socketserver.java

一个用java 编写的可以和多个人聊天的服务器

package chat.socket;

import chat.*;

import java.io.*;
import java.net.*;

public class SocketServer extends BaseServer
{
	public final static int PORT_NUMBER = 2222; // Our chat application port
	
	// Invoke type of method to be called
	public final static int INVOKE_GET_HISTORY = 0;
	public final static int INVOKE_BROADCAST = 1;
	public final static int INVOKE_GET_USER = 2;
	public final static int INVOKE_DISCONNECT = 3;

	// Status of logon
	public final static int LOGON_SUCCESSFUL = 0;
	public final static int LOGON_FAILED = -1;
	
	// Type of data to be sent
	public final static int SENT_MSG = 0;
	public final static int SENT_USER = 1;
	public final static int REMOVE_USER = 2;
	public final static int CLEAR_USER = 3;

	public static void main(String[] args) throws IOException
	{
		SocketServer ss = new SocketServer();
	}

	public SocketServer() throws IOException
	{
		Socket client;
		ServerSocket ss = new ServerSocket(PORT_NUMBER);
		while (true)
		{
			client = ss.accept();
			// Separate thread for different user
			SocketSkeleton skel = new SocketSkeleton(client);
			addClient(skel);
			skel.start();
		}
	}

	// SocketSkeletion thread	
	class SocketSkeleton extends Thread implements ChatClient
	{
		protected Socket receiveSocket;
		protected Socket sendSocket;

		protected DataInputStream inInput;
		protected DataOutputStream inOutput;
		
		protected DataOutputStream outOutput;
		
		public SocketSkeleton(Socket client)
		{
			receiveSocket = client;
		}

		public void run()
		{
			int methodID;
			try
			{
				String userid = initialize();
				broadcastUser(userid);
				while(true)
				{
					methodID = inInput.readInt();
					switch(methodID)
					{
						case INVOKE_BROADCAST: 	handleBroadcast();
									break;
						case INVOKE_GET_HISTORY: handleGetHistory();
									 break;
						case INVOKE_GET_USER: handleGetUser();
									break;
						case INVOKE_DISCONNECT: handleDisconnectUser();
									break;
					}
					/*if (methodID<0)
					{
						handleDisconnectUser();
					}*/
				}
			}catch (Exception ioe) {}
		}

		protected void handleBroadcast() throws IOException
		{
			String message = inInput.readUTF();
			broadcastMessage(message);
			addMessageToLog(message);
		}
		
		protected void handleGetHistory() throws IOException
		{
			ChatMessage message;
			java.util.Date msgDate;
			String msgText;

			int count = messageHistory.size();
			inOutput.writeInt(count);
			for (int i = 0; i < count; i++)
			{
				message = (ChatMessage) (messageHistory.elementAt(i));
				msgDate = message.messageDate;
				msgText = message.messageText;
				inOutput.writeLong( msgDate.getTime());
				inOutput.writeUTF(msgText);
			}
		}

		protected void handleGetUser() throws IOException
		{
			String user;
			int count = userServerList.size();
			inOutput.writeInt(count);
			for (int i=0; i < count; i++)
			{
				user = (String) (userServerList.elementAt(i));
				inOutput.writeUTF(user);
			}
		}

		protected void handleDisconnectUser() throws IOException
		{
			// Method to remove user from list
			// kill this thread
			String user = inInput.readUTF();
			removeClient(this);
			broadcastRemovedUser(user);
			System.out.println("Exit : " + user + " has left the server!");
			//destroy();
		}

		protected String initialize() throws IOException, LogonFailedException
		{
			InputStream is;
			OutputStream os;
			InetAddress addr;

			is = receiveSocket.getInputStream();
			inInput = new DataInputStream(is);
			os = receiveSocket.getOutputStream();
			inOutput = new DataOutputStream(os);
			String userid = inInput.readUTF();
			String password = inInput.readUTF();
			int sendPort = inInput.readInt();
			addr = receiveSocket.getInetAddress();

			if (isValidUserInfo(userid, password))
			{
				inOutput.writeInt(LOGON_SUCCESSFUL);
				sendSocket = new Socket(addr, sendPort);
				os = sendSocket.getOutputStream();
				outOutput = new DataOutputStream(os);
				System.out.println("(" + addr.toString() + ") : " + userid + " has joined the server!");
			}
			else
			{
				inOutput.writeInt(LOGON_FAILED);
				throw new LogonFailedException("Invalid userid / password");
			}
			return userid;
		}	

		public void displayMessage(ChatMessage message) throws IOException
		{
			java.util.Date msgDate = message.messageDate;
			long timeValue = msgDate.getTime();
			String msgText = message.messageText;
			outOutput.writeInt(SENT_MSG);
			outOutput.writeLong(timeValue);
			outOutput.writeUTF(msgText);
		}

		// Overwrite methods
		public void addUser(String id) throws Exception
		{
			outOutput.writeInt(SENT_USER);
			outOutput.writeUTF(id);
		}
		public void removeUser(String id) throws Exception
		{
			outOutput.writeInt(REMOVE_USER);
			outOutput.writeUTF(id);
		}
		public void clearUser() throws Exception
		{
			outOutput.writeInt(CLEAR_USER);
		}


	}
}