String msg = null;
Object derGauge = null;
Object trigger = null;
ObjectName object;
Comparable<?> value = null;
MonitorNotification alarm = null;
if (!isActive())
return;
// Check that neither the observed object nor the
// observed attribute are null. If the observed
// object or observed attribute is null, this means
// that the monitor started before a complete
// initialization and nothing is done.
//
synchronized (this) {
object = o.getObservedObject();
attribute = getObservedAttribute();
if (object == null || attribute == null) {
return;
}
}
// Check that the observed object is registered in the
// MBean server and that the observed attribute
// belongs to the observed object.
//
Object attributeValue = null;
try {
attributeValue = getAttribute(server, object, attribute);
if (attributeValue == null)
if (isAlreadyNotified(
o, OBSERVED_ATTRIBUTE_TYPE_ERROR_NOTIFIED))
return;
else {
notifType = OBSERVED_ATTRIBUTE_TYPE_ERROR;
setAlreadyNotified(
o, index, OBSERVED_ATTRIBUTE_TYPE_ERROR_NOTIFIED, an);
msg = "The observed attribute value is null.";
MONITOR_LOGGER.logp(Level.FINEST, Monitor.class.getName(),
"monitor", msg);
}
} catch (NullPointerException np_ex) {
if (isAlreadyNotified(o, RUNTIME_ERROR_NOTIFIED))
return;
else {
notifType = RUNTIME_ERROR;
setAlreadyNotified(o, index, RUNTIME_ERROR_NOTIFIED, an);
msg =
"The monitor must be registered in the MBean " +
"server or an MBeanServerConnection must be " +
"explicitly supplied.";
MONITOR_LOGGER.logp(Level.FINEST, Monitor.class.getName(),
"monitor", msg);
MONITOR_LOGGER.logp(Level.FINEST, Monitor.class.getName(),
"monitor", np_ex.toString());
}
} catch (InstanceNotFoundException inf_ex) {
if (isAlreadyNotified(o, OBSERVED_OBJECT_ERROR_NOTIFIED))
return;
else {
notifType = OBSERVED_OBJECT_ERROR;
setAlreadyNotified(
o, index, OBSERVED_OBJECT_ERROR_NOTIFIED, an);
msg =
"The observed object must be accessible in " +
"the MBeanServerConnection.";
MONITOR_LOGGER.logp(Level.FINEST, Monitor.class.getName(),
"monitor", msg);
MONITOR_LOGGER.logp(Level.FINEST, Monitor.class.getName(),
"monitor", inf_ex.toString());
}
} catch (AttributeNotFoundException anf_ex) {
if (isAlreadyNotified(o, OBSERVED_ATTRIBUTE_ERROR_NOTIFIED))
return;
else {
notifType = OBSERVED_ATTRIBUTE_ERROR;
setAlreadyNotified(
o, index, OBSERVED_ATTRIBUTE_ERROR_NOTIFIED, an);
msg =
"The observed attribute must be accessible in " +
"the observed object.";
MONITOR_LOGGER.logp(Level.FINEST, Monitor.class.getName(),
"monitor", msg);
MONITOR_LOGGER.logp(Level.FINEST, Monitor.class.getName(),
"monitor", anf_ex.toString());
}
} catch (MBeanException mb_ex) {
if (isAlreadyNotified(o, RUNTIME_ERROR_NOTIFIED))
return;
else {
notifType = RUNTIME_ERROR;
setAlreadyNotified(o, index, RUNTIME_ERROR_NOTIFIED, an);
msg = mb_ex.getMessage() == null ? "" : mb_ex.getMessage();
MONITOR_LOGGER.logp(Level.FINEST, Monitor.class.getName(),
"monitor", msg);
MONITOR_LOGGER.logp(Level.FINEST, Monitor.class.getName(),
"monitor", mb_ex.toString());
}
} catch (ReflectionException ref_ex) {
if (isAlreadyNotified(o, RUNTIME_ERROR_NOTIFIED)) {
return;
} else {
notifType = RUNTIME_ERROR;
setAlreadyNotified(o, index, RUNTIME_ERROR_NOTIFIED, an);
msg = ref_ex.getMessage() == null ? "" : ref_ex.getMessage();
MONITOR_LOGGER.logp(Level.FINEST, Monitor.class.getName(),
"monitor", msg);
MONITOR_LOGGER.logp(Level.FINEST, Monitor.class.getName(),
"monitor", ref_ex.toString());
}
} catch (IOException io_ex) {
if (isAlreadyNotified(o, RUNTIME_ERROR_NOTIFIED))
return;
else {
notifType = RUNTIME_ERROR;
setAlreadyNotified(o, index, RUNTIME_ERROR_NOTIFIED, an);
msg = io_ex.getMessage() == null ? "" : io_ex.getMessage();
MONITOR_LOGGER.logp(Level.FINEST, Monitor.class.getName(),
"monitor", msg);
MONITOR_LOGGER.logp(Level.FINEST, Monitor.class.getName(),
"monitor", io_ex.toString());
}
} catch (RuntimeException rt_ex) {
if (isAlreadyNotified(o, RUNTIME_ERROR_NOTIFIED))
return;
else {
notifType = RUNTIME_ERROR;
setAlreadyNotified(o, index, RUNTIME_ERROR_NOTIFIED, an);
msg = rt_ex.getMessage() == null ? "" : rt_ex.getMessage();
MONITOR_LOGGER.logp(Level.FINEST, Monitor.class.getName(),
"monitor", msg);
MONITOR_LOGGER.logp(Level.FINEST, Monitor.class.getName(),
"monitor", rt_ex.toString());
}
}
synchronized (this) {
// Check if the monitor has been stopped.
