Java socket programming for group chat and private chat [schematic]

Brief introduction

using Java Sockets we can almost complete a web chat software small product, this article does not involve the UI part, only for the principle part of the code to demonstrate. A small, multi-person chat feature that is available on Linux systems with telnet affinity.

Server code

Package Demo0811.demo3;import Java.io.outputstream;import Java.net.serversocket;import java.net.Socket;import Java.util.arraylist;import Java.util.concurrent.executorservice;import java.util.concurrent.executors;/** * Use multithreading to write a server with port number 9999 * @author ZZW * */public class Servermain {public static arraylist<integer> ports=new ArrayList <Integer> ();p ublic static arraylist<outputstream> streams=new arraylist<outputstream> ();p ublic static void Main (string[] args) {try (ServerSocket server=new serversocket (9999)) {System.out.println ("server is Running"); Executorservice Newfixedthreadpool = Executors.newfixedthreadpool (+), while (true) {Socket socket = server.accept (); int port = Socket.getport (), OutputStream outputstream = Socket.getoutputstream ();p Orts.add (port); Streams.add ( OutputStream); Newfixedthreadpool.submit (new Socketrunnable (Socket,outputstream)); Newfixedthreadpool.submit (new Notifynewersrunnable (port));}} catch (Exception ex) {System.out.println ("Unable to establish monitoring service! "); ex.printstacktrAce ();} }}

Package Demo0811.demo3;import Java.io.bufferedreader;import Java.io.ioexception;import java.io.InputStream;import Java.io.inputstreamreader;import Java.io.outputstream;import Java.io.outputstreamwriter;import Java.net.Socket; Import Java.util.date;public class Socketrunnable implements Runnable {private Socket socket;private OutputStream Outputstream;public socketrunnable (Socket socket,outputstream outputstream) {this.socket=socket;this.outputstream= OutputStream;} @Overridepublic void Run () {try {outputstreamwriter outputstreamwriter = new OutputStreamWriter (outputstream);D ate Date = new Date (); Outputstreamwriter.write (date.tostring () + "\ n if sending private messages, use [port] to start with" + "\ r \ n"); Outputstreamwriter.flush (); int port = Socket.getport (), while (true) {if (socket.isconnected ()) {InputStream InputStream = Socket.getinputstream (); I Nputstreamreader reader = new InputStreamReader (InputStream, "UTF-8"); BufferedReader BufferedReader = new BufferedReader (reader); String Line;while ((Line=bufferedreader.readline ())!=null) {if (Line.startswith (")") {int end=line.indexof ('] '); int Target=integer.parseint (line.substring (1, end)); int IndexOf = ServerMain.ports.indexOf (target); if (end<0| | indexof<0) {OutputStreamWriter outputStreamWriter2 = new OutputStreamWriter (ServerMain.streams.get ( ServerMain.ports.indexOf (Port), "UTF-8"); Outputstreamwriter2.write ("Your private message format is incorrectly entered or the port number does not exist!") \ r \ n "); Outputstreamwriter2.flush ();} else {OutputStreamWriter OutputStreamWriter2 = new OutputStreamWriter (ServerMain.streams.get (indexOf), "UTF-8"); o Utputstreamwriter2.write ("Port" +port+ "Private Messages:" +line.substring (end+1) + "\ r \ n"); Outputstreamwriter2.flush ();}} else {for (int i=0;i<servermain.streams.size (); i++) {try {outputstreamwriter outputStreamWriter2 = new OutputStreamWriter (ServerMain.streams.get (i), "UTF-8"); Outputstreamwriter2.write ("Port" +port+ "group chat:" +line+ "\ n"); o Utputstreamwriter2.flush ();} catch (IOException e) {e.printstacktrace ();}}}} else {break;}} Socket.close ();} catch (IOException e) {System.out.println ("The server cannot write data to the client!") "); e.printstacktrAce ();} Finally {try {socket.close ();} catch (IOException e) {//Not processed}}}

Package Demo0811.demo3;import Java.io.ioexception;public class notifynewersrunnable implements Runnable{private int Port;public notifynewersrunnable (int port) {this.port = port;} @Overridepublic void Run () {int n; String str= "Port" +port+ "on line \ r \ n"; if ((N=servermain.streams.size ()) >1) {for (int i=0;i<n-1;i++) {try { ServerMain.streams.get (i). Write (Str.getbytes ("Utf-8")); ServerMain.streams.get (i). Flush ();} catch (IOException e) {e.printstacktrace ();}}}}

Java socket programming for group chat and private chat [schematic]