iotjava/iotrmi/Java/IoTSocket.java

   1 package iotrmi.Java;
   2
   3 // Java libraries
   4 import java.io.*;
   5 import java.net.*;
   6 import java.awt.*;
   7 import java.util.*;
   8
   9
  10 /** Class IoTSocket is the basic class for IoT RMI
  11  *  socket communication. This class will be extended
  12  *  by both IoTSocketServer and IoTSocketClient
  13  *  <p>
  14  *  Adapted from Java/C++ socket implementation
  15  *  by Keith Vertanen
  16  *  @see        <a href="https://www.keithv.com/software/socket/</a>
  17  *
  18  * @author      Rahmadi Trimananda <rtrimana @ uci.edu>
  19  * @version     1.0
  20  * @since       2016-08-17
  21  */
  22 public abstract class IoTSocket {
  23
  24         /**
  25          * Class Properties
  26          */
  27         protected byte data[];
  28         protected int port;
  29         protected Socket sock;
  30         protected BufferedInputStream input;
  31         protected BufferedOutputStream output;
  32
  33         /**
  34          * Class Constant
  35          */
  36         protected static int BUFFSIZE = 128000; // how many bytes our incoming buffer can hold
  37
  38         /**
  39          * Default constructor
  40          */
  41         protected IoTSocket(int _port) throws IOException
  42         {
  43                 port = _port;
  44                 data = new byte[BUFFSIZE];
  45         }
  46
  47
  48         /**
  49          * sendBytes() sends an array of bytes
  50          */
  51         public void sendBytes(byte vals[]) throws IOException
  52         {
  53                 int len = vals.length;
  54                 output.write(len);
  55                 output.flush();
  56                 output.write(vals, 0, len);
  57                 output.flush();
  58                 receiveAck();
  59                 sendAck();
  60         }
  61
  62
  63         /**
  64          * receiveBytes() receives an array of bytes
  65          */
  66         public byte[] receiveBytes(byte val[]) throws IOException
  67         {
  68                 int i;
  69                 int totalbytes = 0;
  70                 int numbytes;
  71                 // Wait until input is available
  72                 while(input.available() == 0);
  73                 // Read the maxlen first
  74                 int maxlen = (int)input.read();
  75                 if (maxlen>BUFFSIZE)
  76                         System.out.println("IoTSocketClient/Server: Sending more bytes then will fit in buffer!");
  77                 val = new byte[maxlen];
  78                 while (totalbytes < maxlen)
  79                 {
  80                         numbytes = input.read(data);
  81                         // copy the bytes into the result buffer
  82                         for (i=totalbytes; i<totalbytes+numbytes; i++)
  83                                 val[i] = data[i-totalbytes];
  84                         totalbytes += numbytes;
  85                 }
  86                 // we now send an acknowledgement to the server to let them
  87                 // know we've got it
  88                 sendAck();
  89                 receiveAck();
  90
  91                 return val;
  92         }
  93
  94
  95         /**
  96          * Close socket connection
  97          */
  98         public void close() throws IOException
  99         {
 100                 sock.close();
 101         }
 102
 103
 104         /**
 105          * Send ACK
 106          */
 107         public void sendAck() throws IOException
 108         {
 109                 int ack;
 110                 ack = 0;
 111                 output.write(ack);
 112                 output.flush();
 113         }
 114
 115
 116         /**
 117          * Receive ACK
 118          */
 119         public void receiveAck() throws IOException
 120         {
 121                 int ack;
 122                 ack = (int) input.read();
 123         }
 124 }