topic Function Modules as Methods in Application Development and Automation Discussions

Function Modules as Methods

prasad_reddy9 — Thu, 28 Jun 2007 03:13:20 GMT

I want to call few FM as methods. ANyone has ANy sample example for it?

Re: Function Modules as Methods

Former Member — Thu, 28 Jun 2007 05:30:59 GMT

Hi Prasad,

Syntactical constraints will not allow you to call function modules as methods. What you can do is define some methods in a class and inside the method implementation just call the FM in the same way as you call it from some other place. Then call the method using the syntax used for calling methods.

CLASS zl_lcl_vehicle DEFINITION.

PUBLIC SECTION.

METHODS: set_make

IMPORTING im_make TYPE string

im_model TYPE string.

ENDCLASS. "zl_lcl_vehicle DEFINITION

CLASS zl_lcl_vehicle IMPLEMENTATION.

METHOD set_make.

call function <FM name>.

ENDMETHOD. "set_make

ENDCLASS. "zl_lcl_vehicle

START-OF-SELECTION.

Create instance of the vehicle class

CREATE OBJECT z_vehicle1.

Normal Syntax for method calls

CALL METHOD: z_vehicle1->set_make EXPORTING im_make = 'HYUNDAI'

im_model = 'SANTRO'.

<b>Award points if found useful.</b>

Regards

Indrajit

Re: Function Modules as Methods

prasad_reddy9 — Thu, 28 Jun 2007 05:53:54 GMT

Thx for the reply.

Just few clarifications...

So, the importing, exporting and changing parameters of the FM must match the Methods.

What abt 'table' option option?

DO we handle handle exceptions as events or just let the called FM raise its own messages?

Re: Function Modules as Methods

Former Member — Thu, 28 Jun 2007 06:02:44 GMT

Hi Prasad,

What you can do is -

Import a parameter in method - Export it to FM if required

Import a parameter from FM - Use it in the method if required.

The table option is for importing/exporting tables.

The function module will handle the exceptions defined in its interface and return the value in sy-subrc. You can check it and code some functionality depending on the value of sy-subrc. This depends on your requirement. If the FM does not handle any exception that you want to handle, you can handle it explicitly using exception classes and TRY-CATCH statements.

Let me know if you need any further clarifications.

Award points if found useful.

Regards

Indrajit

Re: Function Modules as Methods

prasad_reddy9 — Thu, 28 Jun 2007 06:06:11 GMT

It is helpful.

Can u elaborate on the tables option?

I know how to use it in FM's but in classes how do u handle it, especially for passing it to the FM inside the method? Just declare it in changing type of the class?

Re: Function Modules as Methods

Former Member — Thu, 28 Jun 2007 06:36:03 GMT

Hi Prasad,

See the following piece of code.

TYPES: ty_itab TYPE standard table OF sflight.

&----

*& Class (Definiton) zl_lcl_vehicle

&----

Definition of Vehicle class

----

CLASS zl_lcl_vehicle DEFINITION.

PUBLIC SECTION.

METHODS: set_make

IMPORTING value(im_itab) TYPE ty_itab.

PRIVATE SECTION.

DATA: gt_itab TYPE STANDARD TABLE OF sflight.

ENDCLASS. "zl_lcl_vehicle DEFINITION

&----

*& Class (Implementation) zl_lcl_vehicle

&----

Implementation of Vehicle class

----

CLASS zl_lcl_vehicle IMPLEMENTATION.

METHOD set_make.

CALL FUNCTION 'Z_MOBILE_NUMBER_DIST'

TABLES

t_in_slifght = im_itab.

ENDMETHOD. "set_make

ENDCLASS. "zl_lcl_vehicle

Declaring a reference variable with reference to the vehicle class.
This vareiable contains a reference to an object of theclass

DATA z_vehicle1 TYPE REF TO zl_lcl_vehicle.

DATA : gt_itab TYPE STANDARD TABLE OF sflight.

START-OF-SELECTION.

Create instance of the vehicle class

CREATE OBJECT z_vehicle1.

Normal Syntax for method calls

CALL METHOD: z_vehicle1->set_make EXPORTING im_itab = gt_itab.

_________________________________________________________________

<b>Award points if found useful.</b>

Regards

Indrajit

Re: Function Modules as Methods

prasad_reddy9 — Thu, 28 Jun 2007 07:18:30 GMT

Just tried it.

Seems FM may need to be called 'In Background Task' !!

And I cant seem to make the FM accpept importing parameters from the method.

Re: Function Modules as Methods

Former Member — Thu, 28 Jun 2007 07:21:38 GMT

Hi Prasad,

In the FM define a TABLES parameter and while calling the FM assign the table imported by the method to it.

Award points if useful.

Regards

Indrajit

Re: Function Modules as Methods

Former Member — Thu, 28 Jun 2007 11:45:38 GMT

> It is helpful.

> Can u elaborate on the tables option?

> I know how to use it in FM's but in classes how do u

> handle it, especially for passing it to the FM inside

> the method? Just declare it in changing type of the

> class?

short answer: yes

TABLES parameters are forbidden in OO context. You should not use them. They work only with STANDARD TABLE WITH HEADER LINE, which are forbidden in ABAP OO. Even when working with FMs you should not use them.

Re: Function Modules as Methods

prasad_reddy9 — Fri, 29 Jun 2007 03:51:21 GMT

We can always declare tables without header line. Thats not a problem I think.

I tried to do this and the FM inside the method was not accepting the input parameters from the method.

If Anyone has a sample code for this type of a thing, it would be of immense help.