1. ABAP Chapter 5
Modularization
Catch Statement

2. Modularization

3. Modularization Internal Subroutine Call External Subroutine Call
Function Module

4. Subroutine START-OF-SELECTION. Perfrom routine1. Perform routine2.
select * from customers into table tab.
Endform.
Form routine2.
loop at tab.
write: / tab-id,tab-name.
endloop. …

5. Modularization Avoid redundancy
Make your program easy to read & improve their structure
Re-use Program components

6. Calling and Defining Subroutines
REPORT ztest.
* Global Data
TABLES customers.
DATA tmp type i.
* Subroutine Calls
PERFORM routine1.
PERFORM routine2.
* Subroutine
FORM routine1.
DATA tmp1 type p. “Local data
write tmp.
ENDFORM.
FORM routine2.
DATA tmp2(10). “Local data
…..

7. Call by Value a1
Copy f1
Memory Space(Subroutine)

8. Call by Value Data: a1,a2. a1 = ‘A’. a2 = ‘A’.
PERFORM routine1 USING a1 a2.
.…...
FORM routine1 USING VALUE(f1) VALUE(f2).
f1 = ‘X’.
f2 = ‘X’.
ENDFORM.

9. Call by Reference a3
Address Passing f3
Memory Space(Subroutine)

10. Call by Reference Data: a3. a3 = ‘A’. PERFORM routine2 USING a3. .…...
FORM routine2 USING f3.
f3 = ‘X’.
ENDFORM.

11. Call by Value and Result
Copy
Copy f4
Memory Space(Subroutine)

12. Call by Value and Result
Data: a4,a5.
a4 = ‘A’.
a5 = ‘A’.
PERFORM routine3 USING a4 a5.
.…...
FORM routine3 CHANGING VALUE(f4) f5. “f5 : call by reference
f4 = ‘X’.
f5 = ‘X’.
ENDFORM.

13. Passing Structure as Parameters
TABLES sflight.
SELECT * FROM sflight.
PERFORM subproc USING sflight.
ENDSELECT.
FORM subproc USING rec LIKE sflight.
WRITE: / rec-carrid.
ENDFORM.

14. Passing Internal Table as Parameters
DATA: tab LIKE sflight OCCURS 0 WITH HEADER LINE. …
PERFORM sub TABLES tab.

15. Passing Internal Table as Parameters
FORM sub TABLES tab1 STRUCTURE tab.
LOOP AT tab1.
WRITE: / tab1-carrid.
ENDLOOP.
ENDFORM.

16. External Subroutines REPORT RSAAA10F. TABLES: sflight. …..
PERFORM cal(RSAAA10B).
REPORT RSAAA10B.
TABLES sflight.
FORM cal.
ENDFORM.

17. EXIT Statement DATA tmp TYPE I. tmp = 4. PERFORM a. WRITE tmp. FORM a.
ENDFORM.

18. STOP Statement DATA tmp TYPE I. START-OF-SELECTION. tmp = 4.
PERFORM a.
WRITE tmp.
END-OF-SELECTION.
tmp = 0.
write tmp.
FORM a.
STOP. “go to END-OF-SELECTION
tmp = 99.
ENDFORM.

19. Function Module

20. Function Module Function Group Function Library - Admin
- Import/Export Parameter
- Source Code
- Main Program
- Documentation

21. Function Group
When you create a function module, you must assign it to function group
The function group is the main program in which a function module is embedded
The function group is a program type F,and not executable
The entire function group is loaded in a program the first time that you call a function module that belongs to it

22. Function Group is a container for function modules
When a function module is called,the entire function group is loaded into the session of the program
Function group is used to define global data for function modules
A DATA statement in the global memory of a function group is shared by all the function modules that belong to that function group

23. Function Group : SE37

24. Function Group : SE80

25. Function Module
is a code that can be called from any ABAP program,therefore making it a globally accessible object
ABAP program pass data to function module from import parameters or internal tables
Function module receives data from a program,process the information in its own code, and then sends back information in the export parameters or internal tables

26. Function Module : SE37

27. Function Module

28. Function Module : Source Code
FUNCTION Z_FMTEST.
result = number1 ** number2.
ENDFUNCTION.

29. Program Example I REPORT ztest. PARAMETERS: no1 TYPE I, no2 TYPE I.
DATA result TYPE I.
START-OF-SELECTION.
CALL FUNCTION ‘Z_FMTEST’
EXPORTING
number1 = no1
number2 = no2
IMPORTING
result = result.
write: / result.

