53 lines
866 B
C
53 lines
866 B
C
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#include <string>
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#include <iostream>
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using namespace std;
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class Image
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{
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public:
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Image(){}
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virtual ~Image(){}
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virtual void display() = 0;
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};
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class RealImage : public Image
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{
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public:
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RealImage(string fileName) : fileName(fileName)
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{
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loadFromDisk(fileName);
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}
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void loadFromDisk(string fileName)
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{
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cout << "Loading " + fileName << endl;
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}
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void display()
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{
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cout << "Displaying " + fileName << endl;
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}
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private:
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string fileName;
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};
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class ProxyImage : public Image
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{
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public:
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ProxyImage(string fileName) : fileName(fileName)
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{
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realImage = nullptr;
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}
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void display()
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{
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if (realImage == nullptr)
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{
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realImage = new RealImage(fileName);
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}
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realImage->display();
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}
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private:
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RealImage *realImage;
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string fileName;
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};
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