//
if (!isActive())
return;
// Check if the observed attribute has been changed.
//
// Avoid race condition where mbs.getAttribute() succeeded but
// another thread replaced the observed attribute meanwhile.
//
// Avoid setting computed derived gauge on erroneous attribute.
//
if (!attribute.equals(getObservedAttribute()))
return;
// Derive a Comparable object from the ObservedAttribute value
// if the type of the ObservedAttribute value is a complex type.
//
if (msg == null) {
try {
value = getComparableFromAttribute(object,
attribute,
attributeValue);
} catch (ClassCastException e) {
if (isAlreadyNotified(
o, OBSERVED_ATTRIBUTE_TYPE_ERROR_NOTIFIED))
return;
else {
notifType = OBSERVED_ATTRIBUTE_TYPE_ERROR;
setAlreadyNotified(o, index,
OBSERVED_ATTRIBUTE_TYPE_ERROR_NOTIFIED, an);
msg =
"The observed attribute value does not " +
"implement the Comparable interface.";
MONITOR_LOGGER.logp(Level.FINEST,
Monitor.class.getName(), "monitor", msg);
MONITOR_LOGGER.logp(Level.FINEST,
Monitor.class.getName(), "monitor", e.toString());
}
} catch (AttributeNotFoundException e) {
if (isAlreadyNotified(o, OBSERVED_ATTRIBUTE_ERROR_NOTIFIED))
return;
else {
notifType = OBSERVED_ATTRIBUTE_ERROR;
setAlreadyNotified(
o, index, OBSERVED_ATTRIBUTE_ERROR_NOTIFIED, an);
msg =
"The observed attribute must be accessible in " +
"the observed object.";
MONITOR_LOGGER.logp(Level.FINEST,
Monitor.class.getName(), "monitor", msg);
MONITOR_LOGGER.logp(Level.FINEST,
Monitor.class.getName(), "monitor", e.toString());
}
} catch (RuntimeException e) {
if (isAlreadyNotified(o, RUNTIME_ERROR_NOTIFIED))
return;
else {
notifType = RUNTIME_ERROR;
setAlreadyNotified(o, index,
RUNTIME_ERROR_NOTIFIED, an);
msg = e.getMessage() == null ? "" : e.getMessage();
MONITOR_LOGGER.logp(Level.FINEST,
Monitor.class.getName(), "monitor", msg);
MONITOR_LOGGER.logp(Level.FINEST,
Monitor.class.getName(), "monitor", e.toString());
}
}
}
// Check that the observed attribute type is supported by this
// monitor.
//
if (msg == null) {
if (!isComparableTypeValid(object, attribute, value)) {
if (isAlreadyNotified(
o, OBSERVED_ATTRIBUTE_TYPE_ERROR_NOTIFIED))
return;
else {
notifType = OBSERVED_ATTRIBUTE_TYPE_ERROR;
setAlreadyNotified(o, index,
OBSERVED_ATTRIBUTE_TYPE_ERROR_NOTIFIED, an);
msg = "The observed attribute type is not valid.";
MONITOR_LOGGER.logp(Level.FINEST,
Monitor.class.getName(), "monitor", msg);
}
}
}
// Check that threshold type is supported by this monitor.
//
if (msg == null) {
if (!isThresholdTypeValid(object, attribute, value)) {
if (isAlreadyNotified(o, THRESHOLD_ERROR_NOTIFIED))
return;
else {
notifType = THRESHOLD_ERROR;
setAlreadyNotified(o, index,
THRESHOLD_ERROR_NOTIFIED, an);
msg = "The threshold type is not valid.";
MONITOR_LOGGER.logp(Level.FINEST,
Monitor.class.getName(), "monitor", msg);
}
}
}
// Let someone subclassing the monitor to perform additional
// monitor consistency checks and report errors if necessary.
//
if (msg == null) {
msg = buildErrorNotification(object, attribute, value);
if (msg != null) {
if (isAlreadyNotified(o, RUNTIME_ERROR_NOTIFIED))
return;
else {
notifType = RUNTIME_ERROR;
setAlreadyNotified(o, index,
RUNTIME_ERROR_NOTIFIED, an);
MONITOR_LOGGER.logp(Level.FINEST,
Monitor.class.getName(), "monitor", msg);
}
}
}
// If no errors were found then clear all error flags and
// let the monitor decide if a notification must be sent.
//
if (msg == null) {
// Clear all already notified flags.
//
resetAllAlreadyNotified(o, index, an);
// Get derived gauge from comparable value.
//
derGauge = getDerivedGaugeFromComparable(object,
attribute,
value);
o.setDerivedGauge(derGauge);
o.setDerivedGaugeTimeStamp(System.currentTimeMillis());
// Check if an alarm must be fired.
//
alarm = buildAlarmNotification(object,
attribute,
(Comparable<?>) derGauge);
}
}
// Notify monitor errors
//
if (msg != null)
sendNotification(notifType,
System.currentTimeMillis(),
msg,
derGauge,
trigger,
object,
true);
// Notify monitor alarms
//
if (alarm != null && alarm.getType() != null)
sendNotification(alarm.getType(),
System.currentTimeMillis(),
alarm.getMessage(),
derGauge,
alarm.getTrigger(),
object,
false);
}