Socket

Ah effectivement, je n'avais pas vu ce point. Il vaudrait mieux que tu utilises les méthodes de haut niveau de ObjectOutputStream, c'est à dire writeObject, writeInteger, writeUTF, etc.

Je viens d'essayer ton code, et il fonctionne bien, la seule chose qui pourrait coincer c'est tes méthode encrypt et decrypt.

Voici deux classes complètes pour tester :

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.ObjectOutputStream;
import java.net.ServerSocket;
import java.net.Socket;

public class Server
{
    private static byte[] encrypt(byte[] tab)
    {
        return tab;
    }
    
    public static void main(String[] args) throws IOException
    {
        Socket sock = new ServerSocket(9001).accept();
        
        FileInputStream in = new FileInputStream(new File("C:/test.txt")); 
        ObjectOutputStream out = new ObjectOutputStream(sock.getOutputStream());
        
        byte buf[] = new byte[1024]; 
        int n; 
        while((n=in.read(buf))!=-1)
            out.write(encrypt(buf),0,n);

        out.close();
        in.close();
        sock.close();
    }
}

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.net.InetAddress;
import java.net.Socket;

public class Client
{    
    private static byte[] decrypt(byte[] tab)
    {
        return tab;
    }
    
    public static void main(String[] args) throws IOException
    {
        Socket sock = new Socket(InetAddress.getLocalHost(),9001);
        
        ObjectInputStream in=new ObjectInputStream(sock.getInputStream());
        FileOutputStream out = new FileOutputStream(new File("C:/test2.txt"));
        
        byte buf[] = new byte[1024]; 
        int n; 
        
        while((n=in.read(buf))!=-1)
            out.write(decrypt(buf),0,n);
        
        out.close();
        in.close();
        sock.close();
    }
}

Je n'avais pas compris que tu faisais plusieurs envois, le mieux serait que tu montres ton code complet pour te corriger.

import java.awt.BorderLayout;
import java.awt.Container;
import java.awt.Desktop;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.InetAddress;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.UnknownHostException;
import java.util.Map;

import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFileChooser;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JTextField;


public class ChatTransferServer extends JFrame implements ActionListener{

public static String nom_fichier; //pour le chemin du fichier
private JTextField file_path;
private JPanel pan= new JPanel(new GridLayout(2,1));
private JPanel pan_connexion= new JPanel(new GridLayout(3,2));

private JTextField address;
private JLabel name_address;
private JMenuBar fileMenuBar;
private JMenu fileMenu;
private JMenuItem filechoose;
private JMenuItem fileQuit;
private JButton btconnect = new JButton("connexion");
private JButton btFile = new JButton("encrypt file and send");
private JComboBox liste;
private JTextField connect;

private Container c ;
ByteArrayOutputStream bos = new ByteArrayOutputStream();
public static cryptage c1 ;
public File path;
public String clé_serveur;
ServerSocket servsock;
Socket sock;

/** Creates a new instance of Client */
public ChatTransferServer() {
super("Transfer secure file server");
//installation des composants graphique

//pour le menu
fileMenuBar = new JMenuBar();
fileMenu = new JMenu("Edit");
filechoose= new JMenuItem("Choose file");
fileQuit = new JMenuItem("Sign out");


fileMenuBar.add(fileMenu);
fileMenu.add(filechoose);
fileMenu.add(fileQuit);

//ajout des listeners
fileQuit.addActionListener(listenerquit);
filechoose.addActionListener(listenerchoose);
btFile.addActionListener(listenerbtFile);
btconnect.addActionListener(listenerbtconnect);

// sur le conteneur......
c = getContentPane();

Object[] elements = new Object[]{"Encryption Ceasare", "Advanced Encryption Ceasare (with thumbnail)"};
liste = new JComboBox(elements);

name_address= new JLabel("Peer Address");
address=new JTextField(10);
connect= new JTextField(10);
connect.setText("server disconnected");
try {
address.setText(InetAddress.getLocalHost().toString());
} catch (UnknownHostException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
file_path= new JTextField(15);
file_path.setFocusable(false);
pan_connexion.add(name_address);
pan_connexion.add(address);
pan_connexion.add(new JLabel(""));
pan_connexion.add(connect);
pan_connexion.add(new JLabel(""));
pan_connexion.add(btconnect);

pan.add(file_path);
// pan.add(this.liste);
pan.add(this.btFile);
c.add(pan,BorderLayout.SOUTH);
c.add(pan_connexion,BorderLayout.NORTH);

setSize(450,200);
setJMenuBar(fileMenuBar);
setVisible(true);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);




