Listener/JTextField to Int

[michail]

Code below

[JosAH]

Hi guy, I am doing a chat application.
I get an error. listenportext : cannot find variable

What is the exact error message and line number?

kind regards,

Jos

edit: the structure of your outer class doesn't make sense: you can't have statements at the class level, they belong in a method or constructor.

[Tolls]

You've got execution code floating around inside your class outside of a block (ie method).

[michail]

Solved problem

[Tolls]

listenportext isn't declared anywhere in that code.

[michail]

It is at the beginning!

private JTextField listenporttext;
listenportext = new JTextField("listen",6);
listenportext.addActionListener(handler);

I still can't get it to work. I have a print statement just after the Object source = event.getSource();. It recognises the action but then it does nothing.

[Tolls]

If you're going to post code then please make sure it is at least meaningful.
Those three lines, if stuck in a class, wouldn't compile.

You need to show us where you are declaring the variable, where it is initialised (less important, but you never know) and the part of the code you have a problem. With all the brackets and relevant method declarations in the right place.

[JosAH]

It is at the beginning!

private JTextField listenporttext;
listenportext = new JTextField("listen",6);
listenportext.addActionListener(handler);

I still can't get it to work. I have a print statement just after the Object source = event.getSource();. It recognises the action but then it does nothing.

That third line isn't allowed; you can't have arbitrary statements outside of a method or initialization block; please read the previous replies because it has been mentioned before (by several repliers).

kind regards,

Jos

[michail]

Ok, I will post the whole code.
Maybe I can understand it then

[michail]

This is it
The problem is, when I press listen or connect it doesn.t triger anything, so that means I can.t even test it to see if the rest of it works

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

public [B]class[/B] Server extends JFrame
{
    
    private JButton send;
    private JButton close;
    private JButton save;
    private JButton clear;
    private JButton connect;
    private JButton listen;
    private JTextArea displayarea;
    private JTextField writearea;
    private JTextField listenporttext;
    private JTextField connectport;
    private JTextField connectIp;
    public final static int CONNECTED = 1;
    public final static int WAITING = 2;
    public final static int CONNECTING = 3;
    public final static int DISCONNECTED = 4;
    public static int connectionStatus;
    private Socket connection;
    private ServerSocket server;
    private ObjectOutputStream output;
    private ObjectInputStream input;
    private ConnectionHandler connections;   
    private JTextField listenportext;
    
    [B]public[/B] Server()
{
    super("Server");

        JPanel container = new JPanel(new BorderLayout(3,3));//add to the container the components below
        //maybe put some colour
        JPanel topContainer = new JPanel(new GridLayout(2,1,2,2));
       
        JPanel topbuttonBar = new JPanel(new FlowLayout(FlowLayout.CENTER,5,5));
        JPanel inputPanel = new JPanel(new BorderLayout(5,5));
        inputPanel.setBackground(Color.RED);
        JPanel connections = new JPanel(new FlowLayout(FlowLayout.CENTER,3,3));//connections panel
        //JMenu Sth = new JMenu("sth");
        
/*Input outpout area
*/      
        listenportext = new JTextField("22222",6);
        connectport = new JTextField("22222",6);
        connectIp = new JTextField("localhost",6);
        writearea = new JTextField();
        writearea.setEditable(true);
        JTextArea displayarea = new JTextArea(30,2);
        displayarea.setLineWrap(true);
        displayarea.setEditable(false);

/*Buttons
*/
        send = new JButton("send");
        add(send);
        close = new JButton("close");
        add(close);
        save = new JButton("save");
        add(save);
        clear = new JButton("clear");
        add(clear);
        connect = new JButton("connect");
        add(connect);
        listen = new JButton("listen");
        add(listen);

        container.setBorder(BorderFactory.createLineBorder(Color.green));//compound border?
        container.add(topContainer, BorderLayout.NORTH);//add topContainer on top
        topContainer.add(connections);//add the panel with the connections buttons
        topContainer.add(topbuttonBar);//add the panel with thr rest of the buttons
        topbuttonBar.add(close);
        topbuttonBar.add(save);
        topbuttonBar.add(clear);
        topbuttonBar.add(Box.createHorizontalStrut(50));
        topbuttonBar.add(listen);
        topbuttonBar.add(listenportext);
        topbuttonBar.add(connect);
		topbuttonBar.add(connectIp);        
		topbuttonBar.add(connectport);
        container.add(inputPanel, BorderLayout.SOUTH);
        container.add(new JScrollPane(displayarea));
        inputPanel.add(writearea, BorderLayout.CENTER);
        inputPanel.add(send, BorderLayout.EAST);
        
        

/*Action Handling
*/
        ActionListener handler = new ActionsHandler();
        send.addActionListener(handler);
        close.addActionListener(handler);
        save.addActionListener(handler);
        clear.addActionListener(handler);
        connect.addActionListener(handler);
        listen.addActionListener(handler);
        writearea.addActionListener(handler);
        listenportext.addActionListener(handler);
        connectport.addActionListener(handler);
        connectIp.addActionListener(handler);

        setContentPane(container);
        pack();

        
    }

     private [B]class[/B] [B]ActionsHandler[/B] implements ActionListener
            {
                
                public void actionPerformed(ActionEvent event)
                    {
                          Object source = event.getSource();
                           
                        if (source == listen)
                        {
                            
                            String temp = listenportext.getText();
                            int port = Integer.parseInt(temp);
                            connections = new ConnectionHandler(port);
							connections.start();
                         }
                        
                        else if (source == connect)
                        {   int port;
                            String connectemp = connectport.getText();
                            
                            port = Integer.parseInt(connectemp);
                            connections = new ConnectionHandler(connectIp.getText(), port);
							connections.start();
                        }
                        
