中介者模式

在“虚拟聊天室”实例中增加一个新的具体聊天室类和一个新的具体会员类，要求如下：

1. 新的具体聊天室中发送的图片大小不得超过20M。

2. 新的具体聊天室中发送的文字长度不得超过100个字符。

3. 新的具体会员类可以发送图片信息和文本信息。

4. 新的具体会员类在发送文本信息时，可以在信息后加上时间。

修改客户端测试类，注意原有系统类代码和客户端代码的修改。

package org.Mediator;


public abstract class AbstractChatroom {
    public abstract void register(Member member);
    public abstract void sendText(String from,String to,String message);
    public abstract void sendImage(String from,String to,String image);
}

package org.Mediator;

import java.util.HashMap;
import java.util.Hashtable;

public class ChatGroup extends AbstractChatroom{
    private Hashtable members=new Hashtable();

    @Override
    public void register(Member member) {
        if(!members.contains(member)){
            members.put(member.getName(),member);
            member.setChatroom(this);
        }
    }

    @Override
    public void sendText(String from, String to, String message) {
        Member member= (Member) members.get(to);
        if(message.length()>100){
            System.out.println("文字过长，发送失败！");
        }else{
            member.receiveText(from,message);
        }
    }

    @Override
    public void sendImage(String from, String to, String image) {
        Member member= (Member) members.get(to);
        if(image.length()>20){
            System.out.println("图片过大，发送失败！");
        }else{
            member.receiveImage(from,image);
        }
    }
}

package org.Mediator;

public abstract class Member {
    protected AbstractChatroom chatroom;
    protected String name;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Member(String name){
        this.name=name;

    }

    public AbstractChatroom getChatroom() {
        return chatroom;
    }

    public void setChatroom(AbstractChatroom chatroom) {
        this.chatroom = chatroom;
    }

    public abstract void sendText(String to,String message);
    public abstract void sendImage(String to,String image);

    public void receiveText(String from,String message){
        System.out.println(from+"发送文本给"+this.name+"，内容为："+message);
    }

    public void receiveImage(String from,String image){
        System.out.println(from+"发送图片给"+this.name+"，内容为："+image);
    }
}

package org.Mediator;

public class DiamondMember extends Member{
    public DiamondMember(String name) {
        super(name);
    }

    @Override
    public void sendText(String to, String message) {
        System.out.println("会员发送信息：");
        chatroom.sendText(name,to,message);
    }

    @Override
    public void sendImage(String to, String image) {
        System.out.println("会员发送图片：");
        chatroom.sendImage(name,to,image);
    }
}

package org.Mediator;

public class Client {
    public static void main(String[] args) {
        AbstractChatroom chatroom=new ChatGroup();

        Member member1,member2,member3,member4,member5;
        member1=new DiamondMember("笑意");
        member2=new DiamondMember("晓贰");
        member3=new DiamondMember("消散");
        member4=new DiamondMember("小肆");
        member5=new DiamondMember("小伍");

        chatroom.register(member1);
        chatroom.register(member2);
        chatroom.register(member3);
        chatroom.register(member4);
        chatroom.register(member5);

        member1.sendText("晓贰","晓贰，你好");
        member2.sendText("笑意","笑意，你好");
        member3.sendImage("小肆","好大的太阳");
        member4.sendImage("消散","**********************************************************");
        member5.sendText("消散","*********************************************************" +
                "************************************************************************************" +
                "************************************************************************************" +
                "************************************************************************************");
    }
}