nxtOSEK/lejos_nxj/samples/BTReceive/BTReceive.java

   1 import lejos.nxt.*;
   2 import lejos.nxt.comm.*;
   3 import java.io.*;
   4
   5 /**
   6  * Receive data from another NXT, a PC, a phone,
   7  * or another bluetooth device.
   8  *
   9  * Waits for a connection, receives an int and returns
  10  * its negative as a reply, 100 times, and then closes
  11  * the connection, and waits for a new one.
  12  *
  13  * @author Lawrie Griffiths
  14  *
  15  */
  16 public class BTReceive {
  17
  18         public static void main(String [] args)  throws Exception
  19         {
  20                 String connected = "Connected";
  21         String waiting = "Waiting...";
  22         String closing = "Closing...";
  23
  24                 while (true)
  25                 {
  26                         LCD.drawString(waiting,0,0);
  27                         LCD.refresh();
  28
  29                 BTConnection btc = Bluetooth.waitForConnection();
  30
  31                         LCD.clear();
  32                         LCD.drawString(connected,0,0);
  33                         LCD.refresh();
  34
  35                         DataInputStream dis = btc.openDataInputStream();
  36                         DataOutputStream dos = btc.openDataOutputStream();
  37
  38                         for(int i=0;i<100;i++) {
  39                                 int n = dis.readInt();
  40                                 LCD.drawInt(n,7,0,1);
  41                                 LCD.refresh();
  42                                 dos.writeInt(-n);
  43                                 dos.flush();
  44                         }
  45
  46                         dis.close();
  47                         dos.close();
  48                         Thread.sleep(100); // wait for data to drain
  49                         LCD.clear();
  50                         LCD.drawString(closing,0,0);
  51                         LCD.refresh();
  52                         btc.close();
  53                         LCD.clear();
  54                 }
  55         }
  56 }
  57