From 97bdec1f62fd80ea79e11c8d7c7e42c060c4c543 Mon Sep 17 00:00:00 2001
From: zcy <290198252@qq.com>
Date: Sun, 24 Apr 2022 01:33:12 +0800
Subject: [PATCH] add AOP pattern

---
 general/src/pattern/aspect.hpp             |  72 +++++++++++
 test/src/test_cpu_usage/test_cpu_usage.cpp | 144 +++++++++++++++++++++
 2 files changed, 216 insertions(+)
 create mode 100644 general/src/pattern/aspect.hpp

diff --git a/general/src/pattern/aspect.hpp b/general/src/pattern/aspect.hpp
new file mode 100644
index 0000000..b2fcaaf
--- /dev/null
+++ b/general/src/pattern/aspect.hpp
@@ -0,0 +1,72 @@
+#include <iostream>
+
+
+#define HAS_MEMBER(member) \
+template<typename T, typename ...Args> \
+struct has_member_##member \
+{	\
+private: \
+template<typename U> \
+static auto check(int) -> decltype(std::declval<U>().member(std::declval<Args>()...), std::true_type()); \
+template<typename U> \
+static std::false_type check(...); \
+public: \
+enum {value = std::is_same<decltype(check<T>(0)), std::true_type>::value}; \
+}; \
+
+
+template<typename Func, typename...Args>
+struct Aspect
+{
+	//forward or move 是一样的
+	Aspect(Func&& f) : m_func(std::forward<Func>(f)) {}
+
+	template<typename T>
+	typename std::enable_if<has_member_before<T, Args...>::value
+	&& has_member_after<T, Args...>::value>::type
+		invoke(Args&&...args, T&& aspect)
+	{
+		aspect.before(std::forward<Args>(args)...);	//切面逻辑
+		m_func(std::forward<Args>(args)...);		//核心逻辑
+		aspect.after(std::forward<Args>(args)...);	//切面逻辑
+	}
+
+	template<typename T>
+	typename std::enable_if<has_member_before<T, Args...>::value
+		&& !has_member_after<T, Args...>::value>::type
+		invoke(Args&&...args, T&& aspect)
+	{
+		aspect.before(std::forward<Args>(args)...);	//切面逻辑
+		m_func(std::forward<Args>(args)...);		//核心逻辑
+	}
+
+	template<typename T>
+	typename std::enable_if<!has_member_before<T, Args...>::value
+		&& has_member_after<T, Args...>::value>::type
+		invoke(Args&&...args, T&& aspect)
+	{
+		m_func(std::forward<Args>(args)...);		//核心逻辑
+		aspect.after(std::forward<Args>(args)...);	//切面逻辑
+	}
+
+	//适应切片组合
+	template<typename Head, typename...Tail>
+	void invoke(Args&&...args, Head&& headAspect, Tail&&...tailAspect)
+	{
+		headAspect.before(std::forward<Args>(args)...);	//切面逻辑
+		invoke(std::forward<Args>(args)..., std::forward<Tail>(tailAspect)...);
+		headAspect.after(std::forward<Args>(args)...);	//切面逻辑
+	}
+
+private:
+	Func		m_func;	//最终核心逻辑
+};
+
+//辅助调用函数
+template<typename...Ap, typename...Args, typename Func>
+void invoke(Func&& f, Args&&...args)
+{
+	Aspect<Func, Args...> asp(std::forward<Func>(f));
+	asp.invoke(std::forward<Args>(args)..., Ap()...);
+}
+
diff --git a/test/src/test_cpu_usage/test_cpu_usage.cpp b/test/src/test_cpu_usage/test_cpu_usage.cpp
index 0bf14cc..aa67c77 100644
--- a/test/src/test_cpu_usage/test_cpu_usage.cpp
+++ b/test/src/test_cpu_usage/test_cpu_usage.cpp
@@ -5,6 +5,150 @@
 #include <stdio.h>
 using namespace std;
 
