What are User exits?

Question

Hi SAP gurus can u explain me on user exits?

Answer 1

Hi Chandrakanth,
Userexits are system modifications. The requirements of the client which can be met with Standard SAP are done with help of routines or userexits.
Userexits are nothing but a provision given by sap to write your own code/logic in the standard program.
Say for example while processing a sales order you want to check certain criteria weather they are met or not then you can use userxit_save_document_prepare.Here depending on the code you write system checks the if the criteria is fulfilling if not you can set an error or warning message in the code. This userexit is being executed just before saving of document.
one more commonly used exit is adding field in field catalog
In spro check this path Sales and Distribution-System modifications-Userexits.
Read the document provided,you will find all the exits in different processing for SD with program name and their purpose.
User exits are the enhancements provided by SAP
you can use them in transactions. Each transaction will have user exits.
If you want to use your own requirements by making your coding while the transaction is run you can use user exits.
For example if you want to run the MRP in MD02 specific to MRP controller you can user exit.
Please also refer the document below.
USEREXIT
Userxits allow us to add our own functionality to SAP standard program
without modifying it. These are implemented in the form of subroutines and hence are also known as FORM EXITs. The userexits are generally collected in includes and attached to the standard program by the SAP.
All Userexits start with the word USEREXIT_...
FORM USEREXIT_..
z..
ENDFORM.
The problem lies in finding the correct userexit and how to find it if one exists for the purpose. Once the correct userexit is found the necessary customer code is inserted in the customer include starting with the z. in the form routine.
e.g. USEREXIT_SAVE_DOCUMENT_PREPARE
Certain application like SD still provide this form of enhancement using userexit but this practice is no longer being followed for newer extensions instead they are using EXITs which come bundled in enhancement packages . Nevertheless existing USEREXITS will be supported by SAP an all the newer versions of SAP.
HOW TO FIND USEREXITS
Userexits can be found in number of ways:
1) To find userexits in SD module , goto object navigator(SE80) and select
development class from the list and enter VMOD in it. All of the userexits in SD are contained in the development class VMOD. Press enter and you will find all the includes which contain userexits in SD for different functions like PRICING, ORDER PROCESSING etc. Select the userexit according to the requirement and read the comment inserted in it and start coding.
Some examples of userexits in SD (SALES & DISTRIBUTION) are:
1)ADDING OF NEW FIELDS IN PRICING
In Pricing in SD the fields on the basis of which pricing is done are derived from the FIELD CATALOG which is a structure KOMG .This structure is used to transfer transaction data to the pricing procedure in SD and is also known as communication structure. This structure KOMG consists of two tables KOMK for Header related fields and KOMP for item related fields. The fields which are not in either of the two tables KOMK and KOMP cannot be used in pricing .Sometimes a need arises when the pricing is to be based on some other criteria which is not present in the form of fields in either of the two tables. This problem can be solved by using USEREXITS which are provided for pricing in SD. Pricing takes place both when the SALES ORDER ( Transaction VA01) is created as well as when INVOICING ( Transaction VF01) is done. Hence SAP provides 2 userexits ,one for sales order processing which is
USEREXIT_PRICING_PREPARE_TKOMP or
USEREXIT_PRICING_PREPARE_TKOMK
Depending upon which table (KOMK or KOMP) the new fields were inserted we use either of the above two userexits.These userexits are found in include MV45AFZZ of the standard SAP sales order creation program SAPMV45A.
In the case of userexit which will be called when invoicing is done ,these
are provided in the include RY60AFZZ which is in the standard SAP program SAPMV45A. The name of the userexits are same. i.e.
USEREXIT_PRICING_PREPARE_TKOMP or
USEREXIT_PRICING_PREPARE_TKOMK
These userexits are used for passing the data from the communication structure to the pricing procedure, for this we have to fill the newly created field in the communication structure KOMG for this we fill the code in the above userexit using the MOVE statement after the data that has to be passed is taken from the database table by using the SELECT statement. The actual structure which is visible in these userexits and which is to be filled for that particular field is TKOMP or TKOMK.