}


public String getcle(){
return clé_serveur;
}

public void setcle(String cle){
this.clé_serveur=cle;
}

ActionListener listenerbtFile = new ActionListener(){
@Override
public void actionPerformed(ActionEvent act) {
// TODO Auto-generated method stub


String nom=JOptionPane.showInputDialog(null,"Entrez la clé d'encryptage correspondante :","Saisie de la clé",JOptionPane.QUESTION_MESSAGE);
System.out.println("Server>> encryption and sending : clé "+ nom);
if (file_path.getText().compareTo("")==0)
System.out.println("please select a file..");


try
{

//envoi du nom du fichier
ObjectOutputStream sortie = new ObjectOutputStream(sock.getOutputStream());

// vidanger lengthtampon se sorie pour envoyer les information
//d'en-tête.
sortie.flush();


try{
sortie.writeObject(nom_fichier);
}
catch(NullPointerException e)
{

}
cryptage c = new cryptage(nom);
FileInputStream inf=new FileInputStream(new File(path.getAbsolutePath()));


ObjectOutputStream out=new ObjectOutputStream(sock.getOutputStream());

byte buf[] = new byte[1024];
int n;
while((n=inf.read(buf))!=-1){
out.write(buf,0,n);
}
// inf.close();
// out.reset();
// out.reset();

}

catch (NullPointerException e)
{
System.out.println("Serveur not connected");

} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}


}

};


ActionListener listenerbtconnect = new ActionListener(){
@Override
public void actionPerformed(ActionEvent act) {
// TODO Auto-generated method stub

try {
servsock = new ServerSocket(13267);

} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

System.out.println("Waiting...");
connect.setText("Waiting...");

try {
sock = servsock.accept();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
System.out.println("Accepted connection : " + sock);
connect.setText("server connected");

}};



ActionListener listenerquit = new ActionListener(){
@Override
public void actionPerformed(ActionEvent act) {
// TODO Auto-generated method stub
System.out.println(">>Exit");
try {
sock.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
System.exit(0);

}};


ActionListener listenerchoose = new ActionListener(){
@Override
public void actionPerformed(ActionEvent act) {
// TODO Auto-generated method stub
System.out.println(">>Choose a file");
System.out.println("LOG : Select a file ...");
file_path.setText("");
JFileChooser dirFileChooser = new JFileChooser();


String approve = new String("CHOOSE FILE");
// Le bouton pour valider l'enregistrement portera la

dirFileChooser.showDialog(dirFileChooser, approve); // Pour afficher le JFileChooser...

try{
System.out.println( dirFileChooser.getSelectedFile().getPath());

nom_fichier= dirFileChooser.getSelectedFile().getName();
path=dirFileChooser.getSelectedFile();

}
catch(NullPointerException e)
{
}
System.out.println("name of the file "+ nom_fichier);
file_path.setText("selected file: "+ nom_fichier);

try {
FileInputStream fis = new FileInputStream(dirFileChooser.getSelectedFile());
byte[] buffer = new byte[1024]; //Récupération du contenu du fichier dans une variable de type byte
// fis.read(buffer); //Lecture du contenu de la variable buffer


try {
for (int readNum; (readNum = fis.read(buffer)) != -1;) {
bos.write(buffer, 0, readNum); //no doubt here is 0
//Writes len bytes from the specified byte array starting at offset off to this byte array output stream.
System.out.println("read " + readNum + " bytes,");
}
} catch (IOException ex) {

}
} catch (IOException ex) {

}




}};

ActionListener listeneropen = new ActionListener(){
@Override
public void actionPerformed(ActionEvent act) {
// TODO Auto-generated method stub
System.out.println("LOG : Select a file ...");
JFileChooser dirFileChooser = new JFileChooser();



if(dirFileChooser.showOpenDialog(null) == JFileChooser.APPROVE_OPTION)
dirFileChooser.getSelectedFile();
System.out.println( dirFileChooser.getSelectedFile().getPath());
nom_fichier= dirFileChooser.getSelectedFile().getName();
System.out.println("name of the file"+ nom_fichier);

