设计模式之职责链模式

题目

某物资管理系统中物资采购需要分级审批，主任可以审批1万元及以下的采购单，部门经理可以审批5万元及以下的采购单，副总经理可以审批10万元及以下的采购单，总经理可以审批20万元及以下的采购单，20万元以上的采购单需要开职工大会确定。现用职责链模式设计该系统。

类图

Java

Approver抽象类

package com.gazikel;

public abstract class Approver {

    // 下一个后继者
    Approver approver;
    // 职位
    String position;

    public Approver(String position) {
        this.position = position;
    }

    // 下一个处理者

    public void setApprover(Approver approver) {
        this.approver = approver;
    }

    // 处理审批请求的方法
    public abstract void processRequest(PurchaseRequest purchaseRequest);
}

Approver抽象类

DepartmentManager

package com.gazikel;

public class DepartmentManager extends Approver {

    public DepartmentManager(String name) {
        super(name);
    }

    @Override
    public void processRequest(PurchaseRequest purchaseRequest) {
        if (purchaseRequest.getPrice() > 10000 && purchaseRequest.getPrice() <= 50000) {
            System.out.println("请求编号id => " + purchaseRequest.getId() + "被" + this.position + "处理");
        } else {
            approver.processRequest(purchaseRequest);
        }

    }
}

Director

package com.gazikel;

public class Director extends Approver {

    public Director(String name) {
        super(name);
    }

    @Override
    public void setApprover(Approver approver) {
        super.setApprover(approver);
    }

    @Override
    public void processRequest(PurchaseRequest purchaseRequest) {
        if (purchaseRequest.getPrice() <= 10000) {
            System.out.println("请求编号id => " + purchaseRequest.getId() + "被" + this.position + "处理");
        } else {
            approver.processRequest(purchaseRequest);
        }

    }
}

GeneralManager

package com.gazikel;

public class GeneralManager extends Approver {

    public GeneralManager(String name) {
        super(name);
    }


    @Override
    public void processRequest(PurchaseRequest purchaseRequest) {
        if (purchaseRequest.getPrice() > 100000 && purchaseRequest.getPrice() <= 200000) {
            System.out.println("请求编号id => " + purchaseRequest.getId() + "被" + this.position + "处理");
        } else {
            System.out.println("需要开员工大会确定");
        }

    }
}

ViceManager

package com.gazikel;

public class ViceManager extends Approver {

    public ViceManager(String name) {
        super(name);
    }

    @Override
    public void processRequest(PurchaseRequest purchaseRequest) {
        if (purchaseRequest.getPrice() > 50000 && purchaseRequest.getPrice() <= 100000) {
            System.out.println("请求编号id => " + purchaseRequest.getId() + "被" + this.position + "处理");
        } else {
            approver.processRequest(purchaseRequest);
        }

    }
}

PurchaseRequest

package com.gazikel;

public class PurchaseRequest {

    private int type;
    private float price;
    private int id;

    public PurchaseRequest(int type, float price, int id) {
        this.type = type;
        this.price = price;
        this.id = id;
    }

    public int getType() {
        return type;
    }

    @Override
    public String toString() {
        return this.getId() + "号物资" + this.getPrice() + "元";
    }

    public float getPrice() {
        return price;
    }

    public int getId() {
        return id;
    }
}

Client

package com.gazikel;

public class Client {

    public static void main(String[] args) {
        PurchaseRequest purchaseRequest1 = new PurchaseRequest(1, 5600, 1);
        PurchaseRequest purchaseRequest2 = new PurchaseRequest(1, 25620, 2);
        PurchaseRequest purchaseRequest3 = new PurchaseRequest(1, 96541, 3);
        PurchaseRequest purchaseRequest4 = new PurchaseRequest(1, 152345, 4);
        PurchaseRequest purchaseRequest5 = new PurchaseRequest(1, 235685, 5);


        Director director = new Director("主任");
        DepartmentManager departmentManager = new DepartmentManager("部门经理");
        ViceManager viceManager = new ViceManager("副总经理");
        GeneralManager generalManager = new GeneralManager("总经理");

        director.setApprover(departmentManager);
        departmentManager.setApprover(viceManager);
        viceManager.setApprover(generalManager);

        System.out.println(purchaseRequest1.toString());
        director.processRequest(purchaseRequest1);
        System.out.println("-------------------------------");

        System.out.println(purchaseRequest2.toString());
        director.processRequest(purchaseRequest2);
        System.out.println("-------------------------------");

        System.out.println(purchaseRequest3.toString());
        director.processRequest(purchaseRequest3);
        System.out.println("-------------------------------");

        System.out.println(purchaseRequest4.toString());
        director.processRequest(purchaseRequest4);
        System.out.println("-------------------------------");

        System.out.println(purchaseRequest5.toString());
        director.processRequest(purchaseRequest5);
        System.out.println("-------------------------------");

