instance of

[Former Member]

I would like to know what is the equivalent in abap object of the "instance of" of Java, because I have an object upcasted and I want to know if i am able to downcast it, thanks

[Former Member]

Hello,

To downcast you can use the operator ?=.

This is an example:

DATA: ref1 TYPE REF TO object,
  ref2 TYPE REF TO class.

ref2 ?= ref1.

And to catch errors you can use the following.

CATCH SYSTEM-EXCEPTIONS move_cast_error = 4.
  ref2 ?= ref1.
ENDCATCH.
IF sy-subrc NE 0.
  WRITE 'Error when casting'.
ENDIF.

Regards,

[uwe_schieferstein]

Hello

On ECC 6.0 there is a static class method available which could be used as the InstanceOf equivalent.

*&---------------------------------------------------------------------*
*& Report  ZUS_SDN_IS_INSTANCE_OF
*&
*&---------------------------------------------------------------------*
*& Thread: instance of
*& <a class="jive_macro jive_macro_thread" href="" __jive_macro_name="thread" modifiedtitle="true" __default_attr="819410"></a>
*&---------------------------------------------------------------------*

REPORT  zus_sdn_is_instance_of.

TYPE-POOLS: abap.


DATA: go_msglist      TYPE REF TO cl_reca_message_list,
      gd_msg          TYPE bapi_msg.

PARAMETER:
  p_class   TYPE seoclsname  DEFAULT 'IF_RECA_MESSAGE_LIST'.


START-OF-SELECTION.

  go_msglist ?= cf_reca_message_list=>create( ).

  IF ( cl_wdy_wb_reflection_helper=>is_instance_of(
        object    = go_msglist
        type_name = p_class ) = abap_true ).
    concatenate 'Is instance of' p_class
      into gd_msg SEPARATED BY space.
    MESSAGE gd_msg TYPE 'I'.
  ELSE.
    concatenate 'Is NOT instance of' p_class
      into gd_msg SEPARATED BY space.
    MESSAGE gd_msg TYPE 'I'.
  ENDIF.


END-OF-SELECTION.

However, please note that this class may be only used in a rather restricted sense related to WebDynpro.

Regards

Uwe