//ouverture du fichier
Desktop desk= Desktop.getDesktop();
try {
desk.open(dirFileChooser.getSelectedFile());
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

}};


@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub

}

public static void main(String[] args) {
ChatTransferServer appli = new ChatTransferServer();

}



}

et la le client

import java.awt.BorderLayout;
import java.awt.Container;
import java.awt.Desktop;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.Socket;
import java.net.UnknownHostException;

import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFileChooser;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.filechooser.FileFilter;


public class ChatTransferClient extends JFrame implements ActionListener{

private static String key;
public static String nom_fichier; //pour le chemin du fichier
private JTextField file_path;
private JPanel pan= new JPanel(new GridLayout(2,1));
private JPanel pan_connexion= new JPanel(new GridLayout(3,2));

private JTextField address;
private JLabel name_address;
private JMenuBar fileMenuBar;
private JMenu fileMenu;
private JMenuItem filechoose;
private JMenuItem fileQuit;
private JButton btconnect = new JButton("connexion");
private JButton btFile = new JButton("encrypt file and send");
private JButton btreceive = new JButton("Receive");
private JComboBox liste;
private JTextField connec;
private Container c ;

private String path;
ByteArrayOutputStream bos = new ByteArrayOutputStream();
static boolean connect=false;
static Socket sock;

public static String clé_client;
/** Creates a new instance of Client */
public ChatTransferClient() {
super("Transfer secure file client");
//installation des composants graphique
//pour le menu
fileMenuBar = new JMenuBar();
fileMenu = new JMenu("Edit");
filechoose= new JMenuItem("Choose file");
fileQuit = new JMenuItem("Sign out");


fileMenuBar.add(fileMenu);
fileMenu.add(filechoose);
fileMenu.add(fileQuit);

//ajout des listeners
fileQuit.addActionListener(listenerquit);
filechoose.addActionListener(listenerchoose);
btconnect.addActionListener(listenerbtconnect);
btreceive.addActionListener(listenerbtreceive);

// sur le conteneur......
c = getContentPane();

Object[] elements = new Object[]{"Encryption Ceasare", "Advanced Encryption Ceasare (with thumbnail)"};
liste = new JComboBox(elements);


name_address= new JLabel("Peer Address");
address=new JTextField(10);
connec=new JTextField(10);
file_path= new JTextField(15);
file_path.setFocusable(false);
pan_connexion.add(name_address);
pan_connexion.add(address);
pan_connexion.add(new JLabel(""));
pan_connexion.add(connec);
pan_connexion.add(new JLabel(""));
pan_connexion.add(btconnect);


pan.add(file_path);
// pan.add(this.liste);
pan.add(btreceive);
c.add(pan,BorderLayout.SOUTH);
c.add(pan_connexion,BorderLayout.NORTH);

setSize(450,200);
// setJMenuBar(fileMenuBar);
setVisible(true);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

connec.setText("client disconnected");


}


ActionListener listenerquit = new ActionListener(){
@Override
public void actionPerformed(ActionEvent act) {
// TODO Auto-generated method stub
System.out.println(">>Exit");
try {
sock.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
System.exit(0);

}};


ActionListener listenerchoose = new ActionListener(){
@Override
public void actionPerformed(ActionEvent act) {
// TODO Auto-generated method stub
System.out.println(">>Choose a file");
System.out.println("LOG : Select a file ...");
file_path.setText("");
JFileChooser dirFileChooser = new JFileChooser();


if(dirFileChooser.showOpenDialog(null) == JFileChooser.APPROVE_OPTION)
dirFileChooser.getSelectedFile();
try{
System.out.println( dirFileChooser.getSelectedFile().getPath());
nom_fichier= dirFileChooser.getSelectedFile().getName();

}
catch(NullPointerException e)
{

}
System.out.println("name of the file "+ nom_fichier);
file_path.setText("selected file: "+ nom_fichier);


try {
FileInputStream fis = new FileInputStream(dirFileChooser.getSelectedFile());
byte[] buffer = new byte[1024]; //Récupération du contenu du fichier dans une variable de type byte
// fis.read(buffer); //Lecture du contenu de la variable buffer

try {
for (int readNum; (readNum = fis.read(buffer)) != -1;) {
bos.write(buffer, 0, readNum); //no doubt here is 0
//Writes len bytes from the specified byte array starting at offset off to this byte array output stream.
System.out.println("read " + readNum + " bytes,");
}
} catch (IOException ex) {

