iotjava/iotrmi/Java/IoTRMICommServer.java

   1 package iotrmi.Java;
   2
   3 import java.io.IOException;
   4 import java.nio.ByteBuffer;
   5 import java.util.Arrays;
   6 import java.util.ArrayList;
   7 import java.util.HashMap;
   8 import java.util.List;
   9 import java.util.Map;
  10 import java.util.Set;
  11 import java.lang.reflect.*;
  12
  13 import java.util.concurrent.*;
  14 import java.util.concurrent.atomic.AtomicBoolean;
  15
  16
  17 /** Class IoTRMICommServer is a class that extends IoTRMI
  18  *  <p>
  19  *  We will arbitrate packets into 2 queues and wake up the right threads/callers.
  20  *  We separate traffics one-directionally.
  21  *
  22  * @author      Rahmadi Trimananda <rtrimana @ uci.edu>
  23  * @version     1.0
  24  * @since       2017-01-27
  25  */
  26 public final class IoTRMICommServer extends IoTRMIComm {
  27
  28         /**
  29          * Class Properties
  30          */
  31         private IoTSocketServer rmiServerSend;
  32         private IoTSocketServer rmiServerRecv;
  33         private AtomicBoolean didServerSendConnect;
  34         private AtomicBoolean didServerRecvConnect;
  35
  36
  37         /**
  38          * Constructor (for skeleton)
  39          */
  40         public IoTRMICommServer(int _portSend, int _portRecv) throws
  41                 ClassNotFoundException, InstantiationException,
  42                         IllegalAccessException, IOException {
  43
  44                 super();
  45                 didServerSendConnect = new AtomicBoolean(false);
  46                 didServerRecvConnect = new AtomicBoolean(false);
  47                 rmiServerSend = new IoTSocketServer(_portSend);
  48                 rmiServerRecv = new IoTSocketServer(_portRecv);
  49                 waitForConnectionOnServerSend();
  50                 waitForConnectionOnServerRecv();
  51                 while(!didServerSendConnect.get());     // Wait until server is connected
  52                 while(!didServerRecvConnect.get()); // Wait until server is connected
  53                 waitForPacketsOnServer();
  54         }
  55
  56
  57         /**
  58          * waitForConnectionOnServerRecv() starts a thread that waits server connection
  59          */
  60         public void waitForConnectionOnServerRecv() {
  61
  62                 Thread thread = new Thread() {
  63                         public void run() {
  64                                 try {
  65                                         rmiServerRecv.connect();
  66                                         didServerRecvConnect.set(true);
  67                                 } catch (Exception ex) {
  68                                         ex.printStackTrace();
  69                                         throw new Error("IoTRMICommServer: Error starting receiver server!");
  70                                 }
  71                         }
  72                 };
  73                 thread.start();
  74         }
  75
  76
  77         /**
  78          * waitForConnectionOnServerSend() starts a thread that waits server connection
  79          */
  80         public void waitForConnectionOnServerSend() {
  81
  82                 Thread thread = new Thread() {
  83                         public void run() {
  84                                 try {
  85                                         rmiServerSend.connect();
  86                                         didServerSendConnect.set(true);
  87                                 } catch (Exception ex) {
  88                                         ex.printStackTrace();
  89                                         throw new Error("IoTRMICommServer: Error starting sender server!");
  90                                 }
  91                         }
  92                 };
  93                 thread.start();
  94         }
  95
  96
  97         /**
  98          * waitForPacketsOnServer() starts a thread that waits for packet bytes on server side
  99          */
 100         public void waitForPacketsOnServer() {
 101
 102                 Thread thread = new Thread() {
 103                         public void run() {
 104                                 byte[] packetBytes = null;
 105                                 while(true) {
 106                                         try {
 107                                                 packetBytes = rmiServerRecv.receiveBytes(packetBytes);
 108                                                 if (packetBytes != null) {
 109                                                         int packetType = IoTRMIComm.getPacketType(packetBytes);
 110                                                         if (packetType == IoTRMIUtil.METHOD_TYPE) {
 111                                                                 methodQueue.offer(packetBytes);
 112                                                         } else if (packetType == IoTRMIUtil.RET_VAL_TYPE) {
 113                                                                 returnQueue.offer(packetBytes);
 114                                                         } else
