* This program source contains all modules and subroutines of the
* flight reservation program, but screen and GUI status definitions
* are not included.
*&———————————————————————*

*&———————————————————————*
*& Include MSABBTOP Modulpool SAPMSABB *
*& *
*&———————————————————————*
PROGRAM SAPMSABB MESSAGE-ID SU.

* Database tables
TABLES:
PLANFLI, ” Flight connections
ACTFLI, ” Dates of flights
CUSTOMERS, ” Customer data
BOOKINGS. ” Booking informations

* User defined types
TYPES:
BOOLEAN TYPE C, ” true = ‘X’, false otherwise
SCREEN_CODE LIKE SY-DYNNR,
STATUS_CODE LIKE SY-PFKEY,
TITLEBAR_CODE(3) TYPE N,
FUNCTION_CODE(4) TYPE C.

DATA:
* Global data
FCODE TYPE FUNCTION_CODE,
FLAG_FOUND TYPE BOOLEAN,
FLAG_KEEP_INPUT TYPE BOOLEAN,

* Screen fields which do not come from the dictionary
SEATS_FREE TYPE I,
SEATS_REQUIRED TYPE I.

DATA:
* table of all customers
ALL_CUSTOMERS LIKE CUSTOMERS OCCURS 100
WITH HEADER LINE.

CONSTANTS:
* Boolean constants
TRUE TYPE C VALUE ‘X’,
FALSE TYPE C VALUE ‘ ‘,

* Screen codes
C_SCREEN_REQUEST TYPE SCREEN_CODE VALUE ‘0100′,
C_SCREEN_BOOKING TYPE SCREEN_CODE VALUE ‘0200′,

* Status codes
C_STATUS_REQUEST TYPE STATUS_CODE VALUE ‘REQUEST’,
C_STATUS_BOOKING TYPE STATUS_CODE VALUE ‘BOOKING’,
C_STATUS_LIST TYPE STATUS_CODE VALUE ‘LIST’,

* Titlebar codes
C_TITLE_REQUEST TYPE TITLEBAR_CODE VALUE ‘100′,
C_TITLE_BOOKING TYPE TITLEBAR_CODE VALUE ‘200′,
C_TITLE_LIST_CUSTOMERS TYPE TITLEBAR_CODE VALUE ‘110′,

* Function codes
C_FCODE_REQUEST TYPE FUNCTION_CODE VALUE ‘REQU’,
C_FCODE_BOOKING TYPE FUNCTION_CODE VALUE ‘BOOK’,
C_FCODE_CLEAR TYPE FUNCTION_CODE VALUE ‘CLEA’,
C_FCODE_BACK TYPE FUNCTION_CODE VALUE ‘BACK’,
C_FCODE_EXIT TYPE FUNCTION_CODE VALUE ‘EXIT’.

*———————————————————————–
***INCLUDE MSABBI01 .
*———————————————————————–

*&———————————————————————*
*& Module EXIT_SCREEN INPUT
*&———————————————————————*
* Handles back, exit, and clear command. *
*———————————————————————-*
MODULE EXIT_SCREEN INPUT.
CASE FCODE.
WHEN C_FCODE_Clear.
* Just clear the input fields
CASE SY-DYNNR.
WHEN c_screen_request. CLEAR: PLANFLI, ACTFLI.
WHEN C_SCREEN_BOOKING. CLEAR CUSTOMERS.
SEATS_REQUIRED = 1.
ENDCASE.
WHEN C_FCODE_BACK.
* Switch to previous screen.
CASE SY-DYNNR.
WHEN c_screen_request. SET SCREEN 0.
WHEN C_SCREEN_BOOKING. FLAG_KEEP_INPUT = FALSE.
SET SCREEN c_screen_request.
ENDCASE.
WHEN C_FCODE_EXIT.
* Exit program
SET SCREEN 0.
ENDCASE.
LEAVE SCREEN.
ENDMODULE. ” EXIT_SCREEN INPUT

*&———————————————————————*
*& Module ACTION_REQUEST INPUT
*&———————————————————————*
* Check input data to represent a valid flight connection. *
*———————————————————————-*
MODULE ACTION_REQUEST INPUT.
CASE FCODE.
WHEN C_FCODE_REQUEST.
* Check for a valid connection
PERFORM FLIGHT_REQUEST CHANGING FLAG_FOUND.