}
} catch (IOException ex) {

}




}};



ActionListener listenerbtreceive = new ActionListener(){
@Override
public void actionPerformed(ActionEvent act) {
// TODO Auto-generated method stub


try
{
int filesize=6022386; // filesize temporary hardcoded

long start = System.currentTimeMillis();
int bytesRead;
int current = 0;
// localhost for testing


String nom=JOptionPane.showInputDialog(null,"Entrez la clé de decryptage correspondante :","Saisie de la clé",JOptionPane.QUESTION_MESSAGE);

//recuperation name file
ObjectInputStream entree = new ObjectInputStream(sock.getInputStream());
String message= "";
try
{
message = (String)entree.readObject();
}
catch (IOException e)
{

} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

System.out.println("le fichier est "+ message);
file_path.setText("Receiveé file "+message);
// receive file
byte [] mybytearray = new byte [filesize];
JFileChooser dirFileChooser = new JFileChooser();
String approve = new String("SAVE");
// Le bouton pour valider l'enregistrement portera la


dirFileChooser.setSelectedFile(new File (message));
if(dirFileChooser.showDialog(dirFileChooser, approve) == JFileChooser.APPROVE_OPTION)
dirFileChooser.getSelectedFile();
try{

System.out.println("Server>> decryption : clé "+ nom);
cryptage c = new cryptage(nom);


ObjectInputStream in=new ObjectInputStream(sock.getInputStream());


byte buf[] = new byte[1024];
int n=0;

FileOutputStream out =new FileOutputStream(new File(dirFileChooser.getSelectedFile().toString()));
// System.out.println(dirFileChooser.getSelectedFile().toString());
//ici pbleme
while((n=in.read(buf))!=-1){
out.write(buf,0,n);
}


// in.reset();
// out.close();


n=0;

}
catch(NullPointerException e)
{

}
}



catch (NullPointerException e)
{
System.out.println("client not connected");

} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

}

};


ActionListener listenerbtconnect = new ActionListener(){
@Override
public void actionPerformed(ActionEvent act) {
// TODO Auto-generated method stub

try {
if (address.getText().compareTo("")!=0)
{ sock = new Socket(address.getText(),13267);
System.out.println("connected to " +address.getText());
}
else
System.out.println("Pease enter your ip adresse");
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
System.out.println("Connecting...");
connec.setText("client connecting");

}

};

@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub

}

public static void main(String[] args) {
ChatTransferClient appli = new ChatTransferClient();
}



}

ll faut que tu te connecte en premier lieu ensuite tu choisis un ficher et tu envoi ( j'ai un pbleme pr la reception automatique du fichier par le client c 'st pr ça que pr le moment j ai e bouton recevoir

Utilises les balises de code (elles sont à côté des boutons gras italique et souligné)

import java.awt.BorderLayout;
import java.awt.Container;
import java.awt.Desktop;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.InetAddress;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.UnknownHostException;
import java.util.Map;

import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFileChooser;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JTextField;


public class ChatTransferServer extends JFrame implements ActionListener{

	public static String nom_fichier; //pour le chemin du fichier
  	private JTextField file_path;
    private JPanel pan= new JPanel(new GridLayout(2,1));
    private JPanel pan_connexion= new JPanel(new GridLayout(3,2));
    
    private JTextField address;
    private JLabel name_address;
	private JMenuBar fileMenuBar;
	private JMenu fileMenu;
	private JMenuItem filechoose;
	private JMenuItem fileQuit;
	private JButton btconnect = new JButton("connexion");
	private JButton btFile = new JButton("encrypt file and send");
	private JComboBox liste;
	private JTextField  connect;
	
	private Container c ;
	ByteArrayOutputStream bos = new ByteArrayOutputStream();
	public static cryptage c1 ;
	public File path;
	public String clé_serveur;
	ServerSocket servsock;
	Socket sock;
	
    /** Creates a new instance of Client */
    public ChatTransferServer() {
        super("Transfer secure file server");           
        //installation des composants graphique
        
