C/S聊天程序(JAVA,C/S)

import java.io.*; import java.net.*; import java.util.*; public class ChatServer { protected final static String CHATMASTER_ID="ChatMaster"; protected final static String SEP=":"; protected ServerSocket servSock; protected ArrayList clients; private static boolean DEBUG=false; public static void main(String[] argv){ System.out.println("Chat Server 0.1 starting..."); if(argv.length==1&&argv[0].equals("-debug"))DEBUG=true; ChatServer w=new ChatServer(); w.runServer(); System.out.println("**ERROR*Chat Server 0.1 quitting"); } ChatServer(){ clients=new ArrayList(); try{ servSock=new ServerSocket(Chat.PORTNUM); System.out.println("Chat Server Listening on port"+ Chat.PORTNUM); } catch(IOException e) { log("IO Exception in ChatServer.<init>"); System.exit(0); } } public void runServer() { try{ while(true){ Socket us=servSock.accept(); String hostName=us.getInetAddress().getHostName(); System.out.println("Accepted from "+hostName); ChatHandler c1=new ChatHandler(us,hostName); synchronized(clients) { clients.add(c1); c1.start(); if(clients.size()==1)c1.send(CHATMASTER_ID,"Welcome! you'er the first one here"); else{c1.send(CHATMASTER_ID,"Welcome! you're the latest of"+clients.size()+"users"); } } } }catch(IOException e){ log("IO Exception in runServer:"+e); System.exit(0); } } protected void log(String s) { System.out.println(s); } protected class ChatHandler extends Thread{ protected Socket clientSock; protected BufferedReader is; protected PrintWriter pw; protected String clientIP; protected String login; public ChatHandler(Socket sock,String clnt)throws IOException { clientSock=sock; clientIP=clnt; is=new BufferedReader(new InputStreamReader(sock.getInputStream())); pw=new PrintWriter(sock.getOutputStream(),true); } public void run(){ String line; try{ while((line=is.readLine())!=null){ char c=line.charAt(0); line=line.substring(1); switch(c){ case Chat.CMD_LOGIN: if(!Chat.isValidLoginName(line)){ send(CHATMASTER_ID,"LOGIN"+line+"invalid"); log("LOGININVALID from"+clientIP); continue; } login=line; broadcast(CHATMASTER_ID,login+"joins us,for a total of"+clients.size()+"uses"); break; case Chat.CMD_MESG: if(login==null){ send(CHATMASTER_ID,"please login first"); continue; } int where=line.indexOf(Chat.SEPARATOR); String recip=line.substring(0,where); String mesg=line.substring(where+1); log("MESG:"+login+"-->"+recip+":"+mesg); ChatHandler c1=lookup(recip); if(c1==null)psend(CHATMASTER_ID,"not logged in."); else c1.psend(login,mesg); break; case Chat.CMD_QUIT: broadcast(CHATMASTER_ID,"Goodbye to"+login+"@"+clientIP); close(); return; case Chat.CMD_BCAST: if(login!=null)broadcast(login,line); else log("B<L from"+clientIP); break; default: log("Unknown cmd"+"from"+login+"@"+clientIP); } } } catch(IOException e){log("IO Exception:"+e);} finally{ System.out.println(login+SEP+"All Done"); synchronized(clients){ clients.remove(this); if(clients.size()==0){System.out.println(CHATMASTER_ID+SEP+"Im so lonely I could cry...");} else if(clients.size()==1){ChatHandler last=(ChatHandler)clients.get(0); last.send(CHATMASTER_ID,"Hey,you're talking to yourself again");} else {broadcast(CHATMASTER_ID,"There are now"+clients.size()+"users"); } } } } protected void close(){ if(clientSock==null){ log("close when not open"); return; } try{ clientSock.close(); clientSock=null; } catch(IOException e){log("Failure during close to"+clientIP); } } public void send(String sender,String mesg){ pw.println(sender+SEP+mesg); } protected void psend(String sender,String msg){ send("<"+sender+"*>",msg); } public void broadcast(String sender,String mesg){ System.out.println("Broadcasting"+sender+SEP+mesg); for(int i=0;i<clients.size();i++){ ChatHandler sib=(ChatHandler)clients.get(i); if(DEBUG)System.out.println("Sending to "+sib); sib.send(sender,mesg);} if(DEBUG)System.out.println("Done broadcast"); } protected ChatHandler lookup(String nick){ synchronized(clients){ for(int i=0;i<clients.size();i++){ ChatHandler c1=(ChatHandler)clients.get(i); if(c1.login.equals(nick))return c1; } } return null; } public String toString() { return "ChatHandler["+login+"]"; } } }