1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
|
{ test code based on code from ttp://www.geocities.com/svi37/cyber/delphi9/iimplementation.html }
{$ifdef fpc}
{$mode delphi}
{$endif fpc}
uses
sysutils;
type
IXInterface = interface(IUnknown)
['{713252E5-4636-11D5-B572-00AA00ACFD08}']
procedure XStaticMethod;
procedure XVirtualMethod;
end;
IYInterface = interface(IUnknown)
['{713252E6-4636-11D5-B572-00AA00ACFD08}']
procedure YMethod;
end;
IZInterface = interface(IUnknown)
['{713252E4-4636-11D5-B572-00AA00ACFD08}']
end;
type
TInnerObject = class(TAggregatedObject,IXInterface,IYInterface)
public
procedure XStaticMethod;
procedure XVirtualMethod; virtual;
procedure YMethod;
end;
TSpecialObject = class(TInnerObject,IXInterface,IYInterface)
public
procedure XStaticMethod;
procedure XVirtualMethod; override;
procedure YMethod;
end;
TFoo = class({!!!! IXInterface, }IYInterface,IZInterface)
private
FInnerX: TInnerObject;
protected
function QueryInterface(constref IID: TGUID; out Obj): HResult; virtual; {$IFNDEF WINDOWS}cdecl{$ELSE}stdcall{$ENDIF};
function _AddRef: Integer; {$IFNDEF WINDOWS}cdecl{$ELSE}stdcall{$ENDIF};
function _Release: Integer; {$IFNDEF WINDOWS}cdecl{$ELSE}stdcall{$ENDIF};
function GetX: TInnerObject; virtual;
function GetY: IYInterface;
public
constructor Create;
destructor Destroy; override;
//!!!! property InnerX: TInnerObject read GetX implements IXInterface;
property InnerY: IYInterface read GetY implements IYInterface;
end;
TBar = class(TFoo,{!!!!IXInterface,}IYInterface,IUnknown)
private
FX: TSpecialObject;
FY: IYInterface;
protected
function GetX: TInnerObject; override;
public
constructor Create;
destructor Destroy; override;
property Y: IYInterface read FY implements IYInterface;
//!!!! property X: TSpecialObject read FX implements IXInterface;
end;
{ TFoo }
constructor TFoo.Create;
var
i: IZInterface;
begin
inherited;
i := self;
FInnerX := TInnerObject.Create(i); //interface inh. to IUnknown
end;
destructor TFoo.Destroy;
begin
WriteLn('TFoo.Destroy');
FInnerX.Free;
inherited;
end;
{ TFoo.IUnknown }
function TFoo._AddRef: Integer;
begin
result := -1;
end;
function TFoo._Release: Integer;
begin
result := -1;
end;
function TFoo.QueryInterface(constref IID: TGUID; out Obj): HResult;
begin
if GetInterface(IID, Obj) then Result := 0 else Result := E_NOINTERFACE;
end;function TFoo.GetX: TInnerObject;
begin
result := FInnerX;
end;
{ TFoo.IUnknown }
function TFoo.GetY: IYInterface;
begin
result := FInnerX;
end;
{ TBar }
constructor TBar.Create;
begin
inherited;
FX := TSpecialObject.Create(Self); //explicit IUnknown
FY := FX;
end;
destructor TBar.Destroy;
begin
WriteLn('TBar.Destroy');
FY := nil;
FX.Free;
inherited;
end;
function TBar.GetX: TInnerObject;
begin
result := FX;
end;
{ TInnerObject }
procedure TInnerObject.XStaticMethod;
begin
WriteLn(Format(
'Calls TInnerObject.XStaticMethod on a %s',[ClassName]));
end;
procedure TInnerObject.XVirtualMethod;
begin
WriteLn(Format(
'Calls TInnerObject.XVirtualMethod on a %s',[ClassName]));
end;
procedure TInnerObject.YMethod;
begin
WriteLn(Format(
'Calls TInnerObject.YMethod on a %s',[ClassName]));
end;
{ TSpecialObject }
procedure TSpecialObject.XStaticMethod;
begin
WriteLn(Format(
'Calls TSpecialObject.XStaticMethod on a %s',[ClassName]));
end;
procedure TSpecialObject.XVirtualMethod;
begin
// inherited;
WriteLn(Format(
'Calls TSpecialObject.XVirtualMethod on a %s',[ClassName]));
end;
procedure TSpecialObject.YMethod;
begin
WriteLn(Format(
'Calls TSpecialObject.YMethod on a %s',[ClassName]));
end;
procedure TestFoo(AFoo: TFoo);
var
o: TFoo;
x: IXInterface;
y: IYInterface;
z: IZInterface;
begin
o := AFoo;
//!!!! x := o;
//!!!! x.XStaticMethod; // if AFoo is TBar TFoo.XStatic hides TBar.XStatic
//!!!! x.XVirtualMethod;
y := o;
y.YMethod;
//!!!! z := x as IZInterface;
z := y as IZInterface;
z := o;
//!!!! x := z as IXInterface;
end;
procedure TestBar(ABar: TBar);
var
o: TBar;
x: IXInterface;
y: IYInterface;
z: IZInterface;
begin
o := ABar;
//!!!! x := o;
//!!!! x.XStaticMethod;
//!!!! x.XVirtualMethod;
y := o;
y.YMethod;
//!!!! z := x as IZInterface;
z := y as IZInterface;
z := o;
//!!!! x := z as IXInterface;
end;
procedure Test;
var
AFoo: TFoo;
ABar: TBar;
begin
AFoo := TFoo.Create;
ABar := TBar.Create;
WriteLn('***TestFoo(AFoo)*****************');
TestFoo(AFoo);
WriteLn('***TestFoo(ABar)*****************');
TestFoo(ABar);
WriteLn('***TestBar(ABar)*****************');
TestBar(ABar);
AFoo.Free;
ABar.Free;
end;
begin
WriteLn('IntGetter.TInnerObject.InstanceSize: ',TInnerObject.InstanceSize);
WriteLn('IntGetter.TSpecialObject.InstanceSize: ',TSpecialObject.InstanceSize);
WriteLn('IntGetter.TFoo.InstanceSize: ',TFoo.InstanceSize);
WriteLn('IntGetter.TBar.InstanceSize: ',TBar.InstanceSize);
Test;
end.
|
