chatprotocolhandler.java

用Mina 实现 简单聊天功能 相当于Java C/S 结构 大家可以在此基础上去进行完善

package com.mina.chat.server;

import java.util.Collections;
import java.util.HashSet;
import java.util.Set;

import org.apache.mina.core.service.IoHandlerAdapter;
import org.apache.mina.core.session.IoSession;
import org.apache.mina.filter.logging.MdcInjectionFilter;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * 服务器端-负责处理连结上来的客户机，即消息处理器.
 *
 * @author 1
 * @version 1.0
 */
public class ChatProtocolHandler extends IoHandlerAdapter {
    private final Logger logger = LoggerFactory.getLogger(getClass());

    private final Set<IoSession> sessions = Collections
            .synchronizedSet(new HashSet<IoSession>());

    private final Set<String> users = Collections
            .synchronizedSet(new HashSet<String>());

    @Override
    public void exceptionCaught(IoSession session, Throwable cause) {
        logger.warn("Unexpected exception.", cause);
        
        session.close(true);
    }

    @Override
    public void messageReceived(IoSession session, Object message) {
        Logger log = LoggerFactory.getLogger(ChatProtocolHandler.class);
        log.info("received: " + message);
        String theMessage = (String) message;
        System.out.println("ChatProtocolhandler get Message is:" + theMessage);
        String[] result = theMessage.split(" ", 2);
        String theCommand = result[0];

        try {

            ChatCommand command = ChatCommand.valueOf(theCommand);
            String user = (String) session.getAttribute("user");

            switch (command.toInt()) {

            case ChatCommand.QUIT:
                session.write("QUIT OK");
                session.close(true);
                break;
            case ChatCommand.LOGIN:

                if (user != null) {
                    session.write("LOGIN ERROR user " + user
                            + " already logged in.");
                    return;
                }

                if (result.length == 2) {
                    user = result[1];
                } else {
                    session.write("LOGIN ERROR invalid login command.");
                    return;
                }

                // check if the userName is already used
                if (users.contains(user)) {
                    session.write("LOGIN ERROR the name " + user
                            + " is already used.");
                    return;
                }

                sessions.add(session);
                session.setAttribute("user", user);
                MdcInjectionFilter.setProperty(session, "user", user);

                // Allow all users
                users.add(user);
                session.write("LOGIN OK");
                broadcast("The user " + user + " has joined the chat session.");
                break;

            case ChatCommand.BROADCAST:

                if (result.length == 2) {
                    broadcast(user + ": " + result[1]);
                }
                break;
            default:
                logger.info("Unhandled command: " + command);
                break;
            }

        } catch (IllegalArgumentException e) {
            logger.debug("Illegal argument", e);
        }
    }

    public void broadcast(String message) {
        synchronized (sessions) {
            for (IoSession session : sessions) {
                if (session.isConnected()) {
                    session.write("BROADCAST OK " + message);
                }
            }
        }
    }

    @Override
    public void sessionClosed(IoSession session) throws Exception {
        String user = (String) session.getAttribute("user");
        users.remove(user);
        sessions.remove(session);
        broadcast("The user " + user + " has left the chat session.");
    }

    public boolean isChatUser(String name) {
        return users.contains(name);
    }

    public int getNumberOfUsers() {
        return users.size();
    }

    public void kick(String name) {
        synchronized (sessions) {
            for (IoSession session : sessions) {
                if (name.equals(session.getAttribute("user"))) {
                    session.close(true);
                    break;
                }
            }
        }
    }
}