server.java

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package datagram;

import java.io.IOException;
import javax.microedition.io.Connector;
import javax.microedition.io.Datagram;
import javax.microedition.io.DatagramConnection;
import javax.microedition.io.UDPDatagramConnection;
import javax.microedition.lcdui.Alert;
import javax.microedition.lcdui.AlertType;
import javax.microedition.lcdui.Command;
import javax.microedition.lcdui.CommandListener;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.Form;
import javax.microedition.lcdui.StringItem;
import javax.microedition.lcdui.TextField;
public class Server implements Runnable, CommandListener
{
private DatagramMIDlet parent;
private Display display;
private Form f;
private StringItem si;
private TextField tf;
private Command sendCommand = new Command("Send", Command.ITEM, 1);
Sender sender;
private String address;
public Server(DatagramMIDlet m)
{
parent = m;
display = Display.getDisplay(parent);
f = new Form("Datagram Server");
 
si = new StringItem("Status:", " ");
tf = new TextField("Send:", "", 30, TextField.ANY);
f.append(si);
f.append(tf);
f.addCommand(sendCommand);
f.setCommandListener(this);
display.setCurrent(f);
}
public void start()
{
Thread t = new Thread(this);
t.start();
}
public void run()
{
try
{
si.setText("Waiting for connection");
DatagramConnection dc
=(DatagramConnection)Connector.open("datagram://:5555");
sender = new Sender(dc);
while (true)
{
Datagram dg = dc.newDatagram(100);
dc.receive(dg);
address = dg.getAddress();
si.setText("Message received - "
+ new String(dg.getData(), 0, dg.getLength()));
}
} catch (IOException ioe)
{
Alert a = new Alert("Server", "Port 5000 is already taken.", null,
AlertType.ERROR);
a.setTimeout(Alert.FOREVER);
a.setCommandListener(this);
display.setCurrent(a);
} catch (Exception e)
{
e.printStackTrace();
}
}
public void commandAction(Command c, Displayable s)
{
if (c == sendCommand && !parent.isPaused())
{
if (address == null)
{
si.setText("No destination address");
} else
{
sender.send(address, tf.getString());
}
}
if (c == Alert.DISMISS_COMMAND)
 
{
parent.destroyApp(true);
parent.notifyDestroyed();
}
}
public void stop()
{
}
}