软件设计-Tutorial15

```mermaid
classDiagram
    Approver <|-- Director
    Approver <|-- DepartmentManager
    Approver <|-- VicePresident
    Approver <|-- President
    Approver <|-- StaffMeeting
    Approver --> Approver : nextApprover

    class Approver {
        -Approver nextApprover
        -String name
        +setNextApprover(Approver)
        +approveRequest(PurchaseRequest)
    }

    class Director {
        +approveRequest(PurchaseRequest)
    }

    class DepartmentManager {
        +approveRequest(PurchaseRequest)
    }

    class VicePresident {
        +approveRequest(PurchaseRequest)
    }

    class President {
        +approveRequest(PurchaseRequest)
    }

    class StaffMeeting {
        +approveRequest(PurchaseRequest)
    }

    class PurchaseRequest {
        -double amount
        -String purpose
        +getAmount()
        +getPurpose()
    }

    Approver o-- PurchaseRequest : uses

```

// 抽象类：定义一个抽象的审批者
abstract class Approver {
    protected Approver nextApprover; // 下一个审批者
    protected String name; // 审批者的名称

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

    // 设置下一个审批者
    public void setNextApprover(Approver nextApprover) {
        this.nextApprover = nextApprover;
    }

    // 抽象方法：处理采购请求
    public abstract void approveRequest(PurchaseRequest request);
}

// 采购请求类
class PurchaseRequest {
    private double amount; // 采购金额
    private String purpose; // 采购目的

    public PurchaseRequest(double amount, String purpose) {
        this.amount = amount;
        this.purpose = purpose;
    }

    public double getAmount() {
        return amount;
    }

    public String getPurpose() {
        return purpose;
    }
}

// 主任审批类
class Director extends Approver {
    public Director(String name) {
        super(name);
    }

    @Override
    public void approveRequest(PurchaseRequest request) {
        if (request.getAmount() <= 10000) {
            System.out.println("主任 " + name + " 批准了采购单：金额 " + request.getAmount() + " 元，用途：" + request.getPurpose());
        } else if (nextApprover != null) {
            nextApprover.approveRequest(request);
        }
    }
}

// 部门经理审批类
class DepartmentManager extends Approver {
    public DepartmentManager(String name) {
        super(name);
    }

    @Override
    public void approveRequest(PurchaseRequest request) {
        if (request.getAmount() <= 50000) {
            System.out.println("部门经理 " + name + " 批准了采购单：金额 " + request.getAmount() + " 元，用途：" + request.getPurpose());
        } else if (nextApprover != null) {
            nextApprover.approveRequest(request);
        }
    }
}

// 副总经理审批类
class VicePresident extends Approver {
    public VicePresident(String name) {
        super(name);
    }

    @Override
    public void approveRequest(PurchaseRequest request) {
        if (request.getAmount() <= 100000) {
            System.out.println("副总经理 " + name + " 批准了采购单：金额 " + request.getAmount() + " 元，用途：" + request.getPurpose());
        } else if (nextApprover != null) {
            nextApprover.approveRequest(request);
        }
    }
}

// 总经理审批类
class President extends Approver {
    public President(String name) {
        super(name);
    }

    @Override
    public void approveRequest(PurchaseRequest request) {
        if (request.getAmount() <= 200000) {
            System.out.println("总经理 " + name + " 批准了采购单：金额 " + request.getAmount() + " 元，用途：" + request.getPurpose());
        } else if (nextApprover != null) {
            nextApprover.approveRequest(request);
        }
    }
}

// 职工大会审批类
class StaffMeeting extends Approver {
    public StaffMeeting() {
        super("职工大会");
    }

    @Override
    public void approveRequest(PurchaseRequest request) {
        System.out.println("采购单金额 " + request.getAmount() + " 元，需要召开职工大会进行审批。");
    }
}

// 测试类
public class Main {
    public static void main(String[] args) {
        // 创建审批者对象
        Approver director = new Director("张主任");
        Approver departmentManager = new DepartmentManager("李经理");
        Approver vicePresident = new VicePresident("王副总");
        Approver president = new President("赵总");
        Approver staffMeeting = new StaffMeeting();

        // 构建职责链
        director.setNextApprover(departmentManager);
        departmentManager.setNextApprover(vicePresident);
        vicePresident.setNextApprover(president);
        president.setNextApprover(staffMeeting);

        // 创建采购请求
        PurchaseRequest request1 = new PurchaseRequest(8000, "办公用品采购");
        PurchaseRequest request2 = new PurchaseRequest(30000, "项目设备采购");
        PurchaseRequest request3 = new PurchaseRequest(70000, "大型设备采购");
        PurchaseRequest request4 = new PurchaseRequest(150000, "建筑材料采购");
        PurchaseRequest request5 = new PurchaseRequest(300000, "重大项目采购");

        // 发起审批请求
        director.approveRequest(request1);
        director.approveRequest(request2);
        director.approveRequest(request3);
        director.approveRequest(request4);
        director.approveRequest(request5);
    }
}