Can't get server to send file to client

Question

On the client side, when I type in a filename in the JTextField and press enter, nothing happens. I want the server to get the file and send the contents back to the client. The client is connecting; I believe my problem is in my processConnection method in the server file.
Please advise. The code for both server.java and client.java is below.
import java.io.*;
import java.net.*;
public class Server
   private BufferedWriter output;
   private BufferedReader input;
   private ServerSocket server;
   private Socket connection;
   private String message;
   public void runServer ( )
      try
         server = new ServerSocket ( 8189 );
         connection = server.accept ( );
         getStreams ( );
         processConnection ( );
         closeConnection ( );         
      catch ( EOFException eofException )
         System.out.println ( "Client terminated connection" );
      catch ( IOException ioException )
         ioException.printStackTrace ( );
   private void getStreams ( ) throws IOException
      output = new BufferedWriter ( new OutputStreamWriter ( connection.getOutputStream ( ) ) );
      output.flush ( );
      input = new BufferedReader ( new InputStreamReader ( connection.getInputStream ( ) ) );
   private void processConnection ( ) throws IOException
      message = ( String ) input.readLine ( );    
      File file = new File ( message );
      BufferedReader fileInput = new BufferedReader ( new InputStreamReader
         ( new FileInputStream ( file ) ) );
      String str = fileInput.readLine ( );
      while ( str != null )
         output.write ( str );
         str = fileInput.readLine ( );
      output.flush ( );
      fileInput.close ( );    
   private void closeConnection ( ) throws IOException
      output.close ( );
      input.close ( );
      connection.close ( );
   public static void main ( String [ ] args )
      Server application = new Server ( );
      application.runServer ( );
import java.io.*;
import java.net.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Client extends JFrame
   private JTextField enterField;     
   private JTextArea displayArea;
   private BufferedWriter output;
   private BufferedReader input;  
   private Socket connection;
   private String message;
   public Client ( )
      super ( "Client" );
      Container container = getContentPane ( );              
      enterField = new JTextField ( 10 );
      enterField.addActionListener (
         new ActionListener ( )
            public void actionPerformed ( ActionEvent event )
               sendFile ( enterField.getText ( ) );
      container.add ( enterField, BorderLayout.NORTH );
      displayArea = new JTextArea ( );
      container.add ( displayArea, BorderLayout.CENTER );
      setSize ( 500, 400 );
      setVisible ( true );
   public void runClient ( )
      try
         connectToServer ( );
         getStreams ( );
         processConnection ( );
         closeConnection ( );
      catch ( EOFException eofException )
         System.out.println ( "Server terminated connection" );
      catch ( IOException ioException )
         ioException.printStackTrace ( );
   private void connectToServer ( ) throws IOException
      displayArea.setText ( "Attempting connection\n" );
      connection = new Socket ( InetAddress.getLocalHost ( ), 8189 );
      displayArea.append ( "Connected to: " + connection.getInetAddress ( ).getHostName ( ) );
   private void getStreams ( ) throws IOException
      output = new BufferedWriter ( new OutputStreamWriter ( connection.getOutputStream ( ) ) );
      output.flush ( );
      input = new BufferedReader ( new InputStreamReader ( connection.getInputStream ( ) ) );
      displayArea.append ( "\nGot I/O streams\n" );
   private void processConnection ( ) throws IOException
      message = ( String ) input.readLine ( );
      displayArea.append ( "\n" + message );     
   private void closeConnection ( ) throws IOException
      displayArea.append ( "\nClosing connection" );
      output.close ( );
      input.close ( );
      connection.close ( );
   private void sendFile ( String message )
      try
         output.write ( message );
         output.flush ( );
      catch ( IOException ioException )
         displayArea.append ( "\nError writing string" );
   public static void main ( String [ ] args )
      Client application = new Client ( );
      application.setDefaultCloseOperation ( JFrame.EXIT_ON_CLOSE );
      application.runClient ( );

Answer 1

How about some serialization:
URLConnection con = ....
con.setRequestProperty("Content-Type", "java/octet");
con.setDoOutput(true);
ObjectOutputStream oos = new ObjectOutputStream(con.getOutputStream());
oos.writeObject(dataSend);
stream = con.getInputStream();
ObjectInputStream ois = new ObjectInputStream(stream);
Object dataReceive = ois.readObject();
You determine the types of the objects that will carry the content,
they just need to be Serializable. Maybe you will wanr to change the connection type but I think it will be almost the same scheme
HTH
Mike