                        else if (source == close)
                        {
                            System.exit(0);
                        }

						else if (source == send || source == writearea)
						{
							if (connection !=null && connectionStatus == CONNECTED)
						{
							connections.sendData(writearea.getText());
						}
                    }
                }
                }
            
                
                
            //type object
            private [B]class[/B] [B]ConnectionHandler[/B] extends Thread
            {
                private int port;
                private String remoteip;
                private ObjectOutputStream out = null;
				private ObjectInputStream in = null;
                private ServerSocket serversocket;
                private Socket socket = null;
   //First constructor if it.s a server         
                ConnectionHandler(int port)
                {
                    Server.this.connectionStatus = WAITING;
                    this.port = port;
                    System.out.println("Waiting on port "+port);
                    //this.start();
                }
                
  //Second constructor if it.s a client          
                ConnectionHandler(String remoteip, int port)
                {
                    Server.this.connectionStatus = CONNECTING;
                    this.port = port;
                    this.remoteip = remoteip;
                    System.out.println("Connecting to "+remoteip+" "+port);
                }
                
                
                
           //thread has been started     
                public void [B]run[/B]()
                {
               
                 try
                    {
                        if (Server.this.connectionStatus == WAITING) 
                        {   
                //server waiting for a connection
							System.out.println( "Setting up server socket on port " + port );
                            serversocket = new ServerSocket(port);
							System.out.println( "Waiting for connections..." );
                            connection = serversocket.accept();
                           
                        }
                //client is connecting
                            else if (Server.this.connectionStatus == CONNECTING)
                            {
                                socket = new Socket(InetAddress.getByName(remoteip), port);
    							System.out.println("Accepted a connection from: "+InetAddress.getByName(remoteip));
    							System.out.println("Accepted a connection from: "+socket.getInetAddress());
                                
                               //while loop to handle the messages
                            }    
    						connectionEstablished();
    						while(connectionStatus == CONNECTED)
                            {
                          		String dispatch = (String)in.readObject();
                          		sendData(dispatch);
                          		
                            
                            }
 						
                        }catch (Exception e)
                            {
    						System.out.println( e );
                            }
                            finally{}
                    }
                
                
                
                private void [B]connectionEstablished[/B]() throws IOException
                {[B]//problem here
                //after connecting get the streams[/B]
                	try{
    				 out = new ObjectOutputStream(socket.getOutputStream());//auto flush
    				 out.flush();
    				 in = new ObjectInputStream(socket.getInputStream());
   						}catch(NullPointerException s){s.printStackTrace();}
   						
    				 connectionStatus = CONNECTED;
                }
                
                
                private void [B]sendData[/B](String message) 
                {
                    try {
                        
                    out.writeObject("Client>");
                    out.flush();
                    displayarea.append(message);
                        }
                        catch (IOException ioException)
                        {
                            System.out.print("Error writing");
                        }
                }
            
            }//end of connection handler
            
  
                    
        public static void [B]main[/B](String[] args) 
        {
          Server chat = new Server();
          chat.setVisible(true);
        }
  
}

[dswastik]

/*Buttons
*/
        /*JButton send = new JButton("send");
        add(send);
        JButton close = new JButton("close");
        add(close);
        JButton save = new JButton("save");
        add(save);
        JButton clear = new JButton("clear");
        add(clear);
        JButton connect = new JButton("connect");
        add(connect);
        JButton listen = new JButton("listen");
        add(listen);*/

		/*
		you have already declared the buttons as instance level variables at top
		so the listeners were not getting attached to instance level vars, rather
		to the vars declared inside the constructor
		*/
        send = new JButton("send");
		add(send);
		close = new JButton("close");
		add(close);
		save = new JButton("save");
		add(save);
		clear = new JButton("clear");
		add(clear);
		connect = new JButton("connect");
		add(connect);
		listen = new JButton("listen");
        add(listen);
/*buttons*/

[michail]

Thank you very very much. I missed that detail. Have you got any suggestions on the other methods?
Thanks again

[Tolls]

OK, so what exactly is the problem?

What is the error you are getting, stack trace and all?

[michail]

At the moment I press connect and listen, it shows the input. when I get to the run(), it doesn.t recognise the variables in the code.(serversocket). I don't know even if it distinguishes between the constants WAITING and CONNECTING in the run() method
Have I grasped the general idea? I mean am i going in the right direction with the methods ?

Thanks

[Tolls]

What do you mean by "doesn't recognise the variables".
What exception are you getting?

[michail]

Ok I got there in the end. I will post further
The problem was here---> connectionStatus == WAITING
it should have been Server.this.connectionStatus == WAITING

Thanks

[Tolls]

Eh?
connectionStatus is a static in Server, so a direct reference, or Server.connectionStatus shouldn't make a difference.

Hang on.
Do you have multiple connections coming in here? All using the single static connectionStatus?

[michail]

Hi again. I updated the code above.
I got the server running! When I try to connect I get---->>.Connecting to localhost 3333
java.net.ConnectException: Connection refused

What does that mean? Do I have to put an exception somewhere?
:confused:

[michail]

Hi, I fixed the connection problem. It was a blocked port!!
When I compile and connect to the server the server comes up with this error


java.lang.NullPointerException
at Server$ConnectionHandler.connectionEstablished(Ser ver.java:244)
at Server$ConnectionHandler.run(Server.java:222)

Any suggestions on why the OutputStream is behaving like this
It should just get the streams, right?

[JosAH]

]java.lang.NullPointerException
at Server$ConnectionHandler.connectionEstablished(Ser ver.java:244)
at Server$ConnectionHandler.run(Server.java:222)

Any suggestions on why the OutputStream is behaving like this
It should just get the streams, right?

Don't assume anything; at line 244 in your class Server.java an object is null and it shouldn't be.

kind regards,

Jos