src/main/java/at/ac/tuwien/sbc/valesriegler/xvsm/spacehelpers/SpaceListener.java

   1 package at.ac.tuwien.sbc.valesriegler.xvsm.spacehelpers;
   2
   3 import at.ac.tuwien.sbc.valesriegler.common.Util;
   4 import at.ac.tuwien.sbc.valesriegler.xvsm.AbstractXVSMConnector;
   5 import org.mozartspaces.notifications.Notification;
   6 import org.mozartspaces.notifications.NotificationListener;
   7 import org.mozartspaces.notifications.Operation;
   8 import org.slf4j.Logger;
   9 import org.slf4j.LoggerFactory;
  10
  11 import java.io.Serializable;
  12 import java.util.Date;
  13 import java.util.List;
  14 import java.util.Timer;
  15 import java.util.TimerTask;
  16
  17 /**
  18  *
  19  * The SpaceListener provides the {@link NotificationListener} interface.
  20  * <p />
  21  * In {@link SpaceListener#getEntries()} a method for reading the entities, that are normally expected from the notification,
  22  * must be supplied. Thus, it's possible in {@link SpaceListener#startHandlingAbsenceOfNotifications()} to start a timer and to
  23  * execute the actions, which are normally triggered by the notification, with space objects read from {@link SpaceListener#getEntries()}.
  24  * If {@link SpaceListener#lookAround} is true the timer periodically checks if the corresponding {@link at.ac.tuwien.sbc.valesriegler.xvsm.AbstractXVSMConnector#timeOflastOperation} is old enough (= the agent is idle for some time)
  25  * and possibly executes the action as a result.
  26  *
  27  * @author Gregor Riegler <gregor DOT riegler AT gmail DOT com>
  28  *
  29  */
  30 public abstract class SpaceListener implements NotificationListener {
  31         private static final Logger log = LoggerFactory
  32                         .getLogger(SpaceListener.class);
  33
  34         protected boolean lookAround = true;
  35         protected long timeout = 3000;
  36     protected SpaceAction spaceAction;
  37
  38         @Override
  39         public void entryOperationFinished(Notification arg0, Operation arg1,
  40                         List<? extends Serializable> entries) {
  41                 synchronized (AbstractXVSMConnector.lockObject) {
  42                         AbstractXVSMConnector.timeOflastOperation.set(new Date().getTime());
  43                         try {
  44 //                              log.info("I am running a notification now!");
  45                                 spaceAction.inNotification.set(true);
  46                                 spaceAction.onEntriesWritten(entries);
  47                         } catch (Exception e) {
  48 //                              e.printStackTrace();
  49                         }
  50
  51                 }
  52         }
  53
  54         abstract List<? extends Serializable> getEntries() throws Exception;
  55
  56         public void startHandlingAbsenceOfNotifications() {
  57                 if(!lookAround || Util.runSimulation) return;
  58                 AbstractXVSMConnector.timeOflastOperation.set(new Date().getTime() + 3500);
  59
  60                 Timer timer = new Timer();
  61
  62                 timer.schedule(new SpaceTask(), 3000, 3000);
  63         }
  64
  65         class SpaceTask extends TimerTask {
  66
  67                 @Override
  68                 public void run() {
  69                         if(new Date().getTime()-timeout <= AbstractXVSMConnector.timeOflastOperation.get()) {
  70                                 return;
  71                         }
  72                         synchronized(AbstractXVSMConnector.lockObject) {
  73                                 try {
  74                                         AbstractXVSMConnector.timeOflastOperation.set(new Date().getTime());
  75
  76                                         List<? extends Serializable> entries = getEntries();
  77                                         if(entries.size() != 0) {
  78                                                 log.info("{} entries in timer", entries.size());
  79                                                 spaceAction.inNotification.set(false);
  80                                                 spaceAction.onEntriesWritten(entries);
  81                                         } else {
  82                                         }
  83                                 } catch (Exception e) {
  84                                         log.info(e.getMessage());
  85 //                                      e.printStackTrace();
  86                                 }
  87
  88                         }
  89
  90                 }
  91         }
  92
  93 }
  94
  95
  96