import Javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
import java.io.*;
import javax.microedition.io.*;
public class FileConnection extends MIDlet implements CommandListener {
private Command exit, start;
private Display display;
private Form form;
public FileConnection ()
{
display = Display.getDisplay(this);
exit = new Command("Exit", Command.EXIT, 1);
start = new Command("Start", Command.EXIT, 1);
form = new Form("Write To File");
form.addCommand(exit);
form.addCommand(start);
form.setCommandListener(this);
}
public void startApp() throws MIDletStateChangeException
{
display.setCurrent(form);
}
public void pauseApp()
{
}
public void destroyApp(boolean unconditional)
{
}
public void commandAction(Command command, Displayable displayable)
{
if (command == exit)
{
destroyApp(false);
notifyDestroyed();
}
else if (command == start)
{
try
{
OutputConnection connection = (OutputConnection)
Connector.open("file://c:/myfile.txt;append=true", Connector.WRITE );
OutputStream out = connection.openOutputStream();
PrintStream output = new PrintStream( out );
output.println( "This is a test." );
out.close();
connection.close();
Alert alert = new Alert("Completed", "Data Written", null, null);
alert.setTimeout(Alert.FOREVER);
alert.setType(AlertType.ERROR);
display.setCurrent(alert);
}
catch( ConnectionNotFoundException error )
{
Alert alert = new Alert(
"Error", "Cannot Access file.", null, null);
alert.setTimeout(Alert.FOREVER);
alert.setType(AlertType.ERROR);
display.setCurrent(alert);
}
catch( IOException error )
{
Alert alert = new Alert("Error", error.toString(), null, null);
alert.setTimeout(Alert.FOREVER);
alert.setType(AlertType.ERROR);
display.setCurrent(alert);
}
}
}
}
（出处：http://www.knowsky.com）