Before the coding for these userexits is done ,it is necessary to create a new field in either of the two tables KOMK or KOMP .For this purpose includes are provided in each of them .
To create the field in header data (KOMK) the include provided is KOMKAZ
and to create the field in item data (KOMP) the include provided is KOMPAZ.
One possible example for the need of creating new fields can be e.g. Freight to be based upon transportation zone, for this no field is available in field catalog and hence it can be created in KOMK and then above userexits can be used to fill the transportation data to it.
2) The other method of finding userexit is to find the word USEREXIT in the
associated program of the transaction for which we want to determine userexit using SE38.
3) The other method of finding userexits is to find the include in case of SD/MM applications where the userexits are located, this can be found in the SAP reference IMG generally in the subfolder under SYSTEM MODIFICATION.
Some other examples of userexits in SD are:
USEREXIT_NUMBER_RANGE
This userexit is used to assign a different internal document number to the
sales order(VA01) when it is created depending on some criteria like a different SALES ORGANIZAION(VKORG) .
USEREXIT_SAVE_DOCUMENT_PREPARE
This userexit is used to insert the ABAP code which will be called when
the document (sales order VA01) is just about to be saved. This userexit is used generally for custom checks on different fields , to display some information before the order will be saved or for making changes to certain fields before the sales order will be saved.
Exits & Enhancements
There are mainly six types of EXITs in sap which have been collected in the form of enhancement packages and attached to standard code in SAP.
These are different from USEREXIT in the way that they are implemented
in the form of FUNCTIONs while in USEREXITS we use form routines for their implementation. These are also sometimes known as function exits.
These start from the word EXIT_ followed by the program name and then followed by a three digit number.
e.g. EXIT_SAPMV45A_002
This exit is found in SD in enhancement V45A0002.
TYPES OF EXITS
1) MENU EXITS
2) FUNCTION EXITS
3) TABLE EXITS
4) SCREEN EXITS
5) KEYWORD EXITS
6) FIELD EXITS
We use SAP transactions CMOD and SMOD to manage exits. Before implementing an exit, it is required to create the project by using CMOD
selecting the enhancement e.g. V45A0002 and selecting the component
(one which fulfills our need) i.e. the exit which will be implemented in SMOD and after coding has been done the project has to be activated.
An exit can be coded only once.
FUNCTION EXITS
These are used to add functionality through ABAP code. These start from the word EXIT_programname_NNN ending in a 3 digit number. No access code is required to implement any type of exit including function exits.
The function exits are called from the standard SAP program in the form
of ABAP statement
CALL CUSTOMER-FUNCTION 'NNN'
This is in contrast to USEREXITs where PERFORM statement is used to call
the required userexit.
To implement the FUNCTION EXITs first of all the project is created and a suitable enhancement package is selected and from its components the function exit to be implemented is selected and on double clicking it the exit code will appear in ABAP EDITOR(se38) where a Z include will be found and the customer code should be entered in this include.
e.g.
ADDING A DEFAULT SOLD-TO-PARTY in Sales Order Creation
To show a default sold-to-party in this field when the user creates a sales order (VA01) we can use a function exit .This function exit is located in enhancement no V45A0002 . Before we can choose the exit we have to create a project in CMOD after that enter V45A0002 in the enhancement field and click on the components. In the components you will see the exit EXIT_SAPMV45A_002. This exit is used for our purpose.
Double clicking on this exit will takes us to function builder (SE37) . This
function exit has one exporting parameters and two importing parameters, we are interested in exporting parameter which is E_KUNNR of type KNA1-KUNNR i.e. if we move the desired customer name to this structure(E_KUNNR) it will be shown in the field as the default value when we create the sales order. This function also contains a customer include ZXVVA04. This include will be used to write our custom code.
Double clicking on this include and it will prompt us that this include does not exists do you want to create this object, select yes and the include will be created .In this include we can write our own code that will fill the field E_KUNNR.
e.g. E_KUNNR = 301.
Activate the include and Activate the project. Now when ever the SALES ORDER will be created, sold-to-party field will come up with a predefined customer.