 115                                                                 throw new Error("IoTRMICommServer: Packet type is unknown: " + packetType);
 116                                                 }
 117                                                 packetBytes = null;
 118                                         } catch (Exception ex) {
 119                                                 ex.printStackTrace();
 120                                                 throw new Error("IoTRMICommServer: Error receiving return value bytes on server!");
 121                                         }
 122                                 }
 123                         }
 124                 };
 125                 thread.start();
 126         }
 127
 128
 129         /**
 130          * sendReturnObj() for non-struct objects (server side)
 131          */
 132         public synchronized void sendReturnObj(Object retObj, byte[] methodBytes) {
 133
 134                 // Send back return value
 135                 byte[] retObjBytes = null;
 136                 if (retObj != null)     // Handle nullness
 137                         retObjBytes = IoTRMIUtil.getObjectBytes(retObj);
 138                 // Send return value together with OBJECT_ID and METHOD_ID for arbitration
 139                 int objMethIdLen = IoTRMIUtil.OBJECT_ID_LEN + IoTRMIUtil.METHOD_ID_LEN;
 140                 int headerLen = objMethIdLen + IoTRMIUtil.PACKET_TYPE_LEN;
 141                 byte[] retAllBytes = null;
 142                 if (retObj == null)     // Handle nullness
 143                         retAllBytes = new byte[headerLen];
 144                 else
 145                         retAllBytes = new byte[headerLen + retObjBytes.length];
 146                 // Copy OBJECT_ID and METHOD_ID
 147                 System.arraycopy(methodBytes, 0, retAllBytes, 0, objMethIdLen);
 148                 int packetType = IoTRMIUtil.RET_VAL_TYPE;       // This is a return value
 149                 byte[] packetTypeBytes = IoTRMIUtil.intToByteArray(packetType);
 150                 System.arraycopy(packetTypeBytes, 0, retAllBytes, objMethIdLen, IoTRMIUtil.PACKET_TYPE_LEN);
 151                 // Copy array of bytes (return object)
 152                 if (retObj != null)
 153                         System.arraycopy(retObjBytes, 0, retAllBytes, headerLen, retObjBytes.length);
 154                 try {
 155                         rmiServerSend.sendBytes(retAllBytes);
 156                 } catch (IOException ex) {
 157                         ex.printStackTrace();
 158                         throw new Error("IoTRMICommServer: Error sending bytes in sendReturnObj()!");
 159                 }
 160         }
 161
 162
 163         /**
 164          * sendReturnObj() overloaded to send multiple return objects for structs (server side)
 165          */
 166         public synchronized void sendReturnObj(Class<?>[] retCls, Object[] retObj, byte[] methodBytes) {
 167
 168                 // Send back return value
 169                 byte[] retObjBytes = returnToBytes(retCls, retObj);
 170                 // Send return value together with OBJECT_ID and METHOD_ID for arbitration
 171                 int objMethIdLen = IoTRMIUtil.OBJECT_ID_LEN + IoTRMIUtil.METHOD_ID_LEN;
 172                 int headerLen = objMethIdLen + IoTRMIUtil.PACKET_TYPE_LEN;
 173                 byte[] retAllBytes = new byte[headerLen + retObjBytes.length];
 174                 // Copy OBJECT_ID and METHOD_ID
 175                 System.arraycopy(methodBytes, 0, retAllBytes, 0, objMethIdLen);
 176                 int packetType = IoTRMIUtil.RET_VAL_TYPE;       // This is a return value
 177                 byte[] packetTypeBytes = IoTRMIUtil.intToByteArray(packetType);
 178                 System.arraycopy(packetTypeBytes, 0, retAllBytes, objMethIdLen, IoTRMIUtil.PACKET_TYPE_LEN);
 179                 // Copy array of bytes (return object)
 180                 System.arraycopy(retObjBytes, 0, retAllBytes, headerLen, retObjBytes.length);
 181                 try {
 182                         rmiServerSend.sendBytes(retAllBytes);
 183                 } catch (IOException ex) {
 184                         ex.printStackTrace();
 185                         throw new Error("IoTRMICommServer: Error sending bytes in sendReturnObj()!");
 186                 }
 187         }
 188
 189
 190         /**
 191          * remoteCall() calls a method remotely by passing in parameters (server side)
 192          */
 193         public synchronized void remoteCall(int objectId, int methodId, Class<?>[] paramCls, Object[] paramObj) {
 194
 195                 // Send method info
 196                 byte[] methodBytes = methodToBytes(objectId, methodId, paramCls, paramObj);
 197                 try {
 198                         rmiServerSend.sendBytes(methodBytes);
 199                 } catch (IOException ex) {
 200                         ex.printStackTrace();
 201                         throw new Error("IoTRMICommServer: Error when sending bytes in remoteCall()!");
 202                 }
 203         }
 204 }