CacheStats

Package: MachII.caching
Holds cache stats for a concrete strategy.

<!--- License: Copyright 2008 GreatBizTools, LLC Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. Copyright: GreatBizTools, LLC Author: Kurt Wiersma (kurt@mach-ii.com) $Id: CacheStats.cfc 1153 2008-11-14 22:10:18Z peterfarrell $ Created version: 1.6.0 Updated version: 1.6.0 Notes: Stats on a particular cache's performance may be tracked by a Mach-II provided CFC that exposes several metrics. One potential use of these metrics is to display them inside a dashboard that can be monitored while the application is running. The metrics tracked by Mach-II are as follows: * Cache hits * Cache misses * Cache active element count * Cache total element count * Cache evictions - number of elements that the cache removed to make room for new elements --->

Method Summary
public CacheStats init()

Initializes the stats.

public void decrementActiveElements([numeric amount="1"])
public void decrementCacheMisses([numeric amount="1"])
public void decrementTotalElements([numeric amount="1"])
public numeric getActiveElements()
public numeric getCacheHitRatio()

Gets the hit ratio (decimal) which is (hits / total accesses) where total accesses is hits + misses.

public numeric getCacheHits()
public numeric getCacheMisses()
public numeric getEvictions()
public struct getExtraStats()

Gets the extra stats which must be a key of this struct.

public date getStatsActiveSince()
public numeric getTotalElements()
public void incrementActiveElements([numeric amount="1"])
public void incrementCacheHits([numeric amount="1"])

Increments the number of hits by the default of 1 or by the amount passed.

public void incrementCacheMisses([numeric amount="1"])
public void incrementEvictions([numeric amount="1"])
public void incrementTotalElements([numeric amount="1"])
public void reset()

Resets all the standard caching stats.

public void setActiveElements(numeric activeElements)
public void setCacheHits(numeric cacheHits)
public void setCacheMisses(numeric cacheMisses)
public void setEvictions(numeric evictions)
public void setExtraStat(string statName, any statValue)

Sets an extra stats value by stat name.

public void setStatsActiveSince(date statsActiveSince)
public void setTotalElements(numeric totalElements)
Method Detail
decrementActiveElements

public void decrementActiveElements( [numeric amount="1"] )

Parameters:
[numeric amount="1"]

Code: 

	<cffunction name="decrementActiveElements" access="public" returntype="void" output="false">
		<cfargument name="amount" type="numeric" required="false" default="1" />
		<cfset variables.activeElements = variables.activeElements - arguments.amount />
	</cffunction>

decrementCacheMisses

public void decrementCacheMisses( [numeric amount="1"] )

Parameters:
[numeric amount="1"]

Code: 

	<cffunction name="decrementCacheMisses" access="public" returntype="void" output="false">
		<cfargument name="amount" type="numeric" required="false" default="1" />
		<cfset variables.cacheMisses = variables.cacheMisses - arguments.amount />
	</cffunction>

decrementTotalElements

public void decrementTotalElements( [numeric amount="1"] )

Parameters:
[numeric amount="1"]

Code: 

	<cffunction name="decrementTotalElements" access="public" returntype="void" output="false">
		<cfargument name="amount" type="numeric" required="false" default="1" />
		<cfset variables.totalElements = variables.totalElements - arguments.amount />
	</cffunction>

getActiveElements

public numeric getActiveElements( )

Parameters:

Code: 

	<cffunction name="getActiveElements" access="public" returntype="numeric" output="false">
		<cfreturn variables.activeElements />
	</cffunction>

getCacheHitRatio

public numeric getCacheHitRatio( )

Gets the hit ratio (decimal) which is (hits / total accesses) where total accesses is hits + misses.

Parameters:

Code: 

	<cffunction name="getCacheHitRatio" access="public" returntype="numeric" output="false"
		hint="Gets the hit ratio (decimal) which is (hits / total accesses) where total accesses is hits + misses.">
		
		<cfset var hits = getCacheHits() />
		<cfset var totalAccesses = hits + getCacheMisses() />
		
		
		<cfif hits AND totalAccesses>
			<cfreturn hits / totalAccesses />
		<cfelse>
			<cfreturn 0 />
		</cfif>
	</cffunction>

getCacheHits

public numeric getCacheHits( )

Parameters:

Code: 

	<cffunction name="getCacheHits" access="public" returntype="numeric" output="false">
		<cfreturn variables.cacheHits />
	</cffunction>

getCacheMisses

public numeric getCacheMisses( )

Parameters:

Code: 

	<cffunction name="getCacheMisses" access="public" returntype="numeric" output="false">
		<cfreturn variables.cacheMisses />
	</cffunction>

getEvictions

public numeric getEvictions( )

Parameters:

Code: 

	<cffunction name="getEvictions" access="public" returntype="numeric" output="false">
		<cfreturn variables.evictions />
	</cffunction>

getExtraStats

public struct getExtraStats( )

Gets the extra stats which must be a key of this struct.

