工作生活与爱好

Report Z_CTRY.

* A Shape Interface "Like a shape" "Behaves like a Shape"
Adverb/Adjective

Interface IShape.
Methods:  getArea Returning Value(area) Type F,
          getCircumference Returning Value(circumference) Type F.
Endinterface.

* A Circle Class that behaves like a Shape
Class CCircle Definition.

    Public Section.

        Interfaces IShape.

        Aliases:   getArea For IShape~getArea,
                   getCircumference For IShape~getCircumference.

        Methods:   Constructor Importing pRadius Type F,
                   setRadius   Importing pRadius Type F,
                   getRadius   Returning Value(pRadius) Type F.

    Private Section.
        Data radius Type F.
        Constants PI Type F Value '3.141592365359'.
EndClass.

Class CCircle Implementation.

    Method Constructor.
        radius = pRadius.
    EndMethod.

    Method setRadius.
        radius = pRadius.
    EndMethod.

    Method getRadius.
        pRadius = radius.
    EndMethod.

    Method IShape~getArea.
        Compute area = 2 * PI * radius.
    EndMethod.

    Method IShape~getCircumference.
        Compute circumference = PI * radius * radius.
    EndMethod.

EndClass.

* A Square Class
Class CSquare Definition.

    Public Section.

        Interfaces IShape.

        Aliases:   getArea For IShape~getArea,
                   getCircumference For IShape~getCircumference.

        Methods:   Constructor Importing pSide Type F.

    Private Section.
        Data side Type F.
EndClass.

Class CSquare Implementation.

    Method Constructor.
        side = pSide.
    EndMethod.

    Method IShape~getArea.
        Compute area = side * side.
    EndMethod.

    Method IShape~getCircumference.
        Compute circumference = 4 * side.
    EndMethod.

EndClass.

* A Rectangle Class
Class CRectangle Definition.

    Public Section.

        Interfaces IShape.

        Aliases:   getArea For IShape~getArea,
                   getCircumference For IShape~getCircumference.

        Methods:   Constructor Importing pHeight Type F
                                         pLength Type F.

    Private Section.
        Data: height Type F,
              length Type F.
EndClass.

Class CRectangle Implementation.

    Method Constructor.
        height = pHeight.
        length = pLength.
    EndMethod.

    Method IShape~getArea.
        Compute area = height * length.
    EndMethod.

    Method IShape~getCircumference.
        Compute circumference = 2 * ( height + length ).
    EndMethod.

EndClass.

* START of PROGRAM

* Array of Shapes
Data:  OneShape   Type Ref To IShape,             " One Object with
Shape Behaviour
       ShapeTable Type Table Of Ref To IShape.    " Array of Objects
with Shape Behaviour

* Concrete Objects with IShape Behaviour!
Data:  C1 Type Ref To CCircle,
       S1 Type Ref To CSquare,
       R1 Type Ref To CRectangle,
       C2 Type Ref To CCircle,
       S2 Type Ref To CSquare,
       R2 Type Ref To CRectangle.


Data:  descr_ref  TYPE ref to CL_ABAP_TYPEDESCR,
       ClassName  Type String,
       Serial     Type I.

Data:  myArea          Type F,
       myCircumference Type F.

START-OF-SELECTION.
    Create Object C1 Exporting pRadius = '2.5'.
    Create Object C2 Exporting pRadius = '5.0'.

    Create Object S1 Exporting pSide = '3.5'.
    Create Object S2 Exporting pSide = '6.0'.

    Create Object R1 Exporting pHeight = '2.8' pLength = '3.4'.
    Create Object R2 Exporting pHeight = '1.7' pLength = '6.3'.

* Append in any order!
    Append S1  to ShapeTable.
    Append R2  to ShapeTable.
    Append R1  to ShapeTable.
    Append C2  to ShapeTable.
    Append C1  to ShapeTable.
    Append S2  to ShapeTable.

    Serial = 0.

    Loop At ShapeTable into OneShape.
       Call Method OneShape->getArea
                             Receiving area = myArea.
       Call Method OneShape->getCircumference
                             Receiving circumference = myCircumference.

       descr_ref = CL_ABAP_TYPEDESCR=>Describe_By_Object_Ref( OneShape
).
       Call Method descr_ref->get_relative_name
                   Receiving P_RELATIVE_NAME = ClassName.

       Add 1 to Serial.

       Write: / Serial,  ClassName.
       Write: / 'Area          ',  myArea          Decimals 4 Exponent
0.
       Write: / 'Circumference ',  myCircumference Decimals 4 Exponent
0.
       Write: /.

    EndLoop.

** Results   
*           1  CSQUARE                       
*  Area                            12.2500   
*  Circumference                   14.0000   
*                                            
*           2  CRECTANGLE                    
*  Area                            10.7100   
*  Circumference                   16.0000   
*                                            
*           3  CRECTANGLE                    
*  Area                             9.5200   
*  Circumference                   12.4000   
*                                            
*           4  CCIRCLE                       
*  Area                            31.4159   
*  Circumference                   78.5398   
*                                            
*           5  CCIRCLE                       
*  Area                            15.7080   
*  Circumference                   19.6350   
*                                            
*           6  CSQUARE                       
*  Area                            36.0000   
*  Circumference                   24.0000

posted by lxy  # 23:13