template

Template Method/Makefile

+all:
+	g++ -g -Wall -o template1 template1_lib.cpp template1_app.cpp
+	g++ -g -Wall -o template2 template2_lib.cpp template2_app.cpp
+
+clean:
+	rm -rf template1 template2
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Template Method/template1_app.cpp

+#include "template1_lib.cpp"
+
+//Ӧó򿪷Ա
+class Application
+{
+  public:
+	bool Step2()
+	{
+		cout << "myStep2" << endl;
+		return true;
+	}
+
+	void Step4()
+	{
+		cout << "myStep4" << endl;
+	}
+};
+
+int main()
+{
+	Library lib;
+	Application app;
+
+	lib.Step1();
+
+	if (app.Step2())
+	{
+		lib.Step3();
+	}
+
+	for (int i = 0; i < 4; i++)
+	{
+		app.Step4();
+	}
+
+	lib.Step5();
+}

Template Method/template1_lib.cpp

+#include <iostream>
+
+using namespace std;
+
+//³ÌÐò¿â¿ª·¢ÈËÔ±
+class Library
+{
+
+public:
+	void Step1()
+	{
+		cout << "Step1" << endl;
+	}
+
+	void Step3()
+	{
+		cout << "Step3" << endl;
+	}
+
+	void Step5()
+	{
+		cout << "Step5" << endl;
+	}
+};
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Template Method/template2_app.cpp

+#include "template2_lib.cpp"
+#include <iostream>
+
+using namespace std;
+
+//应用程序开发人员
+class Application : public Library
+{
+  protected:
+	virtual bool Step2()
+	{
+		//... 子类重写实现
+		cout << "override Step2" << endl;
+		return true;
+	}
+
+	virtual void Step4()
+	{
+		//... 子类重写实现
+		cout << "override Step4" << endl;
+	}
+};
+
+int main()
+{
+	Library *pLib = new Application();
+	pLib->Run();
+
+	delete pLib;
+}

Template Method/template2_lib.cpp

+#include <iostream>
+
+using namespace std;
+
+//程序库开发人员
+class Library
+{
+  public:
+    //稳定 template method
+    void Run()
+    {
+        Step1();
+
+        if (Step2())
+        { //支持变化 ==> 虚函数的多态调用
+            Step3();
+        }
+
+        for (int i = 0; i < 4; i++)
+        {
+            Step4(); //支持变化 ==> 虚函数的多态调用
+        }
+
+        Step5();
+    }
+    virtual ~Library() {}
+
+  protected:
+    void Step1()
+    { //稳定
+        cout << "Step1" << endl;
+    }
+    void Step3()
+    { //稳定
+        cout << "Step3" << endl;
+    }
+    void Step5()
+    {   //稳定
+        cout << "Step5" << endl;
+    }
+
+    virtual bool Step2() = 0; //变化
+    virtual void Step4() = 0; //变化
+};
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