C++的组合(Composite)模式

现欲构造一个文件/目录树，采用组合(Composite)设计模式来设计，得到的类图如下：

C++代码为：

#include <list>
#include <iostream>
#include <string>

 using namespace std;

 class AbstractFile {
protected:
    string name;   /*文件或目录名*/
public:
    void printName() {cout<<name<<endl;}    /*打印文件或目录名称*/
    virtual void addChild(AbstractFile *file)=0;  /*给一个目录增加子目录或文件*/
    virtual void removeChild(AbstractFile *file)=0;  /*删除一个目录的子目录或文件*/
    virtual list<AbstractFile *> *getChildren()=0;   /*保存一个目录的子目录或文件*/
};

class File:public AbstractFile{
public:
    File(string name) {this->name=name;}
    void addChild(AbstractFile *file) {return;}
    void removeChild(AbstractFile *file) {return;}
    list<AbstractFile *> *getChildren() {return NULL;}
};

class Folder:public AbstractFile {
private:
    list<AbstractFile *> childList;   /*存储子目录或文件*/
public:
    Folder(string name) {this->name=name;}
    void addChild(AbstractFile *file) {childList.push_back(file);}
    void removeChild(AbstractFile *file) {childList.remove(file);}
    list<AbstractFile *> *getChildren() {return &childList;}
};

int main() {
    AbstractFile *rootFolder=new Folder("c:\\");
    AbstractFile *compositeFolder=new Folder("composite");
    AbstractFile *WindowsFolder=new Folder("Windows");
    AbstractFile *file=new File("TestComposite.C++");
    rootFolder->addChild(compositeFolder);
    rootFolder->addChild(WindowsFolder);
    compositeFolder->addChild(file);
    rootFolder->printName();
    compositeFolder->printName();
    WindowsFolder->printName();
    file->printName();
    return 0;
}