FIELD EXITS
The field exits are managed, created, activated through program RSMODPRF. The field exit is associated with a data element existing in ABAP dictionary and hence to the screen field using that data element.
The format of field exit is:
FIELD_EXIT_dataelement_A-Z or 0-9
If a particular screen and program name is not specified than the field exit will effect all the screens containing that data element.
The function module associated with field exit shows two parameters
INPUT and OUTPUT. Input parameter contains the data passed to the field exit when the field exit was invoked by the R/3, we can write our own code to change the output parameter depending upon our requirements.
Before the field exit can have any effect the system profile parameter
ABAP/FIELDEXIT in all the application servers should be set to YES
ABAP/FIELDEXIT = YES.
User exits in the SD orders. These are program names (SE38):
MV45ATZZ
For entering metadata for sales document processing. User-specific
metadata must start with "ZZ".
MV45AOZZ
For entering additional installation-specific modules for sales
document processing which are called up by the screen and run under
PBO (Process Before Output) prior to output of the screen. The
modules must start with "ZZ".
MV45AIZZ
For entering additional installation-specific modules for sales
document processing. These are called up by the screen and run under
PAI (Process after Input) after data input (for example, data
validation). The User exits in the SD orders. These are program names (SE38):
MV45ATZZ
For entering metadata for sales document processing. User-specific
metadata must start with "ZZ".
MV45AOZZ
For entering additional installation-specific modules for sales
document processing which are called up by the screen and run under
PBO (Process before Output) prior to output of the screen. The
modules must start with "ZZ".
MV45AIZZ
For entering additional installation-specific modules for sales
document processing. These are called up by the screen and run under
PAI (Process after Input) after data input (for example, data
validation). The modules must start with "ZZ".
MV45AFZZ and MV45EFZ1
for entering installation-specific FORM routines and for using user
exits, which may be required and can be used if necessary. These
program components are called up by the modules in MV45AOZZ or
MV45AIZZ. e modules must start with "ZZ".
MV45AFZZ and MV45EFZ1
for entering installation-specific FORM routines and for using user
exits, which may be required and can be used if necessary. These
program components are called up by the modules in MV45AOZZ or
MV45AIZZ.
SMOD is the transaction to view user exits assigned to an object.
CMOD is the transaction to change the user exits according to your requirement.
You can find user exits by looking into the phrase USER_EXIT.
Check this program to find out user exits for a transaction
TABLES: tftit,
e071,
e070.
TYPES: BEGIN OF x_tstc,
tcode TYPE tcode,
pgmna TYPE program_id,
END OF x_tstc.
TYPES: BEGIN OF x_tadir,
obj_name TYPE sobj_name,
devclass TYPE devclass,
END OF x_tadir.
TYPES: BEGIN OF x_slog,
obj_name TYPE sobj_name,
END OF x_slog.
TYPES: BEGIN OF x_final,
name TYPE smodname,
member TYPE modmember,
include(15), "Include name
END OF x_final.
DATA: it_tstc TYPE STANDARD TABLE OF x_tstc WITH HEADER LINE.
DATA: it_tadir TYPE STANDARD TABLE OF x_tadir WITH HEADER LINE.
DATA: it_jtab TYPE STANDARD TABLE OF x_slog WITH HEADER LINE.
DATA: it_final TYPE STANDARD TABLE OF x_final WITH HEADER LINE.
SELECTION-SCREEN: BEGIN OF BLOCK blk01 WITH FRAME TITLE text-t01.
PARAMETERS: p_tcode LIKE tstc-tcode OBLIGATORY.
SELECTION-SCREEN END OF BLOCK blk01.
START-OF-SELECTION.
PERFORM get_tcodes. "Get Tcodes
PERFORM get_objects. "Get Objects
END-OF-SELECTION.
PERFORM display_results. "Display Results
FORM get_tcodes.
SELECT tcode
pgmna
INTO TABLE it_tstc
FROM tstc
WHERE tcode = p_tcode.
IF sy-subrc = 0.
SORT it_tstc BY tcode.
