标签：set uml rri alt leave enc 解耦 tle bsp
一，概念：
责任链模式（Chain of Responsibility Pattern）为请求创建了一个接收者对象的链。这种模式给予请求的类型，对请求的发送者和接收者进行解耦。这种类型的设计模式属于行为型模式。在这种模式中，通常每个接收者都包含对另一个接收者的引用。如果一个对象不能处理该请求，那么它会把相同的请求传给下一个接收者，依此类推。
主要解决职责链上的处理者负责处理请求，客户只需要将请求发送到职责链上即可，无须关心请求的处理细节和请求的传递，所以职责链将请求的发送者和请求的处理者解耦了。
二，UML图：
Handler定义一个处理请示的接口；
ConcreteHandler具体处理者类，处理它所负责的请求，可访问它的后继者，如果可以处理该请求，就处理，否则就将该请求转发给它的后继者。
Handler 里面聚合它自己，在 HandlerRequest 里判断是否合适，如果没达到条件则向下传递，向谁传递之前 set 进去。
最重要的两点，一个是你需要事先给每个具体管理者设置它的上司是哪个类，也就是设置后继者。另一点就是你需要在每个具体管理者处理请求时，做出判断，是可以处理这个请求，还是必须要“推卸责任”，转移给后继者去处理。
三，使用场景：
1、有多个对象可以处理同一个请求，具体哪个对象处理该请求由运行时刻自动确定。
2、在不明确指定接收者的情况下，向多个对象中的一个提交一个请求。
3、可动态指定一组对象处理请求。
四，代码实例：
struct Leaving {
var title: String
var reasone: String
var from: String
var position: String
var leaveDaysNum: Float
}
protocol Leader {
var superior: Leader? {get set}
var leaderPosition: String {get set}
var controlLeavingDataTimeMix: Float {get set}
var controlLeavingDataTimeMax: Float {get set}
func handleLeaving(leaving: Leaving) -> Bool;
}
class CommonLeader: Leader {
var superior: Leader?
var leaderPosition: String
var controlLeavingDataTimeMix: Float
var controlLeavingDataTimeMax: Float
init(superior: Leader?, position: String, mixTime: Float, maxTime: Float) {
self.superior = superior
leaderPosition = position
controlLeavingDataTimeMax = maxTime
controlLeavingDataTimeMix = mixTime
}
}
extension Leader{
func handleLeaving(leaving: Leaving) -> Bool {
if leaving.leaveDaysNum >= controlLeavingDataTimeMix, leaving.leaveDaysNum <= controlLeavingDataTimeMax {
print("I‘m \(leaderPosition), I agree!")
return true
}else if leaving.leaveDaysNum > controlLeavingDataTimeMax{
if let superboss = superior{
print("I‘m \(leaderPosition), Your leave longer than my control,i should ask my superior!")
return superboss.handleLeaving(leaving: leaving)
}else{
print("I‘m \(leaderPosition), Your leave time is too long, I‘m against it")
return false;
}
}else{
print("I‘m \(leaderPosition), you have a problem with leaving time thus can‘t agree with you.")
return false
}
}
}
class TeamLeader: CommonLeader {
init(superior: Leader?) {
super.init(superior: superior, position: "Team Leader", mixTime: 0.5, maxTime: 1.0)
}
}
class DepartmentHead: CommonLeader {
init(superior: Leader?) {
super.init(superior: superior, position: "Department Head", mixTime: 1.5, maxTime: 7.0)
}
}
class CompanyManager: CommonLeader {
init(superior: Leader?) {
super.init(superior: superior, position: "Company Manager", mixTime: 7.5, maxTime: 31.0)
}
}
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
let leaving = Leaving(title: "I‘d like to have paternity leave.", reasone: "My wife would have a baby in recent days.", from: "Ternence", position: "iOS engineer", leaveDaysNum: 15.0)
let CM = CompanyManager(superior: nil)
let DH = DepartmentHead(superior: CM)
let TL = TeamLeader(superior: DH)
print(TL.handleLeaving(leaving: leaving))
}
}
标签：set uml rri alt leave enc 解耦 tle bsp
原文地址：https://www.cnblogs.com/yangzigege/p/8969883.html