        //pour le menu
        fileMenuBar = new JMenuBar();
		fileMenu = new JMenu("Edit");
		filechoose= new JMenuItem("Choose file");
		fileQuit = new JMenuItem("Sign out");
		

		fileMenuBar.add(fileMenu);
		fileMenu.add(filechoose);
		fileMenu.add(fileQuit);
			
		//ajout des listeners
		fileQuit.addActionListener(listenerquit);
		filechoose.addActionListener(listenerchoose);
		btFile.addActionListener(listenerbtFile);
		btconnect.addActionListener(listenerbtconnect);
		
        // sur le conteneur......
        c = getContentPane();        
    
        Object[] elements = new Object[]{"Encryption Ceasare", "Advanced Encryption Ceasare (with thumbnail)"}; 
		liste = new JComboBox(elements);
 
		name_address= new JLabel("Peer Address");
		address=new JTextField(10);
		connect= new JTextField(10);
		connect.setText("server disconnected");
		try {
			address.setText(InetAddress.getLocalHost().toString());
		} catch (UnknownHostException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
        file_path= new JTextField(15);
        file_path.setFocusable(false);
        pan_connexion.add(name_address);
        pan_connexion.add(address);
        pan_connexion.add(new JLabel(""));
        pan_connexion.add(connect);
        pan_connexion.add(new JLabel(""));
        pan_connexion.add(btconnect);
        
        pan.add(file_path);
       // pan.add(this.liste);
        pan.add(this.btFile);
        c.add(pan,BorderLayout.SOUTH);
        c.add(pan_connexion,BorderLayout.NORTH);
       
        setSize(450,200);
        setJMenuBar(fileMenuBar);
        setVisible(true);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);   
        
        
        
        
    }
    
	
    public String getcle(){
    	return clé_serveur;
    }
    
    public void setcle(String cle){
    	 this.clé_serveur=cle;
    }
    
    ActionListener listenerbtFile = new ActionListener(){
    	@Override
    	public void actionPerformed(ActionEvent act) {
    		// TODO Auto-generated method stub
    		
    		 
    			String nom=JOptionPane.showInputDialog(null,"Entrez la clé d'encryptage correspondante :","Saisie de la clé",JOptionPane.QUESTION_MESSAGE);
    			System.out.println("Server>> encryption and sending : clé "+ nom);
     	        if (file_path.getText().compareTo("")==0)
     	        	System.out.println("please select a file..");
    		
     	       
    			try
    			{

    				//envoi du nom du fichier
    				 ObjectOutputStream sortie = new ObjectOutputStream(sock.getOutputStream());
    			        
    			        // vidanger lengthtampon se sorie pour envoyer les information
    			        //d'en-tête.
    			        sortie.flush();
    				  
    				
    		        	try{
    		        		sortie.writeObject(nom_fichier);
    		        	}
    		        	catch(NullPointerException e)
    		        	{
    		        		
    		        	}
    		        	cryptage c = new cryptage(nom);
    		        	 FileInputStream inf=new FileInputStream(new File(path.getAbsolutePath()));
    		        	
    		        	
    		             ObjectOutputStream out=new ObjectOutputStream(sock.getOutputStream());  
    		             
    		                                byte buf[] = new byte[1024];
    		                                int n;                   
    		                                while((n=inf.read(buf))!=-1){
    		                                   out.write(buf,0,n);                   
    		                                }   
    		                             //  inf.close();
    		                             //  out.reset();
    		                             //  out.reset();
    		
    			      }
    				
    			catch (NullPointerException e)
    			{
    				System.out.println("Serveur not connected");
    			
    			} catch (IOException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}
    			
     	        
    			}
    		
    	};
    	
    	
    	 ActionListener listenerbtconnect = new ActionListener(){
    	    	@Override
    	    	public void actionPerformed(ActionEvent act) {
    	    		// TODO Auto-generated method stub
    	    		
					try {
						servsock = new ServerSocket(13267);
						
					} catch (IOException e) {
						// TODO Auto-generated catch block
						e.printStackTrace();
					}
  				 
