src/java/iotcloud/CloudComm.java

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