IF FLAG_FOUND = FALSE.
MESSAGE E001. ” Flight connection not available
ELSE.
SET SCREEN 200. ” Next screen: entering customer data
LEAVE SCREEN.
ENDIF.
ENDCASE.
ENDMODULE. ” ACTION_REQUEST INPUT

*&———————————————————————*
*& Module ACTION_BOOKING INPUT
*&———————————————————————*
* Get customer data to make the booking. *
*———————————————————————-*
MODULE ACTION_BOOKING INPUT.
CASE FCODE.
WHEN C_FCODE_BOOKING.
* Make the booking
PERFORM FLIGHT_BOOKING.

* Return to previous screen for another request.
FLAG_KEEP_INPUT = FALSE.
SET SCREEN C_SCREEN_REQUEST.
LEAVE SCREEN.
ENDCASE.
ENDMODULE. ” ACTION_BOOKING INPUT

*&———————————————————————*
*& Module VALUES_CUSTOMERS INPUT
*&———————————————————————*
* Display list of customers *
*———————————————————————-*
MODULE VALUES_CUSTOMERS INPUT.
* Display all customers in a dialog box
CALL SCREEN 110
STARTING AT 10 10
ENDING AT 30 20.
ENDMODULE. ” VALUES_CUSTOMERS INPUT

*&———————————————————————*
*& Module ACTION_LIST INPUT
*&———————————————————————*
* Write list of customers *
*———————————————————————-*
MODULE ACTION_LIST INPUT.

* Read all customers
SELECT * FROM CUSTOMERS INTO TABLE ALL_CUSTOMERS.

* Write all customers
NEW-PAGE NO-TITLE.
LOOP AT ALL_CUSTOMERS.
WRITE / ALL_CUSTOMERS-NAME.
HIDE ALL_CUSTOMERS-ID.
ENDLOOP.

ENDMODULE. ” ACTION_LIST INPUT

*——————————————————————-
***INCLUDE MSABBO01 .
*——————————————————————-

*&———————————————————————*
*& Module INIT_REQUEST OUTPUT
*&———————————————————————*
* Initializes titlebar and status of the screen for a flight *
* request. *
*———————————————————————-*
MODULE INIT_REQUEST OUTPUT.
* Initialize titlebar and status
SET TITLEBAR C_TITLE_REQUEST.
SET PF-STATUS C_STATUS_REQUEST.
ENDMODULE. ” INIT_REQUEST OUTPUT

*&———————————————————————*
*& Module INIT_BOOKING OUTPUT
*&———————————————————————*
* Initializes titlebar and status of the screen for a flight *
* request. The fields for the number of free and required seats *
* and for the customer’s data are initialized. *
*———————————————————————-*
MODULE INIT_BOOKING OUTPUT.
* Initialize titlebar and status
SET TITLEBAR C_TITLE_BOOKING.
SET PF-STATUS C_STATUS_BOOKING.

* Get number of seats free
SEATS_FREE = ACTFLI-SEATSMAX – ACTFLI-SEATSOCC.

* While processing the booking screen, the contents of the
* input fields are kept, e.g. if ENTER is pressed.
IF FLAG_KEEP_INPUT = FALSE.
CLEAR CUSTOMERS.
SEATS_REQUIRED = 1.
FLAG_KEEP_INPUT = TRUE. ” kept while processing the screen
ENDIF.
ENDMODULE. ” INIT_BOOKING OUTPUT
*&———————————————————————*
*& Module INIT_LIST OUTPUT
*&———————————————————————*
* Write list of customers *
*———————————————————————-*
MODULE INIT_LIST OUTPUT.

* Initialize titlebar and status
SET TITLEBAR C_TITLE_LIST_CUSTOMERS.
SET PF-STATUS C_STATUS_LIST.

* Prepare list
SUPPRESS DIALOG.
LEAVE TO LIST-PROCESSING AND RETURN TO SCREEN 0.

ENDMODULE. ” INIT_LIST OUTPUT

*——————————————————————-
***INCLUDE MSABBF01 .
*——————————————————————-

*&———————————————————————*
*& Form FLIGHT_REQUEST
*&———————————————————————*
* Check for a valid connection *
*———————————————————————-*
FORM FLIGHT_REQUEST CHANGING F_FLAG_FOUND TYPE BOOLEAN.

