Online Help whose address was mentioned at Sidharth's post and the book
<a href="http://www.sap-press.com/product.cfm?account=&product=H958">"ABAP Objects — The Official Reference" A comprehensive guide to all ABAP language elements</a>
by Horst Keller & Joachim Jacobitz
or
"ABAP Objects: Introduction to Programming SAP Applications" by Horst Keller, Sascha Kruger.
*--Serdar
Message was edited by: Serdar Simsekler