bluetoothechodemo.java

Bluetooth echo demo , to connect an server with j2se !

import javax.bluetooth.*;
import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
import javax.microedition.io.*;
import java.io.*;

/**
 * A pretty straight-forward class with menu that allows you to invoke a bluetooth server or bluetooth client
 * In keeping this demo simple the remainder the program output is shown in the console area.
 *
 */
public final class BluetoothEchoDemo extends MIDlet implements CommandListener {
  
  // Shared UUID by server and client   
  public static final UUID RFCOMM_UUID = new UUID(0x0003);	
	
  // Soft-keys
  private final Command selectCmd = new Command("Select", Command.SCREEN, 2);
  private final Command exitCmd = new Command("Exit", Command.EXIT, 1);        

  // Menu
  private static final String[] menuLabels = { "Server", "Client" };    
  private final List menu = new List("Bluetooth Echo Demo", List.IMPLICIT, menuLabels, null);

  // Classes for Server and Client
  private EchoClient echoClient;
  private EchoServer echoServer;

  public BluetoothEchoDemo() {
    menu.addCommand(exitCmd);
    menu.addCommand(selectCmd);
    menu.setCommandListener(this);
  }

  public void startApp() {
    Display.getDisplay(this).setCurrent(menu);
  }

  protected void destroyApp(boolean unconditional) {
  }

  protected void pauseApp() {
  }

  public void commandAction(Command c, Displayable d) {
    if (c == exitCmd) {
      destroyApp(true);
      notifyDestroyed();
      return;
    }

    // Instantiate the select client type
    switch (menu.getSelectedIndex()) {
      case 0:           
        echoServer = new EchoServer();
        break;
        
      case 1: 
       echoClient = new EchoClient();           
        break;
      default: // this shouldn't occur
        break;
    };
  }  

 /**
  * @abstract to assemble the data in the given stream connection
  *           probably best to move this method to a common class
  *           
  * @param Stream Connection
  * @return data read through the stream as a string
  *
  */
  public final static String readData(StreamConnection conn) {
    
    InputStream input = null;
    byte[] data = null;   
    
    try {       	      	
      input = conn.openInputStream();
      
      // Probably want to throw an exception if length is not greater then 0
      int length = input.read();       
      data= new byte[length];
      length = 0;

      // Assemble data
      while (length != data.length) {     
        int ch = input.read(data, length, data.length - length);
        if (ch == -1) {
          throw new IOException("Can't read data");
        }
        length += ch;
      }      

    } catch (IOException e) {
      System.err.println(e);
    } finally {        
    	
      // close input stream	
      if (input != null) {
        try {
          input.close();
        } catch (IOException e) {
        }
      } 
    }
    return new String(data);       
  }   
}