					 System.out.println("Waiting...");
					 connect.setText("Waiting...");
					 
	  			      try {
						sock = servsock.accept();
					} catch (IOException e) {
						// TODO Auto-generated catch block
						e.printStackTrace();
					}
	  			      System.out.println("Accepted connection : " + sock);
	  			      connect.setText("server connected");
    	    		
    	    	}};
    	    	
    	    	

    ActionListener listenerquit = new ActionListener(){
    	@Override
    	public void actionPerformed(ActionEvent act) {
    		// TODO Auto-generated method stub
    		System.out.println(">>Exit");
    		try {
				sock.close();
			} catch (IOException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
    		System.exit(0);
    		
    	}};

    	
    	ActionListener listenerchoose = new ActionListener(){
        	@Override
        	public void actionPerformed(ActionEvent act) {
        		// TODO Auto-generated method stub
        		System.out.println(">>Choose a file");
        		System.out.println("LOG : Select a file ...");
        		file_path.setText("");
    			JFileChooser dirFileChooser = new JFileChooser();
    			
    			  
                String approve = new String("CHOOSE FILE");
                  // Le bouton pour valider l'enregistrement portera la
                 
                dirFileChooser.showDialog(dirFileChooser, approve); // Pour afficher le JFileChooser...
                    
    		        try{
    		        System.out.println( dirFileChooser.getSelectedFile().getPath());
    		        
    		        nom_fichier= dirFileChooser.getSelectedFile().getName();
    		        path=dirFileChooser.getSelectedFile();
    		      
    		        }
    		        catch(NullPointerException e)
    		        {
    		        }
    		        System.out.println("name of the file "+ nom_fichier);
    		        file_path.setText("selected file: "+ nom_fichier);
    	   
    		        try { 
    		        FileInputStream fis = new FileInputStream(dirFileChooser.getSelectedFile());
		    	    byte[] buffer = new byte[1024]; //Récupération du contenu du fichier dans une variable de type byte
		    	  //  fis.read(buffer); //Lecture du contenu de la variable buffer
		    	    
		    	  
		    	    try {
		                for (int readNum; (readNum = fis.read(buffer)) != -1;) {
		                    bos.write(buffer, 0, readNum); //no doubt here is 0
		                    //Writes len bytes from the specified byte array starting at offset off to this byte array output stream.
		                    System.out.println("read " + readNum + " bytes,");
		                }
		            } catch (IOException ex) {
		               
		            }
    		        } catch (IOException ex) {
 		               
		            }
		    
    		 
    		      
    			
    		}};

    	ActionListener listeneropen = new ActionListener(){
    		@Override
    		public void actionPerformed(ActionEvent act) {
    			// TODO Auto-generated method stub
    			System.out.println("LOG : Select a file ...");
    			JFileChooser dirFileChooser = new JFileChooser();
    			
    			

    		        if(dirFileChooser.showOpenDialog(null) == JFileChooser.APPROVE_OPTION)
    		        	dirFileChooser.getSelectedFile();
    		        System.out.println( dirFileChooser.getSelectedFile().getPath());
    		        nom_fichier= dirFileChooser.getSelectedFile().getName();
    		        System.out.println("name of the file"+ nom_fichier);
    		        
    		        //ouverture du fichier
     		       Desktop desk= Desktop.getDesktop();
     		       try {
     				desk.open(dirFileChooser.getSelectedFile());
     			} catch (IOException e) {
     				// TODO Auto-generated catch block
     				e.printStackTrace();
     			}
    		     
    		}};
    

	@Override
	public void actionPerformed(ActionEvent e) {
		// TODO Auto-generated method stub
		
	}
	
	public static void main(String[] args) {
        ChatTransferServer appli = new ChatTransferServer();
       
    }

	

}

import java.awt.BorderLayout;
import java.awt.Container;
import java.awt.Desktop;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.Socket;
import java.net.UnknownHostException;

import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFileChooser;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.filechooser.FileFilter;


public class  ChatTransferClient extends JFrame implements ActionListener{

	private static String key;
	public static String nom_fichier; //pour le chemin du fichier
  	private JTextField file_path;
    private JPanel pan= new JPanel(new GridLayout(2,1));
    private JPanel pan_connexion= new JPanel(new GridLayout(3,2));
    
