public void run() {
super.run();
// save the last set of active JVMs
Set lastActiveVms = activeVms;
try {
// get the current set of active JVMs
activeVms = (HashSet) vmManager.activeVms();
} catch (MonitorException e) {
// XXX: use logging api
System.err.println("MonitoredHostProvider: polling task " + "caught MonitorException:");
e.printStackTrace();
// mark the HostManager as errored and notify listeners
setLastException(e);
fireDisconnectedEvents();
}
if (activeVms.isEmpty()) {
return;
}
Set startedVms = new HashSet();
Set terminatedVms = new HashSet();
for (Iterator i = activeVms.iterator(); i.hasNext(); /* empty */ ) {
Integer vmid = (Integer) i.next();
if (!lastActiveVms.contains(vmid)) {
// a new file has been detected, add to set
startedVms.add(vmid);
}
}
for (Iterator i = lastActiveVms.iterator(); i.hasNext();
/* empty */ ) {
Object o = i.next();
if (!activeVms.contains(o)) {
// JVM has terminated, remove it from the active list
terminatedVms.add(o);
}
}
if (!startedVms.isEmpty() || !terminatedVms.isEmpty()) {
fireVmStatusChangedEvents(activeVms, startedVms, terminatedVms);
}
}
/** Method to dump debugging information */
private void dumpAll(Map map, int lvmid) {
if (DEBUG) {
Set keys = map.keySet();
System.err.println("Dump for " + lvmid);
int j = 0;
for (Iterator i = keys.iterator(); i.hasNext(); j++) {
Monitor monitor = (Monitor) map.get(i.next());
System.err.println(j + "\t" + monitor.getName() + "=" + monitor.getValue());
}
System.err.println("nextEntry = " + nextEntry + " pollForEntry = " + pollForEntry);
System.err.println("Buffer info:");
System.err.println("buffer = " + buffer);
}
}
/** Fire hostDisconnectEvent events. */
void fireDisconnectedEvents() {
ArrayList registered = null;
HostEvent ev = null;
synchronized (listeners) {
registered = (ArrayList) listeners.clone();
}
for (Iterator i = registered.iterator(); i.hasNext(); /* empty */ ) {
HostListener l = (HostListener) i.next();
if (ev == null) {
ev = new HostEvent(this);
}
l.disconnected(ev);
}
}
/**
* Fire VmStatusChangeEvent events to HostListener objects
*
* @param active Set of Integer objects containing the local Vm Identifiers of the active JVMs
* @param started Set of Integer objects containing the local Vm Identifiers of new JVMs started
* since last interval.
* @param terminated Set of Integer objects containing the local Vm Identifiers of terminated JVMs
* since last interval.
*/
private void fireVmStatusChangedEvents(Set active, Set started, Set terminated) {
ArrayList registered = null;
VmStatusChangeEvent ev = null;
synchronized (listeners) {
registered = (ArrayList) listeners.clone();
}
for (Iterator i = registered.iterator(); i.hasNext(); /* empty */ ) {
HostListener l = (HostListener) i.next();
if (ev == null) {
ev = new VmStatusChangeEvent(this, active, started, terminated);
}
l.vmStatusChanged(ev);
}
}