Chat сървър

Клиент

import java.net.*;
import java.awt.*;
import java.io.*;
import java.awt.event.*;
import javax.swing.*;

public class Client {
    BufferedReader in;
    PrintWriter out;
    InetAddress addr;
    Socket socket;
    String name;
    Gui g;
    Client(JFrame f){
        init();
        g = new Gui(f);
    }
    class Gui{
        JTextArea serv;
        JTextField cl;
        Gui (JFrame f){
            f.setLayout(new BorderLayout());
            serv = new JTextArea(20,10);
            serv.setEditable(false);
            serv.setBackground(new Color(230,230,230));
            serv.setFont(new Font("SANS_SERIF", Font.BOLD, 14));
            cl = new JTextField(30);
            f.add("Center",new JScrollPane(serv));
            f.add("South",cl);
            cl.addActionListener(new SrvL());
            (new Rcv()).start();
        }
        class SrvL implements ActionListener{
            public void actionPerformed(ActionEvent e){
                try{
                    String st=cl.getText();
                    send(st);
                    cl.setText("");
                }
                catch (Exception ex){
                    System.out.println("exception: "+ex);
                    System.out.println("closing...");
                    try{
                        socket.close();
                    }
                    catch (Exception expt){
                        System.out.println(expt);
                    }
                }
            }
        }
        class Rcv extends Thread{
            public void run(){
                for(;;){
                    try {         
                        sleep(400);
                    } catch (InterruptedException e){}
                    try{
                        serv.append(in.readLine()+"\n");
                        serv.setCaretPosition(serv.getDocument().getLength());            
                    } catch (IOException e1){break;}
                }
                System.out.println(" closing reading thread...");
                try{
                    socket.close();
                }
                catch (Exception expt){
                    System.out.println(expt);
                }
                System.exit(0);
            }
        }
    }
    public void init(){
        try{
            do{
                name = JOptionPane.showInputDialog("Please enter your name");
            } while((name == null)|| (name.length()==0));
            String server = null;
            InetAddress addr = InetAddress.getByName(server);
            System.out.println("addr = " + addr);
            socket = new Socket(addr, ChatSrv.PORT);
            System.out.println("socket = " + socket);
            //BufferedReader sin = new BufferedReader(
            // new InputStreamReader(System.in));
            in =  new BufferedReader(
                    new InputStreamReader(socket.getInputStream()));
            // Output is automatically flushed
            // by PrintWriter:
            out = new PrintWriter(new BufferedWriter(
                    new OutputStreamWriter(socket.getOutputStream())),true);            
        }catch (Exception e){
            System.out.println("exception: "+e);
            System.out.println("closing...");
            try{
                socket.close();
            }catch (Exception e2){
                System.out.println("no server running");
                System.exit(5);
            }
        }
    }
    void send(String s){
        if(s.length()==0){
            int quit = JOptionPane.showConfirmDialog(null, "Exit chat");
            if(quit == 0) {
                out.println("END");
                System.out.println("closing...");
                try{
                    socket.close();
                }
                catch (Exception expt){
                    System.out.println(expt);
                }
                System.exit(0);
            }
        }
        else out.println(name+": "+s);
    }
    public static void main(String[] args )throws IOException{
        JFrame frame =new JFrame();
        frame.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
        Client cl = new Client(frame);
        frame.setTitle(cl.name + "  (empty line to exit)");
        frame.setSize(500,300);
        frame.setVisible(true);
    }
}

Chat сървър с ArrayList

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

class Clients{
    private ArrayList<PrintWriter>  pW;
    public Clients(){
        pW = new ArrayList<PrintWriter>(10);
    }
    public synchronized void addC(PrintWriter p){
        pW.add(p);
    }
    public synchronized void rmvC(PrintWriter p){
        pW.remove(p);
    }
    public synchronized void sendC(String s){
        Iterator<PrintWriter> itr = pW.iterator();
        while(itr.hasNext()) {
            PrintWriter p=(PrintWriter)itr.next();
            p.println(s);
        }      
    }
    public synchronized int nCl(){
        return pW.size();
    }