30. Exercise : Function Module
ABAP Program
Function Module ?

31. EXCEPTIONS

32. Function Module Function Z_CAL01.
if number1 > 9 and number2 > 9.
raise invalidnumber.
else.
result = number1 ** number2.
endif.
ENDFUNCTION.

33. Example II : Exceptions
REPORT ztest.
PARAMETERS: no1 TYPE I,
no2 TYPE I.
DATA result TYPE I.
START-OF-SELECTION.
CALL FUNCTION ‘Z_CAL01’
EXPORTING
number1 = no1
number2 = no2
IMPORTING
result = result
EXCEPTIONS
invalidnumber = 1.
IF sy-subrc <> 0.
write: / ‘Please enter number < 10’.
ELSE.
write: / result.
ENDIF.

34. Exercise : Exceptions
ABAP Program
Function Module ?

35. EXCEPTIONS VS AT SELECTION-SCREEN
REPORT ztest.
Parameters: no1 type i,
no2 type i.
At selection-screen
if no1 > 9 and no2 > 9.
message e000(38) with ‘Please enter no < 10’.
endif.
START-OF-SELECTION.
CALL FUNCTION ‘Z_CAL01’.
…..
FUNCTION Z_CAL01.
if number1 > 9 and number2 > 9.
raise invalidnumber.
else.
result = number1 ** number2.
endif.
ENDFUNCTION. VS

36. Optional
Function Module
ABAP Program

37. Structure in Function Module

38. Example : Structure

39. Example : Structure

40. Internal Table in Function Module

41. Example : Internal Table

42. Example : Internal Table

43. Function Module : Z_FMTEST Function Module : Z_CAL01
Function Group
Function Group : ZGRP00
Function Module : Z_FMTEST
Function Module : Z_CAL01

44. Function Group

45. Function Module in Function Group

46. Exercise
Display current month name using function module

47. Catch Statement

48. CATCH Statement Syntax
Catch system-exceptions <error type> = <n>.
<ABAP statement – generate runtime error> .
Endcatch.
if sy-subrc = <n>.
...
endif.

49. CATCH Error Type
Error class
Catch system-exceptions conversion_errors = 1.
Single error
Catch system-exceptions convt_no_number = 1.
All catchable runtime error
Catch system-exceptions others = 1.

50. CATCH Statement Report ztest. Data num type I.
Catch system-exceptions conversion_errors = 1.”others
Move ‘abc’ to num. “runtime error: convt_no_number
Endcatch.
If sy-subrc = 1.
Write: / ‘Assign wrong data type to variable: num’.
Endif.

51. CATCH Statement Report ztest. Data num type I.
Catch system-exceptions others = 1.
Move ‘abc’ to num.
Endcatch.
If sy-subrc = 1.
Write: / ‘Assign wrong data type to variable: num’.
Endif.

52. CATCH Statement Report ztest. PARAMETERS: NUM1 TYPE I, NUM2 TYPE I.
DATA RESULT TYPE I.
START-OF-SELECTION.
CATCH SYSTEM-EXCEPTIONS COMPUTE_INT_ZERODIVIDE = 1.
RESULT = NUM1 / NUM2.
ENDCATCH.
IF SY-SUBRC = 1.
WRITE: /'Divide by zero'.
ELSE.
WRITE: / RESULT.
ENDIF.

53. CATCH Statement Report ztest. PARAMETERS: NUM1 TYPE I, NUM2 TYPE I.
DATA RESULT TYPE I.
START-OF-SELECTION.
CATCH SYSTEM-EXCEPTIONS OTHERS = 1.
RESULT = NUM1 / NUM2.
ENDCATCH.
IF SY-SUBRC = 1.
WRITE: /'Divide by zero'.
ELSE.
WRITE: / RESULT.
ENDIF.

54. CATCH in Function Module
Function Z_CAL.
if number1 > 9 and number2 > 9.
raise invalidnumber.
else.
result = number1 ** number2.
endif.
ENDFUNCTION.
Function Z_CAL.
CATCH SYSTEM-EXCEPTIONS OTHERS = 1.
RESULT = NUMBER1 ** NUMBER2.
ENDCATCH.
IF SY-SUBRC = 1.
RAISE invalidnumber.
ENDIF.
ENDFUNCTION.

55. ABAP Practice