Java设计模式之责任链模式

/**
 * @version v1.0
 * @ClassName: LeaveRequest
 * @Description: 请假条类
 * @Author: 黑马程序员
 */
public class LeaveRequest {
    //姓名
    private String name;

    //请假天数
    private int num;

    //请假内容
    private String content;

    public LeaveRequest(String name, int num, String content) {
        this.name = name;
        this.num = num;
        this.content = content;
    }

    public String getName() {
        return name;
    }

    public int getNum() {
        return num;
    }

    public String getContent() {
        return content;
    }
}


/**
 * @version v1.0
 * @ClassName: Handler
 * @Description: 抽象处理者类
 * @Author: 黑马程序员
 */
public abstract class Handler {

    protected final static int NUM_ONE = 1;
    protected final static int NUM_THREE = 3;
    protected final static int NUM_SEVEN = 7;

    //该领导处理的请假天数区间
    private int numStart;
    private int numEnd;

    //声明后续者（声明上级领导）
    private Handler nextHandler;

    public Handler(int numStart) {
        this.numStart = numStart;
    }

    public Handler(int numStart, int numEnd) {
        this.numStart = numStart;
        this.numEnd = numEnd;
    }

    //设置上级领导对象
    public void setNextHandler(Handler nextHandler) {
        this.nextHandler = nextHandler;
    }

    //各级领导处理请求条的方法
    protected abstract void handleLeave(LeaveRequest leave);

    //提交请求条
    public final void submit(LeaveRequest leave) {
        //该领导进行审批
        if (this.nextHandler != null && leave.getNum() > this.numEnd) {
            //提交给上级领导进行审批
            this.nextHandler.submit(leave);
        } else {
            this.handleLeave(leave);
            System.out.println("流程结束！");
        }
    }
}


/**
 * @version v1.0
 * @ClassName: GroupLeader
 * @Description: 小组长类（具体的处理者）
 * @Author: 黑马程序员
 */
public class GroupLeader extends Handler {

    public GroupLeader() {
        super(0,Handler.NUM_ONE);
    }

    protected void handleLeave(LeaveRequest leave) {
        System.out.println(leave.getName() + "请假" + leave.getNum() + "天，" + leave.getContent() + "。");
        System.out.println("小组长审批：同意");
    }
}


/**
 * @version v1.0
 * @ClassName: GroupLeader
 * @Description: 部门经理类（具体的处理者）
 * @Author: 黑马程序员
 */
public class Manager extends Handler {

    public Manager() {
        super(Handler.NUM_ONE,Handler.NUM_THREE);
    }

    protected void handleLeave(LeaveRequest leave) {
        System.out.println(leave.getName() + "请假" + leave.getNum() + "天，" + leave.getContent() + "。");
        System.out.println("部门经理审批：同意");
    }
}


/**
 * @version v1.0
 * @ClassName: GroupLeader
 * @Description: 总经理类（具体的处理者）
 * @Author: 黑马程序员
 */
public class GeneralManager extends Handler {

    public GeneralManager() {
        super(Handler.NUM_THREE,Handler.NUM_SEVEN);
    }

    protected void handleLeave(LeaveRequest leave) {
        System.out.println(leave.getName() + "请假" + leave.getNum() + "天，" + leave.getContent() + "。");
        System.out.println("总经理审批：同意");
    }
}

/**
 * @version v1.0
 * @ClassName: Client
 * @Description: TODO(一句话描述该类的功能)
 * @Author: 黑马程序员
 */
public class Client {
    public static void main(String[] args) {
        //创建一个请假条对象
        LeaveRequest leave = new LeaveRequest("小明",5,"身体不适");

        //创建各级领导对象
        GroupLeader groupLeader = new GroupLeader();
        Manager manager = new Manager();
        GeneralManager generalManager = new GeneralManager();

        //设置处理者链
        groupLeader.setNextHandler(manager);
        manager.setNextHandler(generalManager);


        //小明提交请假申请
        groupLeader.submit(leave);
    }
}