    private JTextField address;
    private JLabel name_address;
	private JMenuBar fileMenuBar;
	private JMenu fileMenu;
	private JMenuItem filechoose;
	private JMenuItem fileQuit;
	private JButton btconnect = new JButton("connexion");
	private JButton btFile = new JButton("encrypt file and send");
	private JButton btreceive = new JButton("Receive");
	private JComboBox liste;
	private JTextField connec;
	private Container c ;
	
	private String path;
	ByteArrayOutputStream bos = new ByteArrayOutputStream();
	static boolean connect=false;
	static Socket sock;
	
	public static String clé_client;
    /** Creates a new instance of Client */
    public  ChatTransferClient() {
        super("Transfer secure file client");           
        //installation des composants graphique
        //pour le menu
        fileMenuBar = new JMenuBar();
		fileMenu = new JMenu("Edit");
		filechoose= new JMenuItem("Choose file");
		fileQuit = new JMenuItem("Sign out");
		

		fileMenuBar.add(fileMenu);
		fileMenu.add(filechoose);
		fileMenu.add(fileQuit);
			
		//ajout des listeners
		fileQuit.addActionListener(listenerquit);
		filechoose.addActionListener(listenerchoose);
		btconnect.addActionListener(listenerbtconnect);
		btreceive.addActionListener(listenerbtreceive);
		
        // sur le conteneur......
        c = getContentPane();        
    
        Object[] elements = new Object[]{"Encryption Ceasare", "Advanced Encryption Ceasare (with thumbnail)"}; 
		liste = new JComboBox(elements);
 

		name_address= new JLabel("Peer Address");
		address=new JTextField(10);
		connec=new JTextField(10);
        file_path= new JTextField(15);
        file_path.setFocusable(false);
        pan_connexion.add(name_address);
        pan_connexion.add(address);
        pan_connexion.add(new JLabel(""));
        pan_connexion.add(connec);
        pan_connexion.add(new JLabel(""));
        pan_connexion.add(btconnect);
		
       
        pan.add(file_path);
       // pan.add(this.liste);
        pan.add(btreceive);
        c.add(pan,BorderLayout.SOUTH);
        c.add(pan_connexion,BorderLayout.NORTH);
       
        setSize(450,200);
       // setJMenuBar(fileMenuBar);
        setVisible(true);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);     
        
        connec.setText("client disconnected");
        
       
    }
	
   
    ActionListener listenerquit = new ActionListener(){
    	@Override
    	public void actionPerformed(ActionEvent act) {
    		// TODO Auto-generated method stub
    		System.out.println(">>Exit");
    		try {
				sock.close();
			} catch (IOException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
    		System.exit(0);
    		
    	}};

    	
    	ActionListener listenerchoose = new ActionListener(){
        	@Override
        	public void actionPerformed(ActionEvent act) {
        		// TODO Auto-generated method stub
        		System.out.println(">>Choose a file");
        		System.out.println("LOG : Select a file ...");
        		file_path.setText("");
    			JFileChooser dirFileChooser = new JFileChooser();
    			

    		        if(dirFileChooser.showOpenDialog(null) == JFileChooser.APPROVE_OPTION)
    		        	dirFileChooser.getSelectedFile();
    		        try{
    		        System.out.println( dirFileChooser.getSelectedFile().getPath());
    		        nom_fichier= dirFileChooser.getSelectedFile().getName();
    		        
    		        }
    		        catch(NullPointerException e)
    		        {
    		        	
    		        }
    		        System.out.println("name of the file "+ nom_fichier);
    		        file_path.setText("selected file: "+ nom_fichier);
    		        
    	   
    		        try { 
    		        FileInputStream fis = new FileInputStream(dirFileChooser.getSelectedFile());
		    	    byte[] buffer = new byte[1024]; //Récupération du contenu du fichier dans une variable de type byte
		    	  //  fis.read(buffer); //Lecture du contenu de la variable buffer
		    	    
		    	    try {
		                for (int readNum; (readNum = fis.read(buffer)) != -1;) {
		                    bos.write(buffer, 0, readNum); //no doubt here is 0
		                    //Writes len bytes from the specified byte array starting at offset off to this byte array output stream.
		                    System.out.println("read " + readNum + " bytes,");
		                }
		            } catch (IOException ex) {
		               
		            }
    		        } catch (IOException ex) {
 		               
		            }
		    
    		 
    		      
    			
    		}};

    	
    
