com.espertech.esper.core.service
Interface ExpressionResultCacheService

All Known Implementing Classes:

ExpressionResultCacheServiceAgentInstance, ExpressionResultCacheServiceThreadlocal

public interface ExpressionResultCacheService

Provides 3 caches on the statement-level:

(A) On the level of indexed event properties: Properties that are wrapped in EventBean instances, such as for Enumeration Methods, get wrapped only once for the same event. The cache is keyed by property-name and EventBean reference and maintains a Collection.

(B) On the level of enumeration method: If a enumeration method expression is invoked within another enumeration method expression (not counting expression declarations), for example "source.where(a => source.minBy(b => b.x))" the "source.minBy(b => b.x)" is not dependent on any other lambda so the result gets cached. The cache is keyed by the enumeration-method-node as an IdentityHashMap and verified by a context stack (Long[]) that is built in nested evaluation calls.

(C) On the level of expression declaration: a) for non-enum evaluation and for enum-evaluation a separate cache b) The cache is keyed by the prototype-node as an IdentityHashMap and verified by a events-per-stream (EventBean[]) that is maintained or rewritten.

Method Summary

ExpressionResultCacheEntry<EventBean[],java.util.Collection<EventBean>>	getDeclaredExpressionLastColl(java.lang.Object node, EventBean[] eventsPerStream)
ExpressionResultCacheEntry<EventBean[],java.lang.Object>	getDeclaredExpressionLastValue(java.lang.Object node, EventBean[] eventsPerStream)
ExpressionResultCacheEntry<java.lang.Long[],java.lang.Object>	getEnumerationMethodLastValue(java.lang.Object node)
ExpressionResultCacheEntry<EventBean,java.util.Collection<EventBean>>	getPropertyColl(java.lang.String propertyNameFullyQualified, EventBean reference)
java.util.Deque<ExpressionResultCacheStackEntry>	getStack()
void	popContext()
boolean	popLambda()
void	pushContext(long contextNumber)
void	pushStack(ExpressionResultCacheStackEntry lambda)
void	saveDeclaredExpressionLastColl(java.lang.Object node, EventBean[] eventsPerStream, java.util.Collection<EventBean> result)
void	saveDeclaredExpressionLastValue(java.lang.Object node, EventBean[] eventsPerStream, java.lang.Object result)
void	saveEnumerationMethodLastValue(java.lang.Object node, java.lang.Object result)
void	savePropertyColl(java.lang.String propertyNameFullyQualified, EventBean reference, java.util.Collection<EventBean> events)

Method Detail

pushStack

void pushStack(ExpressionResultCacheStackEntry lambda)

popLambda

boolean popLambda()

getStack

java.util.Deque<ExpressionResultCacheStackEntry> getStack()

getPropertyColl

ExpressionResultCacheEntry<EventBean,java.util.Collection<EventBean>> getPropertyColl(java.lang.String propertyNameFullyQualified,
                                                                                      EventBean reference)

savePropertyColl

void savePropertyColl(java.lang.String propertyNameFullyQualified,
                      EventBean reference,
                      java.util.Collection<EventBean> events)

getDeclaredExpressionLastValue

ExpressionResultCacheEntry<EventBean[],java.lang.Object> getDeclaredExpressionLastValue(java.lang.Object node,
                                                                                        EventBean[] eventsPerStream)

saveDeclaredExpressionLastValue

void saveDeclaredExpressionLastValue(java.lang.Object node,
                                     EventBean[] eventsPerStream,
                                     java.lang.Object result)

getDeclaredExpressionLastColl

ExpressionResultCacheEntry<EventBean[],java.util.Collection<EventBean>> getDeclaredExpressionLastColl(java.lang.Object node,
                                                                                                      EventBean[] eventsPerStream)

saveDeclaredExpressionLastColl

void saveDeclaredExpressionLastColl(java.lang.Object node,
                                    EventBean[] eventsPerStream,
                                    java.util.Collection<EventBean> result)

getEnumerationMethodLastValue

ExpressionResultCacheEntry<java.lang.Long[],java.lang.Object> getEnumerationMethodLastValue(java.lang.Object node)

saveEnumerationMethodLastValue

void saveEnumerationMethodLastValue(java.lang.Object node,
                                    java.lang.Object result)

pushContext

void pushContext(long contextNumber)

popContext

void popContext()