com.sonicsw.mf.common.runtime
Interface IMonitoredMetrics

All Superinterfaces:

java.io.Serializable

public interface IMonitoredMetrics
extends java.io.Serializable

The IMonitoredMetrics interface represents a collection of stored metrics that are retrieved from a CollectionsMonitor instance, along with the timestamp of the last retrieved metric and a flag to indicate if there are any additional stored metrics to be retrieved from the CollectionsMonitor.

A concrete instance of IMonitoredMetrics is obtained through the invocation of a CollectionsMonitor instance's "getStoredMetrics" method. The returned IMonitoredMetrics instance will contain a set of metrics that were retrieved from the CollectionsMonitor instance's store [if there are any stored metrics], the timestamp of the last metric retrieved from the store, and a boolean flag that indicates if there are any more metrics to retrieve.

It is important to note that the "getStoredMetrics" method will return only approximately 1 MB worth of stored metrics. If the total size of the metrics stored by a given CollectionsMonitor instance, for the specified time interval, exceeds 1 MB, then a caller will have to invoke the "getStoredMetrics" method multiple times.

In order for a caller to determine if there are more stored metrics to retrieve for the specified time interval, the caller must check the appropriate flag by invoking the IMonitoredMetrics instance's "hasMoreDataToRetrieve" method.

If multiple invocations of "getStoredMetricsData" must be made in order to retrieve all of the stored metrics, then each invocation [after the initial invocation] should use an adjusted "lookback" value, based on the timestamp value returned by invoking "getLatestTimestamp". So, the pattern of execution would be: (a) initial invocation of "getStoredMetrics, passing in desired timestamp and lookback arguments (b) invoke "getMetrics" method on the returned IMonitoredMetrics instance in order to obtain retrieved metrics (c) invoke "hasMoreDataToRetrieve" method on the returned IMonitoredMetrics instance, in order to determine if a successive invocation must be made (d) if "hasMoreDataToRetrieve returns "true", invoke the "getLatestTimestamp" method of the returned IMonitoredMetrics instance and use the returned timestamp value to calculate a new "lookback" value, and use the new lookback value as an input parameter to a follow-on invocation of "getStoredMetricsData", along with the timestamp value used [as the "lastReceivedTimestamp" parameter] for the initial invocation (e) repeat steps (b) through (d), until the returned value of "hasMoreDataToRetrieve" is "false".

Invoking the "getMetrics()" method of an IMonitoredMetrics instance will return an array of IHistoricalMetric object instances. If no stored metrics were found for the specified time interval, a zero-length array will be returned from the invocation of "getMetrics".

Invoking "getLatestTimestamp()" will return the timestamp of the last metric returned from a CollectionsMonitor instance's store. If there were no stored metrics for the specified time period, the returned timestamp will correspond to the time of the invocation of "getStoredMetrics" method of the CollectionsMonitor instance. If multiple invocations of "getStoredMetrics" are required in order to obtain all of the stored metrics for the specified time period, the returned timestamp will correspond to the timestamp of the last returned metric PLUS one millisecond.

Invoking "hasMoreDataToRetrieve()" will return a boolean value that indicates whether there are more stored metrics to retrieve for the time interval specified in the invocation of "getStoredMetrics". If the returned value is "true", then successive invocations of "getStoredMetrics" will return the remaining stored metrics, and the value returned by "getLatestTimestamp()" should be used to adjust the maximum lookback value passed as an input argument for the successive invocation of "getStoredMetrics".

See Also:

MonitoredMetrics

Method Summary

long	getLatestTimestamp()
IHistoricalMetric[]	getMetrics()
boolean	hasMoreDataToRetrieve()

Method Detail

getLatestTimestamp

long getLatestTimestamp()

getMetrics

IHistoricalMetric[] getMetrics()

hasMoreDataToRetrieve

boolean hasMoreDataToRetrieve()