    		  ActionListener listenerbtreceive = new ActionListener(){
    		    	@Override
    		    	public void actionPerformed(ActionEvent act) {
    		    		// TODO Auto-generated method stub
    		    		   
    		    		
    		                   try
    		                   {
    		                   	 int filesize=6022386; // filesize temporary hardcoded

    		                   	    long start = System.currentTimeMillis();
    		                   	    int bytesRead;
    		                   	    int current = 0;
    		                   	    // localhost for testing
    		                   	   
    		                   	   
    		                   	    String nom=JOptionPane.showInputDialog(null,"Entrez la clé de decryptage correspondante :","Saisie de la clé",JOptionPane.QUESTION_MESSAGE);
    		                       
    		                   	    //recuperation name file
    		                   	 ObjectInputStream entree = new ObjectInputStream(sock.getInputStream());
    		                   	 String message= "";
    		                   	 try
    		                	{
    		                   		message = (String)entree.readObject();
    		                	}
    		                	catch (IOException e)
    		                	{
    		                		
    		                	} catch (ClassNotFoundException e) {
									// TODO Auto-generated catch block
									e.printStackTrace();
								}
    		                   	  
    		                   	  System.out.println("le fichier est "+ message);
    		                   	  file_path.setText("Receiveé file "+message);
    		                   	    // receive file
    		                   	    byte [] mybytearray  = new byte [filesize];
    		                   	    JFileChooser dirFileChooser = new JFileChooser();
    		                   	 String approve = new String("SAVE");
      		                   // Le bouton pour valider l'enregistrement portera la
      		                  
      		                    
      		                      dirFileChooser.setSelectedFile(new File (message));
    		           		       if(dirFileChooser.showDialog(dirFileChooser, approve) == JFileChooser.APPROVE_OPTION)
    		           		        	dirFileChooser.getSelectedFile();
    		           		        try{
    		           		       
    		           		        System.out.println("Server>> decryption : clé "+ nom);
    		                   	    cryptage c = new cryptage(nom);
    		                   	
    		                   	 
    		                   		ObjectInputStream in=new ObjectInputStream(sock.getInputStream());
    		                     
    		                     
    	    		             byte buf[] = new byte[1024];
    	    		             int n=0;
    	    		            
    	    		             FileOutputStream out =new FileOutputStream(new File(dirFileChooser.getSelectedFile().toString()));
    	    		            // System.out.println(dirFileChooser.getSelectedFile().toString());
    	    		             //ici pbleme
    	    		             while((n=in.read(buf))!=-1){
    	    		                 out.write(buf,0,n);                                        
    	    		             }
    	    		             
    	    		            
    	    		            // in.reset();
    	    		            // out.close();
    	    		             
    	    		            
    	    		             n=0;
    		                   	   
    		           		        }
    		           		        catch(NullPointerException e)
    		           		        {
    		           		        	
    		           		        }
    		                   }
    		           		        
    		           		        
    		           		
    		           		catch (NullPointerException e)
    		           		{
    		           			System.out.println("client not connected");
    		           		
    		           		} catch (IOException e) {
    		           			// TODO Auto-generated catch block
    		           			e.printStackTrace();
    		           		}
    		                   
    		               }
    		    		
    		    	};


    		 ActionListener listenerbtconnect = new ActionListener(){
     	    	@Override
     	    	public void actionPerformed(ActionEvent act) {
     	    		// TODO Auto-generated method stub
     	    		
     	    		 try {
     	    			 if (address.getText().compareTo("")!=0)
     	    			 { sock = new Socket(address.getText(),13267);
     	    			 		 System.out.println("connected to " +address.getText());
     	    			 }
     	    			 else
     	    				 System.out.println("Pease enter your ip adresse");
					} catch (IOException e) {
						// TODO Auto-generated catch block
						e.printStackTrace();
					}
             	    System.out.println("Connecting...");
             	    connec.setText("client connecting");
             	
     	    	}
     	    	
    		     };
   				 
	@Override
	public void actionPerformed(ActionEvent e) {
		// TODO Auto-generated method stub
		
	}
	
	public static void main(String[] args) {
        ChatTransferClient appli = new  ChatTransferClient();
      }

	

}

Tu n'aurais pas la classe cryptage tant qu'on y est ?

lol ok attends