设计模式DP-责任链模式

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

// 定义业务处理者抽象类
typedef struct Handler {
	struct Handler* nextHandler;
	void (*handleRequest)(struct Handler* handler, int request);
	void (*setNextHandler)(struct Handler* CurHandler, struct Handler* NextHandler);
} Handler;
void setNextHandler(struct Handler* CurHandler, struct Handler* NextHandler)
{
	if (!CurHandler) {
		printf("handler is null\n");
	return;
	}
	CurHandler->nextHandler = NextHandler;
}

// 业务处理者子类1
typedef struct ConcreteHandler1 {
	Handler handler;
} ConcreteHandler1;
void ConcreteHandler1_handleRequest(Handler* handler, int request) {
	if (request >= 0 && request < 10) {
		printf("ConcreteHandler1 处理请求 %d\n", request);
	} else if (handler->nextHandler != NULL) {
		// 转发给下一个处理者
		handler->nextHandler->handleRequest(handler->nextHandler, request);
	} else {
		printf("无法处理请求 %d\n", request);
	}
}

// 业务处理者子类2
typedef struct ConcreteHandler2 {
	Handler handler;
} ConcreteHandler2;
void ConcreteHandler2_handleRequest(Handler* handler, int request) {
	if (request >= 10 && request < 20) {
	    printf("ConcreteHandler2 处理请求 %d\n", request);
	} else if (handler->nextHandler != NULL) {
	    // 转发给下一个处理者
	    handler->nextHandler->handleRequest(handler->nextHandler, request);
	} else {
	    printf("无法处理请求 %d\n", request);
	}
}

int main(int argc, char *argv[])
{
	// 创建业务处理者对象
	ConcreteHandler1* handler1 = (ConcreteHandler1*)malloc(sizeof(ConcreteHandler1));
	ConcreteHandler2* handler2 = (ConcreteHandler2*)malloc(sizeof(ConcreteHandler2));
	// 设置责任链关系
	handler1->handler.handleRequest = ConcreteHandler1_handleRequest;
	handler1->handler.setNextHandler = setNextHandler;
	handler1->handler.setNextHandler(&handler1->handler, &handler2->handler);
	
	handler2->handler.handleRequest = ConcreteHandler2_handleRequest;
	handler1->handler.setNextHandler = setNextHandler;
	handler1->handler.setNextHandler(&handler2->handler, NULL);
		
	// 模拟客户端发送请求
	int requests[] = {5, 12, 18, 25};
	int i;
	for (i = 0; i < sizeof(requests) / sizeof(int); i++) {
		handler1->handler.handleRequest((Handler*)handler1, requests[i]);
	}

	// 释放内存
	free(handler1);
	free(handler2);
	return 0;
}

• ()[https://zhuanlan.zhihu.com/p/670001095]
• ()[https://blog.csdn.net/feixiaoxing/article/details/7085567]
• ()[https://blog.csdn.net/jenie/article/details/106484892]