Reg: Contructor and methods

Question

Hi all
i am new to abap objects and i am going thro' the sap materials and i am facing some probelm in understanding the constructor part which is also  a type of method..can any one please let me know what is the difference between methods and constructors..
Your explanations are greatly welcome instead of links.
Thanks

Answer 1

Hi,
actualy constructor is a special method in OOABAP which is used for initialisation and it is always named as constructor.
Constructors are of 2 type 1. CLASS or Static Constructor
                                and 2 . Method Constructor.
Check the following code for the use and effect of both types of constructors
REPORT  demo_constructor_ANIRBAN.
      CLASS cl1 DEFINITION
CLASS cl1 DEFINITION.
  PUBLIC SECTION.
    METHODS:
      add,
      constructor IMPORTING v1 TYPE i
                            v2 TYPE i,
      display.
    CLASS-METHODS:
     class_constructor.
  PRIVATE SECTION.
    DATA:
    w_var1   TYPE i,
    w_var2   TYPE i,
    w_var3   TYPE i,
    w_result TYPE i.
ENDCLASS.                    "cl1 DEFINITION
      CLASS cl1 IMPLEMENTATION
CLASS cl1 IMPLEMENTATION.
  METHOD constructor.
    w_var1 = v1.
    w_var2 = v2.
  ENDMETHOD.                    "constructor
  METHOD class_constructor.
    WRITE:
    / 'Tihs is a class or static constructor.'.
  ENDMETHOD.                    "class_constructor
  METHOD add.
    w_result = w_var1 + w_var2.
  ENDMETHOD.                    "add
  METHOD display.
    WRITE:
    /'The result is =  ',w_result.
  ENDMETHOD.                    "display
endclass.
" Main program----
data:
  ref1 type ref to cl1.
parameters:
  w_var1 type i,
  w_var2 type i.
  start-of-selection.
  create object ref1 exporting v1 = w_var1
                              v2 = w_var2.
   ref1->add( ).
   ref1->d isplay( ).