REPORT AA.
TYPES: BEGIN OF T_LINE,
COL1 TYPE CHAR5,
COL2 TYPE CHAR10,
COL3 TYPE CHAR15,
END OF T_LINE.
DATA: GV_ADDR(30) TYPE C VALUE 'CHINA BEIJING TWIN BUILDING'.
FIELD-SYMBOLS: <FS> TYPE T_LINE.
"若不使用Casting,则会产生数据类型不一致的错误，因为是结构类型，gv_addr是字符类型。
ASSIGN GV_ADDR TO <FS> CASTING.
WRITE:/ <FS>-COL1, <FS>-COL2, <FS>-COL3.
FIELD-SYMBOLS:<FS1> TYPE ANY.
ASSIGN GV_ADDR TO <FS1> CASTING TYPE T_LINE.
WRITE:/ <FS>-COL1, <FS>-COL2, <FS>-COL3.
CLASS VEHICLE DEFINITION .
PUBLIC SECTION.
METHODS:DRIVE.
PROTECTED SECTION.
DATA:SPEED TYPE I VALUE '100'.
ENDCLASS.
CLASS PLAN DEFINITION INHERITING FROM VEHICLE.
PUBLIC SECTION.
METHODS:FLY.
ENDCLASS.
CLASS VEHICLE IMPLEMENTATION.
METHOD DRIVE.
SPEED = SPEED + 100.
WRITE:/ 'Driving is possible,','Current Speed:',SPEED.
ENDMETHOD.
ENDCLASS.
CLASS PLAN IMPLEMENTATION.
METHOD: FLY.
SPEED = SPEED + 1000.
ENDMETHOD.
ENDCLASS.
START-OF-SELECTION.
DATA:CAR TYPE REF TO VEHICLE.
DATA:AIR TYPE REF TO VEHICLE.
DATA:AIR1 TYPE REF TO VEHICLE.
DATA:AIR2 TYPE REF TO VEHICLE.
CREATE OBJECT:CAR. "里面的初始speed是100
CREATE OBJECT:AIR1."里面的初始speed是100
AIR2 = CAR."里面的初始speed是200 ，相当于已经执行一遍的CAR
AIR ?= CAR."里面的初始speed是100 相当于根据类创建了一个与CAR相同的实例
CALL METHOD AIR->DRIVE( ).
CALL METHOD AIR1->DRIVE( ).
CALL METHOD AIR2->DRIVE( ).
