alma::acs::logging::MultipleRepeatGuard Class Reference

Collaboration diagram for alma::acs::logging::MultipleRepeatGuard:

Classes
class	BoundedHashMap< K, V >
Public Member Functions
	MultipleRepeatGuard (long interval, TimeUnit timeUnit, int maxRepetitions, Logic logic, int maxCacheSize)
	MultipleRepeatGuard (long interval, TimeUnit timeUnit, int maxRepetitions, Logic logic)
synchronized boolean	check (String ID)
synchronized boolean	checkAndIncrement (String ID)
synchronized void	increment (String ID)
synchronized int	counter (String ID)
synchronized int	counterAtLastExecution (String ID)
boolean	hasRepeatGuard (String ID)
RepeatGuard	getRepeatGuard (String ID)
synchronized void	setRepeatGuard (String ID, RepeatGuard guard)
int	getCacheSize ()
synchronized void	clearCache ()
void	setCacheLimit (int maxEntries)
Private Member Functions
synchronized RepeatGuard	getOrCreateRepeatGuard (String ID)
Private Attributes
final long	defaultInterval
final TimeUnit	defaultTimeUnit
final int	defaultMaxRepetitions
final Logic	defaultLogic
final BoundedHashMap< String, RepeatGuard >	guards

Detailed Description

This class can be used as a convenient map that keeps RepeatGuard objects associated with String IDs. For example, if your application repeatedly sends an event related to the unavailability of some component, and you want to limit these events on a per-component basis, then you either need to keep and use a separate RepeatGuard object for every component instance, or alternatively you can use one instance of MultipleRepeatGuard and take the component names as IDs.

The additional benefit is that this class optionally offers a bounded cache for the various RepeatGuards, which limits memory consumption for cases in which the number of possible IDs is large, e.g. if the ID is the log message coming from unknown / 3rd party source. The drawback is that the least accessed RepeatGuards will be removed internally when the cache is full and will be re-created upon access, which may distort the original guarding behavior (e.g. because the first check() of the re-created RepeatGuard always returns true, even if the old RepeatGuard object would have returned false for another 100 invocations, or because RepeatGuard::counterAtLastExecution()} will not be accurate.

Author:: hsommer

Since:: ACS 8.0.0

Constructor & Destructor Documentation

alma::acs::logging::MultipleRepeatGuard::MultipleRepeatGuard	(	long	interval,
		TimeUnit	timeUnit,
		int	maxRepetitions,
		Logic	logic,
		int	maxCacheSize
	)			`[inline]`

Constructor for a MultipleRepeatGuard with a bounded RepeatGuard cache.

The first 4 parameters are the same as in RepeatGuard#RepeatGuard(long, TimeUnit, int, Logic) and are used as defaults for all RepeatGuards created by this class. To change these values for particular RepeatGuards, use setRepeatGuard(String, RepeatGuard) using a new RepeatGuard object or the one obtained beforehand from getRepeatGuard(String).

Parameters:

	interval	Time interval (in `timeUnit` units).
	timeUnit	Time unit of `interval` parameter.
	maxRepetitions	Maximum number of repetitions.
	logic	Evaluation logic for `interval` and `maxRepetitions`. The logic will be "reduced" automatically if `interval` or `maxRepetitions` have a value <= 0, so as to be based only on the other positive value.
	maxCacheSize	Number of `ID`s (as used in ..) whose repetition we'll keep track of. Setting this value higher will use more memory; setting it lower than the actual number of IDs will result in unnecessary execution of the guarded actions, as the matching `RepeatGuard`s will be lost and re-created.

Exceptions:

IllegalArgumentException

if maxRepetitions <= 0 && interval <= 0

References defaultInterval, defaultLogic, defaultMaxRepetitions, defaultTimeUnit, and guards.

alma::acs::logging::MultipleRepeatGuard::MultipleRepeatGuard	(	long	interval,
		TimeUnit	timeUnit,
		int	maxRepetitions,
		Logic	logic
	)			`[inline]`

Constructor for a MultipleRepeatGuard without a bounded RepeatGuard cache (which means that memory limits indirectly set the bound, with possible side effects).

See also:: MultipleRepeatGuard(long, TimeUnit, int, Logic, int)

Member Function Documentation

synchronized boolean alma::acs::logging::MultipleRepeatGuard::check ( String ID ) [inline]

See also:: RepeatGuard::check()

References alma::acs::logging::RepeatGuard::check(), and getOrCreateRepeatGuard().

synchronized boolean alma::acs::logging::MultipleRepeatGuard::checkAndIncrement ( String ID ) [inline]

See also:: RepeatGuard::checkAndIncrement()

References alma::acs::logging::RepeatGuard::checkAndIncrement(), and getOrCreateRepeatGuard().

Referenced by com::cosylab::cdb::jdal::DALImpl::logRecordNotExistWithRepeatGuard().

synchronized void alma::acs::logging::MultipleRepeatGuard::clearCache ( ) [inline]

References guards.

synchronized int alma::acs::logging::MultipleRepeatGuard::counter ( String ID ) [inline]

See also:: RepeatGuard::counter()

References alma::acs::logging::RepeatGuard::counter, and getOrCreateRepeatGuard().

synchronized int alma::acs::logging::MultipleRepeatGuard::counterAtLastExecution ( String ID ) [inline]

Note that depending on the RepeatGuard cache limit, the RepeatGuard for the given ID may get re-created during this call, and thus the counter may be 0 even though the old "true" counter was > 0.

See also:: RepeatGuard::counterAtLastExecution()

References alma::acs::logging::RepeatGuard::counterAtLastExecution, and getOrCreateRepeatGuard().

Referenced by com::cosylab::cdb::jdal::DALImpl::logRecordNotExistWithRepeatGuard().

int alma::acs::logging::MultipleRepeatGuard::getCacheSize ( ) [inline]

Gets the actual number of RepeatGuards in the internal cache, regardless of whether there is an upper limit and whether it has been reached etc.

References guards.

synchronized RepeatGuard alma::acs::logging::MultipleRepeatGuard::getOrCreateRepeatGuard ( String ID ) [inline, private]

References defaultInterval, defaultLogic, defaultMaxRepetitions, defaultTimeUnit, and guards.

Referenced by check(), checkAndIncrement(), counter(), counterAtLastExecution(), getRepeatGuard(), and increment().

RepeatGuard alma::acs::logging::MultipleRepeatGuard::getRepeatGuard ( String ID ) [inline]

References getOrCreateRepeatGuard().

boolean alma::acs::logging::MultipleRepeatGuard::hasRepeatGuard ( String ID ) [inline]

References guards.

synchronized void alma::acs::logging::MultipleRepeatGuard::increment ( String ID ) [inline]

See also:: RepeatGuard::increment()

References getOrCreateRepeatGuard(), and alma::acs::logging::RepeatGuard::increment().

void alma::acs::logging::MultipleRepeatGuard::setCacheLimit ( int maxEntries ) [inline]

References guards.

synchronized void alma::acs::logging::MultipleRepeatGuard::setRepeatGuard	(	String	ID,
		RepeatGuard	guard
	)			`[inline]`

Sets a possibly modified RepeatGuard for the given ID, which allows for some RepeatGuards having different settings than those passed in MultipleRepeatGuard(long, TimeUnit, int, Logic, int).

Parameters: