src/java/iotcloud/CloudComm.java

   1 package iotcloud;
   2 import java.io.*;
   3 import java.net.*;
   4 import java.util.Arrays;
   5 import javax.crypto.*;
   6
   7 class CloudComm {
   8         String baseurl;
   9         Cipher encryptcipher;
  10         Cipher decryptcipher;
  11         Mac mac;
  12
  13         CloudComm() {
  14         }
  15
  16         CloudComm(String _baseurl, Cipher _encrypt, Cipher _decrypt, Mac _mac) {
  17                 this.baseurl=_baseurl;
  18                 this.encryptcipher = _encrypt;
  19                 this.decryptcipher = _decrypt;
  20                 this.mac = _mac;
  21         }
  22
  23         private URL buildRequest(boolean isput, long sequencenumber, long maxentries) throws IOException {
  24                 String reqstring=isput?"req=putslot":"req=getslot";
  25                 String urlstr=baseurl+"?"+reqstring+"&seq="+sequencenumber;
  26                 if (maxentries != 0)
  27                         urlstr += "&max="+maxentries;
  28                 return new URL(urlstr);
  29         }
  30
  31         public Slot[] putSlot(Slot slot, int max) {
  32                 try {
  33                         long sequencenumber=slot.getSequenceNumber();
  34                         byte[] bytes=slot.encode(mac);
  35
  36                         URL url=buildRequest(true, sequencenumber, max);
  37                         URLConnection con=url.openConnection();
  38                         HttpURLConnection http = (HttpURLConnection) con;
  39                         http.setRequestMethod("POST");
  40                         http.setFixedLengthStreamingMode(bytes.length);
  41                         http.setDoOutput(true);
  42                         http.connect();
  43                         OutputStream os=http.getOutputStream();
  44                         os.write(bytes);
  45                         System.out.println(http.getResponseMessage());
  46
  47                         InputStream is=http.getInputStream();
  48                         DataInputStream dis=new DataInputStream(is);
  49                         byte[] resptype=new byte[7];
  50                         dis.readFully(resptype);
  51                         if (Arrays.equals(resptype, "getslot".getBytes()))
  52                                 return processSlots(dis);
  53                         else if (Arrays.equals(resptype, "putslot".getBytes()))
  54                                 return null;
  55                         else
  56                                 throw new Error("Bad response to putslot");
  57                 } catch (Exception e) {
  58                         throw new Error("putSlot failed");
  59                 }
  60         }
  61
  62         public Slot[] getSlots(long sequencenumber) {
  63                 try {
  64                         URL url=buildRequest(false, sequencenumber, 0);
  65                         URLConnection con=url.openConnection();
  66                         HttpURLConnection http = (HttpURLConnection) con;
  67                         http.setRequestMethod("POST");
  68                         http.connect();
  69                         System.out.println(http.getResponseMessage());
  70                         InputStream is=http.getInputStream();
  71
  72                         DataInputStream dis=new DataInputStream(is);
  73                         byte[] resptype=new byte[7];
  74                         dis.readFully(resptype);
  75                         if (!Arrays.equals(resptype, "getslot".getBytes()))
  76                                 throw new Error("Bad Response: "+new String(resptype));
  77                         else
  78                                 return processSlots(dis);
  79                 } catch (Exception e) {
  80                         throw new Error("getSlots failed");
  81                 }
  82         }
  83
  84         Slot[] processSlots(DataInputStream dis) throws IOException {
  85                 int numberofslots=dis.readInt();
  86                 int[] sizesofslots=new int[numberofslots];
  87                 Slot[] slots=new Slot[numberofslots];
  88                 for(int i=0; i<numberofslots; i++)
  89                         sizesofslots[i]=dis.readInt();
  90
  91                 for(int i=0; i<numberofslots; i++) {
  92                         byte[] data=new byte[sizesofslots[i]];
  93                         dis.readFully(data);
  94                         slots[i]=Slot.decode(data, mac);
  95                 }
  96                 dis.close();
  97                 return slots;
  98         }
  99 }