After building a GEM Host in TransSECS you can register to receive the current status of the connection:

    host.addConnectionStatusListener(new ConnectionStatusListener() {
 
      @Override
      public void connectionStatusChanged(int connectionStatus, String comment) {
         System.out.println ("Current Connection Status " + connectionStatus + " Status String \"" + comment + "\"");        
      }
    });

For this code snippet to work correctly, host must not be null. This can happen if this code is run in an initialization process, such as in a StartupTrigger script, because the StartupTrigger code could be (and probably will be) run before the normal TransSECS/MIStudio startup sequence which starts the host controller. See the Thread code example below Threaded Example to solve this issue.

This code example is run from a StartupTrigger script in TransSECS (or a script triggered by the StartupTrigger in MIStudio) to set up the ConnetionStatusListener. For MIStudio, this script pushes data to two BroadcastServers (StatusListenerCommand and StatusListenerValue) whenever there is a connection status change.

 //sets up a listener to handle connection status changes
 var TransSecsController = Java.type("com.ergotech.transsecs.secs.TransSecsController");
 var ConnectionStatusListener = Java.type("com.ergotech.transsecs.secs.host.ConnectionStatusListener");
 
 
 var statusListener  = new ConnectionStatusListener() {
    connectionStatusChanged : function(connectionStatus,comment) {
      print ("Current Connection Status " + connectionStatus + " Status String \"" + comment + "\"");    
      StatusListenerComment->setStringValue(comment);
      StatusListenerValue->setIntValue(connectionStatus);    
     }
  }
 
 host=TransSecsController.findController("GEMHost");     //use  your GEM Host name 
 host.addConnectionStatusListener(statusListener);

In the code below, which is run from a StartupTrigger script in TransSECS (or a script triggered by the StartupTrigger in MIStudio), a Thread is started which waits for the host not to be null and then sets up the ConnectionStatusListener.

 //sets up a listener to handle connection status changes
 var TransSecsController = Java.type("com.ergotech.transsecs.secs.TransSecsController");
 var ConnectionStatusListener = Java.type("com.ergotech.transsecs.secs.host.ConnectionStatusListener");
 var Thread = Java.type("java.lang.Thread");
 
function waitForHost() {  
    print("wait for host THREAD started"); 
    host=TransSecsController.findController("GEMHost"); //use your host name here
    while (host==null) { 
        //print("host is still null");  
        Thread.sleep(50); //wait 50 ms
        host=TransSecsController.findController("GEMHost");
    } 
    host=TransSecsController.findController("GEMHost");
   // print("host is not null, setting up connection status listener");  
    var connectionStatusListener = new ConnectionStatusListener() {
 
    connectionStatusChanged : function (connectionStatus, comment) {
       //updateToolStatus(connectionStatus,comment);//optional, if you want to store this information somewhere
       //below is for MIStudio projects, two BroadcastServers are written to with the connection status values
      StatusListenerComment->setStringValue(comment);
      StatusListenerValue->setIntValue(connectionStatus);    
       print ("Current Connection Status " + connectionStatus + " Status String \"" + comment + "\"");        
     }
  };
   // add this listener to the host  
   host.addConnectionStatusListener(connectionStatusListener);
   print("Connection Status Trigger Registered");
 }//end of function to wait for host
 
/// START OF MAIN JAVASCRIPT CODE ///
print("Startup Trigger");
 
 var r = new java.lang.Runnable() {
     run: function() { waitForHost(); }
 }
 
 new Thread(r).start();

This is an example of setting up an “alarm listener” which will be called for any S5F1 message received by the host.

It also stores the alarm data to a table in a database.

A simple Devices setup may be something such as:

where Historical might be configured as such (as used in this example):

Use this code in the same script (e.g. StartupTrigger) where you have waited for the “host” variable to not be null (see script above). This way you will be able to add the alarm listener to the host controller during initialization phase of the interface.