ENDIF.
ENDFORM. " get_tcodes
FORM get_objects.
DATA: l_fname LIKE rs38l-name,
l_group LIKE rs38l-area,
l_include LIKE rs38l-include,
l_namespace LIKE rs38l-namespace,
l_str_area LIKE rs38l-str_area.
DATA: v_include LIKE rodiobj-iobjnm.
DATA: e_t_include TYPE STANDARD TABLE OF abapsource WITH HEADER LINE.
DATA: l_line TYPE string,
l_tabix LIKE sy-tabix.
IF NOT it_tstc[] IS INITIAL.
SELECT obj_name
devclass
INTO TABLE it_tadir
FROM tadir FOR ALL ENTRIES IN it_tstc
WHERE pgmid = 'R3TR' AND
object = 'PROG' AND
obj_name = it_tstc-pgmna.
IF sy-subrc = 0.
SORT it_tadir BY obj_name devclass.
SELECT obj_name
INTO TABLE it_jtab
FROM tadir FOR ALL ENTRIES IN it_tadir
WHERE pgmid = 'R3TR' AND
object = 'SMOD' AND
devclass = it_tadir-devclass.
IF sy-subrc = 0.
SORT it_jtab BY obj_name.
ENDIF.
ENDIF.
ENDIF.
*- Get UserExit names
LOOP AT it_jtab.
SELECT name
member
INTO (it_final-name, it_final-member)
FROM modsap
WHERE name = it_jtab-obj_name AND
typ = 'E'.
APPEND it_final.
CLEAR it_final.
ENDSELECT.
ENDLOOP.
*- Process it_final contents.
LOOP AT it_final.
l_tabix = sy-tabix.
CLEAR: l_fname,
l_group,
l_include,
l_namespace,
l_str_area.
l_fname = it_final-member.
CALL FUNCTION 'FUNCTION_EXISTS'
EXPORTING
funcname = l_fname
IMPORTING
group = l_group
include = l_include
namespace = l_namespace
str_area = l_str_area
EXCEPTIONS
function_not_exist = 1
OTHERS = 2.
IF sy-subrc = 0.
IF NOT l_include IS INITIAL.
*- Get Source code of include.
CLEAR: v_include, e_t_include, e_t_include[].
v_include = l_include.
CALL FUNCTION 'MU_INCLUDE_GET'
EXPORTING
i_include = v_include
TABLES
e_t_include = e_t_include.
IF sy-subrc = 0.
LOOP AT e_t_include.
IF e_t_include-line CS 'INCLUDE'.
CLEAR l_line.
l_line = e_t_include-line.
CONDENSE l_line NO-GAPS.
TRANSLATE l_line USING '. '.
l_line = l_line+7(9).
it_final-include = l_line.
MODIFY it_final INDEX l_tabix TRANSPORTING include.
ENDIF.
ENDLOOP.
ENDIF.
ENDIF.
ENDIF.
ENDLOOP.
ENDFORM. " get_objects
FORM display_results.
FORMAT COLOR COL_HEADING.
WRITE:/1(150) sy-uline.
WRITE:/ sy-vline,
2(23) 'Extension Name',
24 sy-vline,
25(39) 'Exit Name',
64 sy-vline,
65(74) 'Description',
140 sy-vline,
141(9) 'Include',
150 sy-vline.
WRITE:/1(150) sy-uline.
FORMAT RESET.
SORT it_final BY name member.
LOOP AT it_final.
CLEAR tftit.
SELECT SINGLE stext
INTO tftit-stext
FROM tftit
WHERE spras = 'EN' AND
funcname = it_final-member.
WRITE:/ sy-vline,
it_final-name COLOR COL_KEY, 24 sy-vline,
25 it_final-member, 64 sy-vline,
65 tftit-stext, 140 sy-vline,
141 it_final-include, 150 sy-vline.
WRITE:/1(150) sy-uline.
ENDLOOP.
ENDFORM. " display_results
Hope this Clarifies your Doubts and Please Reward If Really Helpful,
Thanks and Regards,
Sateesh.Kandula