org.mmbase.cache
Class ReleaseStrategy

java.lang.Object
  org.mmbase.cache.ReleaseStrategy

Direct Known Subclasses:

BasicReleaseStrategy, BetterStrategy, ChainedReleaseStrategy, ConstraintsMatchingStrategy

public abstract class ReleaseStrategy

extends Object

This class is the base for all cache release strategies. You should extend this to create your own. It will contain a number of usefull utility methods to analyze query objecs and cached search results. Feel free to add those In case you miss one developing your own strategies.

Since:

MMBase-1.8

Version:

$Id: ReleaseStrategy.java,v 1.18 2006/06/28 08:10:59 nklasens Exp $

Author:

Ernst Bunders

Nested Class Summary

static class	ReleaseStrategy.StrategyResult
protected static class	ReleaseStrategy.Timer

Constructor Summary

ReleaseStrategy()

Method Summary

void	clear()
protected abstract boolean	doEvaluate(NodeEvent event, SearchQuery query, List cachedResult) implement this method to create your own strategy.
protected abstract boolean	doEvaluate(RelationEvent event, SearchQuery query, List cachedResult) implement this method to create your own strategy.
boolean	equals(Object ob)
ReleaseStrategy.StrategyResult	evaluate(NodeEvent event, SearchQuery query, List cachedResult) This method checks if evaluation should happen (active), keeps the time of the operation and updates the statistics.
ReleaseStrategy.StrategyResult	evaluate(RelationEvent event, SearchQuery query, List cachedResult)
int	getAvgEvaluationTimeInMilis()
protected static List	getConstraintsForField(String fieldName, MMObjectBuilder builder, Constraint constraint, SearchQuery query) utility for specializations: get all the constraints in the query that apply to a certain field
abstract String	getDescription()
protected static List	getFieldSteps(SearchQuery query) utility for specializations: get all the field steps of a query
abstract String	getName()
protected static List	getSortordersForField(String fieldName, MMObjectBuilder builder, List sortOrders, SearchQuery query) utility for specializations: get all the sortorders in the query that apply to a certain field
int	getTotalEvaluated()
long	getTotalEvaluationTimeMillis()
int	getTotalPreserved()
int	hashCode()
boolean	isEnabled()
void	setEnabled(boolean newStatus)
String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

ReleaseStrategy

public ReleaseStrategy()

Method Detail

getName

public abstract String getName()

getDescription

public abstract String getDescription()

getAvgEvaluationTimeInMilis

public int getAvgEvaluationTimeInMilis()

getTotalEvaluationTimeMillis

public long getTotalEvaluationTimeMillis()

evaluate

public final ReleaseStrategy.StrategyResult evaluate(NodeEvent event,
                                                     SearchQuery query,
                                                     List cachedResult)

This method checks if evaluation should happen (active), keeps the time of the operation and updates the statistics. To implement you own strategy override doEvaluate(NodeEvent event, SearchQuery query, List cachedResult).

evaluate

public final ReleaseStrategy.StrategyResult evaluate(RelationEvent event,
                                                     SearchQuery query,
                                                     List cachedResult)

getTotalPreserved

public int getTotalPreserved()

getTotalEvaluated

public int getTotalEvaluated()

doEvaluate

protected abstract boolean doEvaluate(NodeEvent event,
                                      SearchQuery query,
                                      List cachedResult)

implement this method to create your own strategy.

Parameters:

event - a node event

query -

cachedResult -

Returns:

true if the cache entry should be released

doEvaluate

protected abstract boolean doEvaluate(RelationEvent event,
                                      SearchQuery query,
                                      List cachedResult)

implement this method to create your own strategy.

Parameters:

event - a relation event

query -

cachedResult -

Returns:

true if the cache entry should be released

setEnabled

public void setEnabled(boolean newStatus)

isEnabled

public boolean isEnabled()

clear

public void clear()

equals

public boolean equals(Object ob)

hashCode

public int hashCode()

toString

public String toString()

getConstraintsForField

protected static List getConstraintsForField(String fieldName,
                                             MMObjectBuilder builder,
                                             Constraint constraint,
                                             SearchQuery query)

utility for specializations: get all the constraints in the query that apply to a certain field

Parameters:

fieldName -

builder -

constraint -

query -

getSortordersForField

protected static List getSortordersForField(String fieldName,
                                            MMObjectBuilder builder,
                                            List sortOrders,
                                            SearchQuery query)

utility for specializations: get all the sortorders in the query that apply to a certain field

Parameters:

fieldName -

builder -

sortOrders -

query -

getFieldSteps

protected static List getFieldSteps(SearchQuery query)

utility for specializations: get all the field steps of a query

Parameters:

query -