責任鏈模式

 先附上代碼：

 

package com.hbq.chain;

import java.util.ArrayList;
import java.util.Random;

interface IWomen
{
    public int getType();
    public String getRequest();
}

class Women implements IWomen
{
    private int type = 0 ;
    private String request = "" ;

    public Women(int type,String req)
    {
        this.type = type ;
        switch(this.type)
        {
        case 1:
            this.request = "女兒的請求是："+req ;
            break;
        case 2:
            this.request = "妻子的請求是："+req ;
            break;
        case 3:
            this.request = "母親的請求是："+req ;
            break;
        }
    }

    @Override
    public int getType() {
        // TODO Auto-generated method stub
        return this.type;
    }

    @Override
    public String getRequest() {
        // TODO Auto-generated method stub
        return this.request;
    }

}

public abstract class Handler {
    private int level = 0 ;
    private Handler next = null ;

    public Handler(int l,Handler n)
    {
        this.level = l ;
        this.next = n ;
    }

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

    public void setNext(Handler next)
    {
        this.next = next ;
    }

    public abstract void response(IWomen women);

    /*每個環節只有2個選項：要麼承擔責任作出迴應，要麼向下傳*/
    public void handleMsg(IWomen women)
    {
        if(this.level == women.getType())
            this.response(women);
        else
        {
            if( this.next != null )
            {
                this.next.handleMsg(women);
            }
            else
                System.out.println("-----------沒有地方請示了，不做處理！-----------\n");
        }
    }
}

class Father extends Handler
{

    public Father() {
        super(1);
        // TODO Auto-generated constructor stub
    }

    @Override
    public void response(IWomen women) {
        // TODO Auto-generated method stub
        System.out.println("-----------女兒向父親請示------------");
        System.out.println(women.getRequest());
        System.out.println("父親的回答是：同意\n");
    }

}

class Son extends Handler
{

    public Son() {
        super(3);
        // TODO Auto-generated constructor stub
    }

    @Override
    public void response(IWomen women) {
        // TODO Auto-generated method stub
        System.out.println("-----------母親向兒子請示------------");
        System.out.println(women.getRequest());
        System.out.println("兒子的回答是：同意\n");
    }

}

class Husband extends Handler
{

    public Husband() {
        super(2);
        // TODO Auto-generated constructor stub
    }

    @Override
    public void response(IWomen women) {
        // TODO Auto-generated method stub
        System.out.println("-----------妻子向丈夫請示------------");
        System.out.println(women.getRequest());
        System.out.println("丈夫的回答是：同意\n");
    }

}

class client
{
    public static void main(String[] args)
    {
        /*隨機設置一些Women*/
        Random rand = new Random();
        ArrayList<IWomen> arrayList = new ArrayList();

        for( int i = 0 ; i < 5 ; i++)
        {
            int j = rand.nextInt(4) ;
            arrayList.add(new Women(j,"我要出去逛街"));
            //System.out.print(j);
        }

        //System.out.println("\n");


        Father father = new Father();
        Son son = new Son();
        Husband husband = new Husband();

        father.setNext(husband);
        husband.setNext(son);

        for( IWomen women:arrayList)
        {
            /*在責任鏈模式下，不用關注最終處理的對象是誰，由鏈表的形式往下傳*/
            father.handleMsg(women);
        }
    }
}