C++的组合(Composite)模式

1 #include < list >
2 #include < iostream >
3 #include < string >
4
5   using namespace std;
6
7   class AbstractFile {
8 protected :
9 string name; /* 文件或目录名 */
10 public :
11 void printName() {cout << name << endl;} /* 打印文件或目录名称 */
12 virtual void addChild(AbstractFile * file) = 0 ; /* 给一个目录增加子目录或文件 */
13 virtual void removeChild(AbstractFile * file) = 0 ; /* 删除一个目录的子目录或文件 */
14 virtual list < AbstractFile *> * getChildren() = 0 ; /* 保存一个目录的子目录或文件 */
15 };
16
17 class File: public AbstractFile{
18 public :
19 File( string name) { this -> name = name;}
20 void addChild(AbstractFile * file) { return ;}
21 void removeChild(AbstractFile * file) { return ;}
22 list < AbstractFile *> * getChildren() { return NULL;}
23 };
24
25 class Folder: public AbstractFile {
26 private :
27 list < AbstractFile *> childList; /* 存储子目录或文件 */
28 public :
29 Folder( string name) { this -> name = name;}
30 void addChild(AbstractFile * file) {childList.push_back(file);}
31 void removeChild(AbstractFile * file) {childList.remove(file);}
32 list < AbstractFile *> * getChildren() { return & childList;}
33 };
34
35 int main() {
36 AbstractFile * rootFolder = new Folder( " c:\\ " );
37 AbstractFile * compositeFolder = new Folder( " composite " );
38 AbstractFile * WindowsFolder = new Folder( " Windows " );
39 AbstractFile * file = new File( " TestComposite.C++ " );
40 rootFolder -> addChild(compositeFolder);
41 rootFolder -> addChild(WindowsFolder);
42 compositeFolder -> addChild(file);
43 rootFolder -> printName();
44 compositeFolder -> printName();
45 WindowsFolder -> printName();
46 file -> printName();
47 return 0 ;
48 }