工单管理系统java源码

工单是指在企业或组织中，员工或用户提出的需求或问题，需要由相关人员进行处理和解决的事务。工单管理系统是一种用于管理和跟踪工单的软件系统，能够帮助企业或组织高效地处理工单，提高工作效率。

本文将介绍一个使用Java语言编写的简单工单管理系统的源码，以及相关的代码示例。该系统包含了工单的创建、分配、处理和关闭等功能，以及一些基本的查询和统计功能。

首先，我们来看一下系统的类图：

classDiagram
    class WorkOrder {
        -id: int
        -title: String
        -description: String
        -status: String
        -createDate: Date
        -assignee: User
        -handler: User
        -closeDate: Date
        +WorkOrder(id: int, title: String, description: String)
        +getId(): int
        +getTitle(): String
        +getDescription(): String
        +getStatus(): String
        +getCreateDate(): Date
        +getAssignee(): User
        +getHandler(): User
        +getCloseDate(): Date
        +setStatus(status: String): void
        +setAssignee(assignee: User): void
        +setHandler(handler: User): void
        +setCloseDate(closeDate: Date): void
    }
    class User {
        -id: int
        -name: String
        -email: String
        -role: String
        +User(id: int, name: String, email: String, role: String)
        +getId(): int
        +getName(): String
        +getEmail(): String
        +getRole(): String
    }
    class WorkOrderManagementSystem {
        -workOrders: List<WorkOrder>
        -users: List<User>
        +createWorkOrder(title: String, description: String): void
        +assignWorkOrder(workOrder: WorkOrder, assignee: User): void
        +handleWorkOrder(workOrder: WorkOrder, handler: User): void
        +closeWorkOrder(workOrder: WorkOrder): void
        +getAssignedWorkOrders(assignee: User): List<WorkOrder>
        +getHandledWorkOrders(handler: User): List<WorkOrder>
        +getClosedWorkOrders(): List<WorkOrder>
    }
    WorkOrder "1" -- "1" User : assignee
    WorkOrder "1" -- "1" User : handler
    WorkOrderManagementSystem "1" -- "0..*" WorkOrder
    WorkOrderManagementSystem "1" -- "0..*" User

接下来，我们将介绍系统中关键的几个类和其代码实现。

1. WorkOrder类：工单类，用于表示一个工单。该类包含了工单的id、标题、描述、状态、创建日期、分配人、处理人和关闭日期等属性。具体代码如下：

public class WorkOrder {
    private int id;
    private String title;
    private String description;
    private String status;
    private Date createDate;
    private User assignee;
    private User handler;
    private Date closeDate;

    public WorkOrder(int id, String title, String description) {
        this.id = id;
        this.title = title;
        this.description = description;
        this.status = "Created";
        this.createDate = new Date();
    }

    public int getId() {
        return id;
    }

    public String getTitle() {
        return title;
    }

    public String getDescription() {
        return description;
    }

    public String getStatus() {
        return status;
    }

    public Date getCreateDate() {
        return createDate;
    }

    public User getAssignee() {
        return assignee;
    }

    public User getHandler() {
        return handler;
    }

    public Date getCloseDate() {
        return closeDate;
    }

    public void setStatus(String status) {
        this.status = status;
    }

    public void setAssignee(User assignee) {
        this.assignee = assignee;
    }

    public void setHandler(User handler) {
        this.handler = handler;
    }

    public void setCloseDate(Date closeDate) {
        this.closeDate = closeDate;
    }
}

2. User类：用户类，用于表示系统中的用户。用户类包含了用户的id、姓名、电子邮件和角色等属性。具体代码如下：

public class User {
    private int id;
    private String name;
    private String email;
    private String role;

    public User(int id, String name, String email, String role) {
        this.id = id;
        this.name = name;
        this.email = email;
        this.role = role;
    }

    public int getId() {
        return id;
    }

    public String getName