DATA - REF TO
Short Reference
ABAP Syntax_3 DATA ref { {TYPE REF TO type}
| {LIKE REF TO dobj} }
[VALUE IS INITIAL]
[READ-ONLY] .
What does it do? The addition REF TO declares a reference variable
ref . The entry behind REF TO specifies the static type of
the reference variable. The static type limits the set of objects to
which ref can point. The dynamic type of a reference variable is
the data type or the class to which it currently points. The static type
is always more general or the same as the dynamic type (see also
conversion rule for reference variables).
The syntax and meaning of the additions TYPE and LIKE
are the same as the definition of reference types in the section
TYPES - REF TO , but here they
are used to create a bound reference type.
Only IS INITIAL can be specified as a
start value after the addition
VALUE .
Latest notes: Reference variables are opaque, which means their content
cannot be accessed directly. A reference consists of the address of an
object and other administration information.
Example ABAP Coding In this example, an object reference oref and two
data references dref1 and dref2 are declared. Both data
references are typed fully and can be dereferenced using the
dereferencing operator - * in operand positions.
CLASS c1 DEFINITION.
PUBLIC SECTION.
DATA a1 TYPE i VALUE 1.
ENDCLASS.
DATA: oref TYPE REF TO c1,
dref1 LIKE REF TO oref,
dref2 TYPE REF TO i.
CREATE OBJECT oref.
dref1 = REF #( oref ).
CREATE DATA dref2.
dref2->* = dref1->*->a1.
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