Package com.tangosol.util.filter

Interface QueryRecorderFilter<T>

All Superinterfaces:

Filter<T>, Serializable

All Known Implementing Classes:

AbstractQueryRecorderFilter, AllFilter, AlwaysFilter, AndFilter, AnyFilter, ArrayFilter, BetweenFilter, ComparisonFilter, ContainsAllFilter, ContainsAnyFilter, ContainsFilter, EqualsFilter, ExtractorFilter, GreaterEqualsFilter, GreaterFilter, InFilter, InKeySetFilter, IsNotNullFilter, IsNullFilter, LessEqualsFilter, LessFilter, LikeFilter, LimitFilter, NeverFilter, NotEqualsFilter, NotFilter, OrFilter, PredicateFilter, RegexFilter, WrapperQueryRecorderFilter, XorFilter

public interface QueryRecorderFilter<T>
extends Filter<T>

QueryRecorderFilter is an extension of EntryFilter that allows the projected or actual costs of query execution to be recorded.

During a query execution each filter performs one or more logical operations called "steps". Filters that implement this interface are expected to produce an estimated cost of execution by the explain method and the actual execution cost by the trace(QueryContext, com.tangosol.util.QueryRecord.PartialResult.TraceStep, java.util.Set) and trace(QueryContext, com.tangosol.util.QueryRecord.PartialResult.TraceStep, java.util.Map.Entry) methods.

Since:

Coherence 3.7.1

Author:

tb 2011.05.26

Method Summary

Modifier and Type	Method	Description
void	explain(QueryContext ctx, QueryRecord.PartialResult.ExplainStep step, Set setKeys)	Record the projected query execution cost by this filter.
boolean	trace(QueryContext ctx, QueryRecord.PartialResult.TraceStep step, Map.Entry entry)	Evaluate the specified entry against this filter and record the evaluation cost on the given step of the QueryRecord.
Filter	trace(QueryContext ctx, QueryRecord.PartialResult.TraceStep step, Set setKeys)	Filter the given keys using available indexes and record the cost of execution on the given step of the QueryRecord.

Methods inherited from interface com.tangosol.util.Filter

and, asLimitFilter, associatedWith, evaluate, forKeys, forPartitions, or, xor

Method Detail

explain

void explain(QueryContext ctx,
             QueryRecord.PartialResult.ExplainStep step,
             Set setKeys)

Record the projected query execution cost by this filter.

This method is expected to record the order of execution and estimated cost of applying corresponding indexes in the given step without actually applying any indexes or evaluating entries.

Parameters:

ctx - the query context

step - the step used to record the estimated execution cost

setKeys - the set of keys that would be filtered

trace

Filter trace(QueryContext ctx,
             QueryRecord.PartialResult.TraceStep step,
             Set setKeys)

Filter the given keys using available indexes and record the cost of execution on the given step of the QueryRecord.

This method should record the size of the given key set before and after applying corresponding indexes using QueryRecord.PartialResult.RecordableStep.recordPreFilterKeys(int) and QueryRecord.PartialResult.TraceStep.recordPostFilterKeys(int) as well as the corresponding execution time using the QueryRecord.PartialResult.TraceStep.recordDuration(long) method.

This method is only called if the filter is an IndexAwareFilter and its implementations should explicitly call applyIndex() to actually perform the query. Additionally, this method should return the filter object (if any) returned by the applyIndex() call.

Parameters:

ctx - the query context

step - the step used to record the execution cost

setKeys - the mutable set of keys that remain to be filtered

Returns:

the filter returned from IndexAwareFilter.applyIndex(Map, Set)

trace

boolean trace(QueryContext ctx,
              QueryRecord.PartialResult.TraceStep step,
              Map.Entry entry)

Evaluate the specified entry against this filter and record the evaluation cost on the given step of the QueryRecord.

This method should record the corresponding latencies using QueryRecord.PartialResult.TraceStep.recordDuration(long).

Implementations are responsible for explicitly calling evaluateEntry() method to perform the actual entry evaluation. Additionally, this method should return the result of the evaluateEntry call.

Parameters:

ctx - the context

step - the step used to record the evaluation cost

entry - the entry to evaluate

Returns:

the result returned from EntryFilter.evaluateEntry(Map.Entry)