}
//...............................................................
class ServeOneClient extends Thread {
    private Socket socket;
    private BufferedReader in;
    private PrintWriter out;
    Clients clt;
    public ServeOneClient(Socket s,Clients clt)  throws IOException {
        socket = s;
        this.clt =clt;
        in = new BufferedReader(
                new InputStreamReader(
                        socket.getInputStream()));
        // Enable auto-flush:
            out = new PrintWriter( new BufferedWriter(
                    new OutputStreamWriter(
                            socket.getOutputStream()
                            )
                    ),
                    true);
            // If any of the above calls throw an
            // exception, the caller is responsible for
            // closing the socket. Otherwise the thread
            // will close it.
            clt.addC(out);
            start();    // Calls run()
    }
    public void run() {
        try {
            while (true) {
                String str = in.readLine();
                if (str.equals("END")) break;
                System.out.println(str);
                clt.sendC(str);
            }

        } catch (IOException e) {  }
        finally {
            try {
                clt.rmvC(out);
                System.out.println("disconect a client. Total number "+clt.nCl());
                socket.close();
            } catch(IOException e) {}
        }
    }
}
//................................................................................
public class ChatSrv {
    static final int PORT = 9090;
    public static void main(String[] args) throws IOException {
        ServerSocket s = new ServerSocket(PORT);
        System.out.println("Server Started");
        Clients clt = new Clients();
        try {
            while(true) {
                // Blocks until a connection occurs:
                Socket socket = s.accept();
                try {
                    new ServeOneClient(socket,clt);
                    System.out.println("join a new client - total number "+ clt.nCl());
                } catch(IOException e) {
                    // If it fails, close the socket,
                    // otherwise the thread will close it:
                    socket.close();
                }
            }
        } finally {
            s.close();
        }
    }
}

Chat сървър с масив

import java.io.*;
import java.net.*;
class ClientsA{
    private int size;
    private PrintWriter pW[];
    public ClientsA(){
        pW = new PrintWriter[10];
        size=0;
    }
    public synchronized void addC(PrintWriter p){
        if(size==pW.length){
            PrintWriter buf[]=new PrintWriter[pW.length*2];
            System.arraycopy(pW,0,buf,0,pW.length);
            pW=buf;
        }
        pW[size++]=p;
    }
    public synchronized void rmvC(PrintWriter p){
        for(int i=0;i<pW.length;i++){
            if(pW[i]==p){
                pW[i]=pW[size--];                
                break;
            }
        }
    }
    public synchronized void sendC(String s){
        for(int i=0;i<size;i++){
            pW[i].println(s);
        }
    }
    public synchronized int nCl(){
        return size;
    }
}
//.................................................................................................
class ServeOneClientA extends Thread {
    private Socket socket;
    private BufferedReader in;
    private PrintWriter out;
    ClientsA clt;
    public ServeOneClientA(Socket s,ClientsA clt)  throws IOException {
        socket = s;
        this.clt =clt;
        in = new BufferedReader(
                new InputStreamReader(
                        socket.getInputStream()));
        // Enable auto-flush:
            out = new PrintWriter( new BufferedWriter(
                    new OutputStreamWriter(
                            socket.getOutputStream()
                            )
                    ),
                    true);
            // If any of the above calls throw an
            // exception, the caller is responsible for
            // closing the socket. Otherwise the thread
            // will close it.
            clt.addC(out);
            start();    // Calls run()
    }
    public void run() {
        try {
            while (true) {
                String str = in.readLine();
                if (str.equals("END")) break;
                System.out.println(str);
                //out.println(str+" total:"+c.getC());
                clt.sendC(str);
            }
        } catch (IOException e) {  }
        finally {
            try {
                clt.rmvC(out);
                System.out.println("disconect a client. Total number "+clt.nCl());
                socket.close();
            } catch(IOException e) {}
        }
    }
}
//.....................................................................................................................
public class ChatSrvA {
    static final int PORT = 9090;
    public static void main(String[] args) throws IOException {
        ServerSocket s = new ServerSocket(PORT);
        System.out.println("Server Started");
        Clients clt = new Clients();
        try {
            while(true) {
                // Blocks until a connection occurs:
                Socket socket = s.accept();
                try {
                    new ServeOneClient(socket,clt);
                } catch(IOException e) {
                    // If it fails, close the socket,
                    // otherwise the thread will close it:
                    socket.close();
                }
            }
        } finally {
            s.close();
        }
    }
}