Parameters:

Code: 

	<cffunction name="getExtraStats" access="public" returntype="struct" output="false"
		hint="Gets the extra stats which must be a key of this struct.">
		<cfreturn variables.extraStats />
	</cffunction>

getStatsActiveSince

public date getStatsActiveSince( )

Parameters:

Code: 

	<cffunction name="getStatsActiveSince" access="public" returntype="date" output="false">
		<cfreturn variables.statsActiveSince />
	</cffunction>

getTotalElements

public numeric getTotalElements( )

Parameters:

Code: 

	<cffunction name="getTotalElements" access="public" returntype="numeric" output="false">
		<cfreturn variables.totalElements />
	</cffunction>

incrementActiveElements

public void incrementActiveElements( [numeric amount="1"] )

Parameters:
[numeric amount="1"]

Code: 

	<cffunction name="incrementActiveElements" access="public" returntype="void" output="false">
		<cfargument name="amount" type="numeric" required="false" default="1" />
		<cfset variables.activeElements = variables.activeElements + arguments.amount />
	</cffunction>

incrementCacheHits

public void incrementCacheHits( [numeric amount="1"] )

Increments the number of hits by the default of 1 or by the amount passed.

Parameters:
[numeric amount="1"]

Code: 

	<cffunction name="incrementCacheHits" access="public" returntype="void" output="false"
		hint="Increments the number of hits by the default of 1 or by the amount passed.">
		<cfargument name="amount" type="numeric" required="false" default="1" />
		<cfset variables.cacheHits = variables.cacheHits + arguments.amount />
	</cffunction>

incrementCacheMisses

public void incrementCacheMisses( [numeric amount="1"] )

Parameters:
[numeric amount="1"]

Code: 

	<cffunction name="incrementCacheMisses" access="public" returntype="void" output="false">
		<cfargument name="amount" type="numeric" required="false" default="1" />
		<cfset variables.cacheMisses = variables.cacheMisses + arguments.amount />
	</cffunction>

incrementEvictions

public void incrementEvictions( [numeric amount="1"] )

Parameters:
[numeric amount="1"]

Code: 

	<cffunction name="incrementEvictions" access="public" returntype="void" output="false">
		<cfargument name="amount" type="numeric" required="false" default="1" />
		<cfset variables.evictions = variables.evictions + arguments.amount />
	</cffunction>

incrementTotalElements

public void incrementTotalElements( [numeric amount="1"] )

Parameters:
[numeric amount="1"]

Code: 

	<cffunction name="incrementTotalElements" access="public" returntype="void" output="false">
		<cfargument name="amount" type="numeric" required="false" default="1" />
		<cfset variables.totalElements = variables.totalElements + arguments.amount />
	</cffunction>

init

public CacheStats init( )

Initializes the stats.

Parameters:

Code: 

	<cffunction name="init" access="public" returntype="CacheStats" output="false"
		hint="Initializes the stats.">
		<cfreturn this />
	</cffunction>

reset

public void reset( )

Resets all the standard caching stats.

Parameters:

Code: 

	<cffunction name="reset" access="public" returntype="void" output="false"
		hint="Resets all the standard caching stats.">
		<cfset setCacheHits(0) />
		<cfset setCacheMisses(0) />
		<cfset setEvictions(0) />
		<cfset setTotalElements(0) />
		<cfset setActiveElements(0) />
		<cfset setStatsActiveSince(Now()) />
	</cffunction>

setActiveElements

public void setActiveElements( numeric activeElements )

Parameters:
numeric activeElements

Code: 

	<cffunction name="setActiveElements" access="public" returntype="void" output="false">
		<cfargument name="activeElements" type="numeric" required="true" />
		<cfset variables.activeElements = arguments.activeElements />
	</cffunction>

setCacheHits

public void setCacheHits( numeric cacheHits )

Parameters:
numeric cacheHits

Code: 

	<cffunction name="setCacheHits" access="public" returntype="void" output="false">
		<cfargument name="cacheHits" type="numeric" required="true" />
		<cfset variables.cacheHits = arguments.cacheHits />
	</cffunction>

setCacheMisses

public void setCacheMisses( numeric cacheMisses )

Parameters:
numeric cacheMisses

Code: 

	<cffunction name="setCacheMisses" access="public" returntype="void" output="false">
		<cfargument name="cacheMisses" type="numeric" required="true" />
		<cfset variables.cacheMisses = arguments.cacheMisses />
	</cffunction>

setEvictions

public void setEvictions( numeric evictions )

Parameters:
numeric evictions

Code: 

	<cffunction name="setEvictions" access="public" returntype="void" output="false">
		<cfargument name="evictions" type="numeric" required="true" />
		<cfset variables.evictions = arguments.evictions />
	</cffunction>

setExtraStat

public void setExtraStat( string statName, any statValue )

Sets an extra stats value by stat name.

Parameters:
string statName
any statValue

Code: 

	<cffunction name="setExtraStat" access="public" returntype="void" output="false"
		hint="Sets an extra stats value by stat name.">
		<cfargument name="statName" type="string" required="true" />
		<cfargument name="statValue" type="any" required="true" />
		<cfset variables.extraStats[statName] = statValue />
	</cffunction>

setStatsActiveSince

public void setStatsActiveSince( date statsActiveSince )

Parameters:
date statsActiveSince

Code: 

	<cffunction name="setStatsActiveSince" access="public" returntype="void" output="false">
		<cfargument name="statsActiveSince" type="date" required="true" />
		<cfset variables.statsActiveSince = arguments.statsActiveSince />
	</cffunction>

setTotalElements

public void setTotalElements( numeric totalElements )

Parameters:
numeric totalElements

Code: 

	<cffunction name="setTotalElements" access="public" returntype="void" output="false">
		<cfargument name="totalElements" type="numeric" required="true" />
		<cfset variables.totalElements = arguments.totalElements />
	</cffunction>