    }

}

C++

#include<iostream>
#include<string>
using namespace std;

class PurchaseRequest {
private:
	int type;
	float price;
	int id;

public:
	PurchaseRequest(int type, float price, int id) {
		this->type = type;
		this->price = price;
		this->id = id;
	}

	float GetPrice() {
		return this->price;
	}

	int GetId() {
		return this->id;
	}

	void Print() {
		cout << this->GetId() << "号物资" << this->GetPrice() << "元";
	}
};

class Approver {
protected:
	Approver* approver;
	string position;

public:
	Approver(string position) {
		this->position = position;
	}

	void SetApprover(Approver* approver) {
		this->approver = approver;
	}

	virtual void ProcessRequest(PurchaseRequest* purchaseRequest) = 0;
};

class Director :public Approver {
public:
	Director(string position) :Approver(position) {}

	void SetApprover(Approver *approver) {
		this->approver = approver;
	}

	void ProcessRequest(PurchaseRequest* purchaseRequest) {
		if (purchaseRequest->GetPrice() <= 10000.0)
		{
			cout << "请求编号id =>" << purchaseRequest->GetId() << "被" << this->position << "处理了" << endl;
		}
		else {
			approver->ProcessRequest(purchaseRequest);
		}
	}
};

class DepartmentManager :public Approver {
public:
	DepartmentManager(string position) :Approver(position) {}

	void SetApprover(Approver* approver) {
		this->approver = approver;
	}

	void ProcessRequest(PurchaseRequest* purchaseRequest) {
		if (purchaseRequest->GetPrice() > 10000.0 && purchaseRequest->GetPrice() <= 50000.0) {
			cout << "请求编号id =>" << purchaseRequest->GetId() << "被" << this->position << "处理了" << endl;

		}
		else {
			approver->ProcessRequest(purchaseRequest);
		}
	}
};

class ViceManager :public Approver {
public:
	ViceManager(string position) :Approver(position) {}

	void SetApprover(Approver* approver) {
		this->approver = approver;
	}

	void ProcessRequest(PurchaseRequest* purchaseRequest) {
		if (purchaseRequest->GetPrice() > 50000.0 && purchaseRequest->GetPrice() <= 100000.0) {
			cout << "请求编号id =>" << purchaseRequest->GetId() << "被" << this->position << "处理了" << endl;
		}
		else {
			approver->ProcessRequest(purchaseRequest);
		}
	}
};

class GeneralManager :public Approver {
public:
	GeneralManager(string position) :Approver(position) {}

	void SetApprover(Approver* approver) {
		this->approver = approver;
	}

	void ProcessRequest(PurchaseRequest* purchaseRequest) {
		if (purchaseRequest->GetPrice() > 100000.0 && purchaseRequest->GetPrice() <= 200000.0) {
			cout << "请求编号id =>" << purchaseRequest->GetId() << "被" << this->position << "处理了" << endl;

		}
		else {
			cout << "需要开员工大会决定" << endl;
		}
	}
};

int main() {
	PurchaseRequest* purchaseRequest1 = new PurchaseRequest(1, 5600, 1);
	PurchaseRequest* purchaseRequest2 = new PurchaseRequest(1, 25620, 2);
	PurchaseRequest* purchaseRequest3 = new PurchaseRequest(1, 96541, 3);
	PurchaseRequest* purchaseRequest4 = new PurchaseRequest(1, 152345, 4);
	PurchaseRequest* purchaseRequest5 = new PurchaseRequest(1, 235685, 5);

	Director* director = new Director("主任");
	DepartmentManager* departmentManager = new DepartmentManager("部门经理");
	ViceManager* viceManager = new ViceManager("副总经理");
	GeneralManager* generalManager = new GeneralManager("总经理");

	director->SetApprover(departmentManager);
	departmentManager->SetApprover(viceManager);
	viceManager->SetApprover(generalManager);

	cout << purchaseRequest1->GetId() << "金额" << purchaseRequest1->GetPrice() << endl;
	director->ProcessRequest(purchaseRequest1);
	cout << "---------------------------------------" << endl;

	cout << purchaseRequest2->GetId() << "金额" << purchaseRequest2->GetPrice() << endl;
	director->ProcessRequest(purchaseRequest2);
	cout << "---------------------------------------" << endl;
	
	cout << purchaseRequest3->GetId() << "金额" << purchaseRequest3->GetPrice() << endl;
	director->ProcessRequest(purchaseRequest3);
	cout << "---------------------------------------" << endl;

	cout << purchaseRequest4->GetId() << "金额" << purchaseRequest4->GetPrice() << endl;
	director->ProcessRequest(purchaseRequest4);
	cout << "---------------------------------------" << endl;

	cout << purchaseRequest5->GetId() << "金额" << purchaseRequest5->GetPrice() << endl;
	director->ProcessRequest(purchaseRequest5);
	cout << "---------------------------------------" << endl;
}