com.espertech.esper.common.internal.epl.historical.datacache

Class HistoricalDataCacheClearableMap

java.lang.Object

com.espertech.esper.common.internal.epl.historical.datacache.HistoricalDataCacheClearableMap

All Implemented Interfaces:

HistoricalDataCache

public class HistoricalDataCacheClearableMap
extends Object
implements HistoricalDataCache

For use in iteration over historical joins, a HistoricalDataCache implementation that serves to hold EventBean rows generated during a join evaluation involving historical streams stable for the same cache lookup keys.

Constructor Summary

Constructors

Constructor and Description
HistoricalDataCacheClearableMap() Ctor.

Method Summary

Modifier and Type	Method and Description
void	clear() Clears the cache.
void	destroy()
EventTable[]	getCached(Object methodParams) Ask the cache if the keyed value is cached, returning a list or rows if the key is in the cache, or returning null to indicate no such key cached.
boolean	isActive() Returns true if the cache is active and currently caching, or false if the cache is inactive and not currently caching
void	put(Object methodParams, EventTable[] rows) Puts into the cache a key and a list of rows, or an empty list if zero rows.

Methods inherited from class java.lang.Object

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

Constructor Detail

HistoricalDataCacheClearableMap

public HistoricalDataCacheClearableMap()

Ctor.

Method Detail

getCached

public EventTable[] getCached(Object methodParams)

Description copied from interface: HistoricalDataCache

Ask the cache if the keyed value is cached, returning a list or rows if the key is in the cache, or returning null to indicate no such key cached. Zero rows may also be cached.

Specified by:

getCached in interface HistoricalDataCache

Parameters:

methodParams - is the keys to look up in the cache

Returns:

a list of rows that can be empty is the key was found in the cache, or null if the key is not found in the cache

put

public void put(Object methodParams,
                EventTable[] rows)

Description copied from interface: HistoricalDataCache

Puts into the cache a key and a list of rows, or an empty list if zero rows.

The put method is designed to be called when the cache does not contain a key as determined by the get method. Implementations typically simply overwrite any keys put into the cache that already existed in the cache.

Specified by:

put in interface HistoricalDataCache

Parameters:

methodParams - is the keys to the cache entry

rows - is a number of rows

isActive

public boolean isActive()

Description copied from interface: HistoricalDataCache

Returns true if the cache is active and currently caching, or false if the cache is inactive and not currently caching

Specified by:

isActive in interface HistoricalDataCache

Returns:

true for caching enabled, false for no caching taking place

clear

public void clear()

Clears the cache.

destroy

public void destroy()

Specified by:

destroy in interface HistoricalDataCache