Package one.microstream.reference

Class Lazy.Checker.Default

java.lang.Object

one.microstream.reference.Lazy.Checker.Default

All Implemented Interfaces:

Lazy.Checker, Lazy.ClearingEvaluator

Enclosing interface:

Lazy.Checker

public static final class Lazy.Checker.Default
extends Object
implements Lazy.Checker, Lazy.ClearingEvaluator

This implementation uses two dimensions to evaluate if a lazy reference will be cleared:
- time: a ref's "age" in terms of Lazy.lastTouched() compared to System.currentTimeMillis()
- memory: the amount of used memory compared to the permitted quota of total available memory.

Either dimension can be deactivated by setting its configuration value to 0.
If both are non-zero, a arithmetically combined check will make clearing of a certain reference more like the older it gets as free memory shrinks.
So, as free memory gets lower, older/passive references are cleared sooner, newer/active ones later.

Nested Class Summary

Nested classes/interfaces inherited from interface one.microstream.reference.Lazy.Checker

Lazy.Checker.Default, Lazy.Checker.Defaults

Method Summary

Modifier and Type	Method	Description
void	beginCheckCycle()
boolean	check(Lazy<?> lazyReference)
void	endCheckCycle()
static long	graceTimeMinimum()
static double	memoryQuotaNoCheck()
boolean	needsClearing(Lazy<?> lazyReference)	Returns if the given lazyReference should be cleared.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

memoryQuotaNoCheck

public static double memoryQuotaNoCheck()

graceTimeMinimum

public static long graceTimeMinimum()

beginCheckCycle

public final void beginCheckCycle()

Specified by:

beginCheckCycle in interface Lazy.Checker

endCheckCycle

public void endCheckCycle()

Specified by:

endCheckCycle in interface Lazy.Checker

check

public final boolean check(Lazy<?> lazyReference)

Specified by:

check in interface Lazy.Checker

Parameters:

lazyReference - the lazy reference to check against

Returns:

if additional checks should be prevented

needsClearing

public final boolean needsClearing(Lazy<?> lazyReference)

Description copied from interface: Lazy.ClearingEvaluator

Returns if the given lazyReference should be cleared.

Specified by:

needsClearing in interface Lazy.ClearingEvaluator

Parameters:

lazyReference - the lazy reference to evaluate

Returns:

true if the lazy reference should be cleared, false otherwise