/** {@inheritDoc} */
protected void getNewMonitors(Map<String, Monitor> map) throws MonitorException {
assert Thread.holdsLock(this);
int used = prologue.getUsed();
long modificationTime = prologue.getModificationTimeStamp();
if ((used > lastUsed) || (lastModificationTime > modificationTime)) {
lastUsed = used;
lastModificationTime = modificationTime;
Monitor monitor = getNextMonitorEntry();
while (monitor != null) {
String name = monitor.getName();
// guard against duplicate entries
if (!map.containsKey(name)) {
map.put(name, monitor);
/*
* insertedMonitors is null when called from pollFor()
* via buildMonitorMap(). Since we update insertedMonitors
* at the end of buildMonitorMap(), it's ok to skip the
* add here.
*/
if (insertedMonitors != null) {
insertedMonitors.add(monitor);
}
}
monitor = getNextMonitorEntry();
}
}
}
/** {@inheritDoc} */
public void removeHostListener(HostListener listener) {
/*
* XXX: if a disconnect method is added, make sure it calls
* this method to unregister this object from the watcher. otherwise,
* an unused MonitoredHostProvider instance may go uncollected.
*/
synchronized (listeners) {
listeners.remove(listener);
if (listeners.isEmpty() && (task != null)) {
task.cancel();
task = null;
}
}
}
/** 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);
}
}
/** {@inheritDoc} */
public void addHostListener(HostListener listener) {
synchronized (listeners) {
listeners.add(listener);
if (task == null) {
task = new NotifierTask();
timer.schedule(task, 0, interval);
}
}
}