* First check for a valid connection, i.e. check if carrier CARRID
* offers a flight starting in city CITYFROM with destination CITYTO.
F_FLAG_FOUND = FALSE.
SELECT * FROM PLANFLI
WHERE CARRID = PLANFLI-CARRID
AND CITYFROM = PLANFLI-CITYFROM
AND CITYTO = PLANFLI-CITYTO.

* Then check if the connection is also offered for the
* specified date.
SELECT SINGLE * FROM ACTFLI
WHERE CARRID = PLANFLI-CARRID
AND CONNID = PLANFLI-CONNID
AND FLDATE = ACTFLI-FLDATE.
IF SY-SUBRC = 0.
F_FLAG_FOUND = TRUE.
EXIT.
ENDIF.
ENDSELECT.
ENDFORM. ” FLIGHT_REQUEST

*&———————————————————————*
*& Form FLIGHT_BOOKING
*&———————————————————————*
* Insert the booking into database tables *
*———————————————————————-*
FORM FLIGHT_BOOKING.

DATA: L_CUSTOMERS LIKE CUSTOMERS OCCURS 10
WITH HEADER LINE,
L_LINE_COUNT TYPE I,
L_INDEX LIKE SY-TABIX.

* 1. Check if seats are available
IF SEATS_REQUIRED > SEATS_FREE.
MESSAGE E003 WITH SEATS_FREE. ” Not enough seats
endif.

* 2. Booking is only allowed for registered customers. Thus,
* check if a customer id is available in table CUSTOMERS.
SELECT * FROM CUSTOMERS INTO TABLE L_CUSTOMERS
WHERE NAME = CUSTOMERS-NAME.

* Check number of matching entries
DESCRIBE TABLE L_CUSTOMERS LINES L_LINE_COUNT.
IF L_LINE_COUNT = 0.
message e004 with customers-name. ” Customer id not available
ELSEIF L_LINE_COUNT > 1.
* Process dialog to select the appropriate customer
… ” To be implemented: sets L_INDEX
endif.

L_INDEX = 1. ” Must be deleted if L_INDEX is set above
READ TABLE L_CUSTOMERS INDEX L_INDEX.
IF SY-SUBRC <> 0.
MESSAGE A006. ” Internal booking error: missing entry
ENDIF.

* 3. Update bookings information in table BOOKINGS
MOVE-CORRESPONDING ACTFLI TO BOOKINGS.
PERFORM SET_BOOKID CHANGING BOOKINGS-BOOKID.
BOOKINGS-CUSTOMID = L_CUSTOMERS-ID.
BOOKINGS-ORDER_DATE = SY-DATUM.

INSERT BOOKINGS. ” Optional: call function in update task
IF SY-SUBRC <> 0.
MESSAGE A005. ” Internal booking error: duplicate entries
ENDIF.

* 4. Update number of occupied seats in table ACTFLI
ADD SEATS_REQUIRED TO ACTFLI-SEATSOCC.
UPDATE ACTFLI. ” Optional: call function in update task
IF SY-SUBRC <> 0.
MESSAGE A006. ” Internal booking error: missing entry
ENDIF.

* Optional: using an update task
* call function ‘ABAP_BOOK_INSERT_BOOKINGS’
* in update task
* exporting
* i_bookings = bookings
* i_actfli = actfli.
* commit work.

* 5. Message: booking successful for customer …
MESSAGE I002 WITH ACTFLI-CONNID CUSTOMERS-NAME.

ENDFORM. ” FLIGHT_BOOKING

*&———————————————————————*
*& Form SET_BOOKID
*&———————————————————————*
* Determine a new booking id. *
*———————————————————————-*
FORM SET_BOOKID CHANGING F_BOOKID LIKE BOOKINGS-BOOKID.

* Get maximum bookid and increment it by 1
SELECT MAX( BOOKID ) INTO (F_BOOKID) FROM BOOKINGS.
ADD 1 TO F_BOOKID.
ENDFORM. ” SET_BOOKID

*——————————————————————-
***INCLUDE MSABBE01 .
*——————————————————————-

*&———————————————————————*
*& Event AT LINE-SELECTION
*&———————————————————————*

at line-selection.
* Get selected customer and display name
read table all_customers with key id = all_customers-id.
if sy-subrc = 0.
customers-name = all_customers-name.
endif.
leave to screen 0.

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