//additional class imports needed by this script
 var DataSource = Java.type("com.ergotech.vib.servers.DataSource");
 var ValueChangedEvent = Java.type("com.ergotech.vib.valueobjects.ValueChangedEvent");
 var AlarmListener = Java.type("com.ergotech.transsecs.secs.host.AlarmListener");
 var StringValueObject = Java.type("com.ergotech.vib.valueobjects.StringValueObject");
 var LongValueObject = Java.type("com.ergotech.vib.valueobjects.LongValueObject"); 
 var LinkedHashMap = Java.type("java.util.LinkedHashMap");
 
 
//make sure that the "host" variable is not null by using the threaded script above to wait for the initialization to be complete
 
  //set up alarm listener 
 
 var alarmHandler  = new AlarmListener() {
    alarmReceived : function(alarmValues) {
 
        //prepare to log alarm data to the database
       id = alarmValues.getAlid();
       alcd = alarmValues.getAlcd();//alcd  plus set/cleared bit
       altx = alarmValues.getAltx();
       isSet = alarmValues.isSet(); // boolean, whether this alarm is set (true) or cleared (false)
 
       print ("alarm received -- id="+id+" altx="+altx+" alcd="+alcd+" set? "+isSet);
       DataSource.logMessage("alarm received -- id="+id+" altx="+altx+" alcd="+alcd+" set? "+isSet); 
 
 
       //make a LinkedHashMap of the alarm data so it can be saved in the database
 
       alarmDataMap = new LinkedHashMap();
       alarmDataMap.put("alid",new StringValueObject(id));
       alarmDataMap.put("altx",new StringValueObject(altx));
       alarmDataMap.put("alcd",new LongValueObject(alcd & 0x7F));  // remove the set/clear bit
       alarmDataMap.put("setorclear",new LongValueObject(isSet)); 
 
       //add this alarm data to a valueobject
       alarmData = new StringValueObject("alarm data"); //this string value will be ignored
       alarmData.setProperty("MAP",alarmDataMap); //alarmDataMap has the data to be stored
 
       //write to database
       //This assumes you have a database connection manager for your database set up in Devices called "AlarmDatabase"
       //"Historical" is the name of the TriggeredHistorical server added to "AlarmDatabase". The table name is set in this server, and the "create table" property should be set to true.
 
       /Devices/AlarmDatabase_Servers/Historical->mapTrigger(new ValueChangedEvent(this,alarmData));
 
  }
 
};
 
  host.addAlarmListener(alarmHandler);
 
  print("Alarm Listener set up and registered");

Alternate Alarm Listener using a SQL Statement rather than a Historical

//additional class imports needed by this script
 var DataSource = Java.type("com.ergotech.vib.servers.DataSource");
 var AlarmListener = Java.type("com.ergotech.transsecs.secs.host.AlarmListener");
 var ArrayValueObject = Java.type("com.ergotech.vib.valueobjects.ArrayValueObject");
 var StringValueObject = Java.type("com.ergotech.vib.valueobjects.StringValueObject");
 var LongValueObject = Java.type("com.ergotech.vib.valueobjects.LongValueObject"); 
 
 
//make sure that the "host" variable is not null by using the threaded script above to wait for the initialization to be complete
 
  //set up alarm listener 
 
 var alarmHandler  = new AlarmListener() {
    alarmReceived : function(alarmValues) {
 
        //prepare to log alarm data to the database
       id = alarmValues.getAlid();
       alcd = alarmValues.getAlcd();//alcd  plus set/cleared bit
       altx = alarmValues.getAltx();
       isSet = alarmValues.isSet(); // boolean, whether this alarm is set (true) or cleared (false)
 
       print ("alarm received -- id="+id+" altx="+altx+" alcd="+alcd+" set? "+isSet);
       DataSource.logMessage("alarm received -- id="+id+" altx="+altx+" alcd="+alcd+" set? "+isSet); 
 
 
       //make a ArrayValueObject of the alarm data so it can be saved in the database
 
       alarmData = new ArrayValueObject();
       alarmData.add(new StringValueObject(id));
       alarmData.add(new StringValueObject(altx));
       alarmData.add(new LongValueObject(alcd & 0x7F));  // remove the set/clear bit
       alarmData.add(new LongValueObject(isSet)); 
 
       //write to database
       //This assumes you have a database connection manager for your database set up in Devices called "AlarmDatabase"
       //"AlarmStore" is the name of the Database Write server added to "AlarmDatabase". 
       // the SQL statement must include ?'s for each of the parmeters in the long value object (alix, altx, alcd and isSet 
       // for example:
       // insert into SECSAlarms (alid, altx, alcd, isset) values (?,?,?,?)
 
       /Devices/AlarmDatabase_Servers/AlarmStore->setValueObject(alarmData);
 
  }
 
};
 
  host.addAlarmListener(alarmHandler);
 
  print("Alarm Listener set up and registered");