设计模式go语言实现----职责链模式ChainOfResponsibility

本文链接：https://blog.youkuaiyun.com/cloudUncle/article/details/84865967

本文深入解析职责链设计模式，通过具体实例展示如何在Go语言中实现这一模式，以解决请求处理过程中不同对象间的耦合问题。文章通过请假和加薪审批流程的场景，详细说明了职责链模式的工作原理。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

1 定义

职责链模式(Chain Of Responsibility)：使多个对象都有机会处理请求，从而避免请求的发送者和接收者之间的耦合关系。将这个对象连成一条链，并沿着这条链传递该请求，直到有一个对象处理它为止。

现实生活中有很多类似职责链模式的例子，比如我们在公司请假需要填写电子流给各个领导审批，如果请假时长比较短的时候，你的直属领导就有权力决定是否同意你请假，但是如果时间比较长的话，那就要给更高一层的领导审批了，类似的还有加薪申请也是一样的情况。
其UML类图如下：

UML类图：
在这里插入图片描述

2 golang实现

2.1 实现各角色

package chainofresponsibility

import "fmt"

type Request struct {
	RequestType    string
	RequestContent string
	Number         int
}

type Manager interface {
	SetNext(next Manager)
	RequestHandler(request Request)
}

type CommonManager struct {
	Manager
	Name string
}

func (cm *CommonManager) SetNext(next Manager) {
	cm.Manager = next
}

func (cm *CommonManager) RequestHandler(request Request) {
	if request.RequestType == "请假" && request.Number <= 2 {
		fmt.Printf("%s: %s 数量 %d 已批准\n", cm.Name, request.RequestContent, request.Number)
	} else {
		if cm.Manager != nil {
			cm.Manager.RequestHandler(request)
		}
	}
}

type MajorManager struct {
	Manager
	Name string
}

func (mm *MajorManager) SetNext(next Manager) {
	mm.Manager = next
}

func (mm *MajorManager) RequestHandler(request Request) {
	if request.RequestType == "请假" && request.Number <= 5 {
		fmt.Printf("%s: %s 数量 %d 已批准\n", mm.Name, request.RequestContent, request.Number)
	} else {
		if mm.Manager != nil {
			mm.Manager.RequestHandler(request)
		}
	}
}

type GeneralManager struct {
	Manager
	Name string
}

func (gm *GeneralManager) SetNext(next Manager) {
	gm.Manager = next
}

func (gm *GeneralManager) RequestHandler(request Request) {
	if request.RequestType == "请假" {
		fmt.Printf("%s: %s 数量 %d 已批准\n", gm.Name, request.RequestContent, request.Number)
	} else if request.RequestType == "加薪" && request.Number <= 500 {
		fmt.Printf("%s: %s 数量 %d 已批准\n", gm.Name, request.RequestContent, request.Number)
	} else if request.RequestType == "加薪" && request.Number > 500 {
		fmt.Printf("%s: %s 数量 %d 再说吧\n", gm.Name, request.RequestContent, request.Number)
	}
}

2.2 客户端调用

func main() {
	wenxiang := &chainofresponsibility.CommonManager{
		Name: "文祥",
	}
	xiaoyun := &chainofresponsibility.MajorManager{
		Name: "晓云",
	}
	yuanlei := &chainofresponsibility.GeneralManager{
		Name: "苑磊",
	}
	wenxiang.SetNext(xiaoyun)
	xiaoyun.SetNext(yuanlei)

	request := chainofresponsibility.Request{
		RequestType:    "请假",
		RequestContent: "小菜请假",
		Number:         2,
	}
	wenxiang.RequestHandler(request)

	request = chainofresponsibility.Request{
		RequestType:    "请假",
		RequestContent: "小菜请假",
		Number:         5,
	}
	wenxiang.RequestHandler(request)

	request = chainofresponsibility.Request{
		RequestType:    "加薪",
		RequestContent: "小菜请求加薪",
		Number:         500,
	}
	wenxiang.RequestHandler(request)

	request = chainofresponsibility.Request{
		RequestType:    "加薪",
		RequestContent: "小菜请求加薪",
		Number:         1000,
	}
	wenxiang.RequestHandler(request)
}