2024/11/16

实验15：职责链模式
本次实验属于模仿型实验，通过本次实验学生将掌握以下内容：
1、理解职责链模式的动机，掌握该模式的结构；
2、能够利用职责链模式解决实际问题。

[实验任务一]：财务审批
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。
实验要求：
1. 提交类图；

2. 提交源代码；
public abstract class Leader
{
protected String name;
protected Leader successor;

public Leader(String name)
{
this.name = name;
}

public void setSuccessor(Leader successor)
{
this.successor = successor;
}

public abstract void handleRequest(PurchaseRequest request);
}

public class DepartmentManager extends Leader
{
public DepartmentManager(String name)
{
super(name);
}

@Override
public void handleRequest(PurchaseRequest request)
{
if (request.getMoney() <= 50000)
{
System.out.println("部门经理" + name + "审批采购单，采购单单号为：" + request.getId() + ",金额为：" + request.getMoney() + "元");
} else
{
if (this.successor != null)
{
this.successor.handleRequest(request);
}
}
}
}

public class Director extends Leader
{
public Director(String name)
{
super(name);
}

@Override
public void handleRequest(PurchaseRequest request)
{
if (request.getMoney() <= 10000)
{
System.out.println("主任" + name + "审批采购单，采购单单号为：" + request.getId() + ",金额为：" + request.getMoney() + "元");
} else
{
if (this.successor != null)
{
this.successor.handleRequest(request);
}
}
}
}

public class GeneralManager extends Leader
{
public GeneralManager(String name)
{
super(name);
}

@Override
public void handleRequest(PurchaseRequest request)
{
if (request.getMoney() <= 200000)
{
System.out.println("总经理" + name + "审批采购单，采购单单号为：" + request.getId() + ",金额为：" + request.getMoney() + "元");
} else
{
System.out.println("采购单单号为：" + request.getId() + ",金额为：" +request.getMoney() + "元，金额太大，需开职工大会确定是否审批通过");
}
}
}

public class Manager extends Leader
{

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

@Override
public void handleRequest(PurchaseRequest request)
{
if (request.getMoney() <= 100000)
{
System.out.println("副总经理" + name + "审批采购单，采购单单号为：" + request.getId() + ",金额为：" + request.getMoney() + "元");
} else
{
if (this.successor != null)
{
this.successor.handleRequest(request);
}
}
}
}

public class PurchaseRequest
{
private int money;
private int id;

public PurchaseRequest(int id, int money)
{
this.id = id;
this.money = money;
}

public int getMoney()
{
return money;
}

public void setMoney(int money)
{
this.money = money;
}

public int getId()
{
return id;
}

public void setId(int id)
{
this.id = id;
}
}

public class Client
{
public static void main(String[] args)
{
Leader objDirector, objDepartmentManager, objManager, objGeneralManager;

objDirector = new Director("张三");
objDepartmentManager = new DepartmentManager("李四");
objManager = new Manager("王五");
objGeneralManager = new GeneralManager("赵六");

objDirector.setSuccessor(objDepartmentManager);
objDepartmentManager.setSuccessor(objManager);
objManager.setSuccessor(objGeneralManager);

PurchaseRequest pr1=new PurchaseRequest(1001,10000);
objDirector.handleRequest(pr1);

PurchaseRequest pr2=new PurchaseRequest(1002,50000);
objDirector.handleRequest(pr2);

PurchaseRequest pr3=new PurchaseRequest(1003,100000);
objDirector.handleRequest(pr3);

PurchaseRequest pr4=new PurchaseRequest(1004,200000);
objDirector.handleRequest(pr4);

PurchaseRequest pr5=new PurchaseRequest(1005,200001);
objDirector.handleRequest(pr5);
}
}
3. 注意编程规范。