+#define HAS_MEMBER(member) \
+template<typename T, typename ...Args> \
+struct has_member_##member \
+{	\
+private: \
+template<typename U> \
+static auto check(int) -> decltype(std::declval<U>().member(std::declval<Args>()...), std::true_type()); \
+template<typename U> \
+static std::false_type check(...); \
+public: \
+enum {value = std::is_same<decltype(check<T>(0)), std::true_type>::value}; \
+}; \
+
+
+HAS_MEMBER(before)
+HAS_MEMBER(after)
+
+template<typename Func, typename...Args>
+struct Aspect
+{
+	//forward or move 是一样的
+	Aspect(Func&& f) : m_func(std::forward<Func>(f)) {}
+
+	template<typename T>
+	typename std::enable_if<has_member_before<T, Args...>::value
+	&& has_member_after<T, Args...>::value>::type
+		invoke(Args&&...args, T&& aspect)
+	{
+		aspect.before(std::forward<Args>(args)...);	//切面逻辑
+		m_func(std::forward<Args>(args)...);		//核心逻辑
+		aspect.after(std::forward<Args>(args)...);	//切面逻辑
+	}
+
+	template<typename T>
+	typename std::enable_if<has_member_before<T, Args...>::value
+		&& !has_member_after<T, Args...>::value>::type
+		invoke(Args&&...args, T&& aspect)
+	{
+		aspect.before(std::forward<Args>(args)...);	//切面逻辑
+		m_func(std::forward<Args>(args)...);		//核心逻辑
+	}
+
+	template<typename T>
+	typename std::enable_if<!has_member_before<T, Args...>::value
+		&& has_member_after<T, Args...>::value>::type
+		invoke(Args&&...args, T&& aspect)
+	{
+		m_func(std::forward<Args>(args)...);		//核心逻辑
+		aspect.after(std::forward<Args>(args)...);	//切面逻辑
+	}
+
+	//适应切片组合
+	template<typename Head, typename...Tail>
+	void invoke(Args&&...args, Head&& headAspect, Tail&&...tailAspect)
+	{
+		headAspect.before(std::forward<Args>(args)...);	//切面逻辑
+		invoke(std::forward<Args>(args)..., std::forward<Tail>(tailAspect)...);
+		headAspect.after(std::forward<Args>(args)...);	//切面逻辑
+	}
+
+private:
+	Func		m_func;	//最终核心逻辑
+};
+
+//辅助调用函数
+template<typename...Ap, typename...Args, typename Func>
+void invoke(Func&& f, Args&&...args)
+{
+	Aspect<Func, Args...> asp(std::forward<Func>(f));
+	asp.invoke(std::forward<Args>(args)..., Ap()...);
+}
+
+struct AA
+{
+	void before(int i)
+	{
+		cout << "before AA:" << i << endl;
+	}
+	void after(int i)
+	{
+		cout << "after AA:" << i << endl;
+	}
+};
+
+struct CC
+{
+	void before(int i)
+	{
+		cout << "before CC:" << i << endl;
+	}
+	void after(int i)
+	{
+		cout << "after CC:" << i << endl;
+	}
+};
+
+struct BB
+{
+	void before()
+	{
+		cout << "before BB" << endl;
+	}
+	void after()
+	{
+		cout << "after BB" << endl;
+	}
+};
+
+struct DD
+{
+	void before()
+	{
+		cout << "before DD" << endl;
+	}
+	void after()
+	{
+		cout << "after DD" << endl;
+	}
+};
+
+void gt()
+{
+	cout << "gt functional" << endl;
+}
+
+void ht(int i)
+{
+	cout << "ht functional:" << i << endl;
+}
+
+void test()
+{
+	//织入普通函数
+	std::function<void(int)> f = std::bind(&ht, std::placeholders::_1);
+	invoke<AA, CC>(f, 1);
+
+	cout << "------------------------" << endl;
+	//织入普通函数
+	invoke<BB, DD>(&gt);
+	cout << "------------------------" << endl;
+	invoke<CC, AA>(&ht, 1);
+}
+
+
 int main(int argc, char **argv)
 {
     CProcessMonitor usage1(26644);