Package org.drools.mvel.evaluators

Class CoincidesEvaluatorDefinition

java.lang.Object

org.drools.mvel.evaluators.CoincidesEvaluatorDefinition

All Implemented Interfaces:

Externalizable, Serializable, org.drools.compiler.rule.builder.EvaluatorDefinition, org.kie.api.runtime.rule.EvaluatorDefinition

public class CoincidesEvaluatorDefinition
extends Object
implements org.drools.compiler.rule.builder.EvaluatorDefinition

The implementation of the 'coincides' evaluator definition.

The coincides evaluator correlates two events and matches when both happen at the same time. Optionally, the evaluator accept thresholds for the distance between events' start and finish timestamps.

Lets look at an example:

$eventA : EventA( this coincides $eventB )

The previous pattern will match if and only if the start timestamps of both $eventA and $eventB are the same AND the end timestamp of both $eventA and $eventB also are the same.

Optionally, this operator accepts one or two parameters. These parameters are the thresholds for the distance between matching timestamps. If only one paratemer is given, it is used for both start and end timestamps. If two parameters are given, then the first is used as a threshold for the start timestamp and the second one is used as a threshold for the end timestamp. In other words:

 $eventA : EventA( this coincides[15s, 10s] $eventB ) 

Above pattern will match if and only if:

 abs( $eventA.startTimestamp - $eventB.startTimestamp ) <= 15s &&
 abs( $eventA.endTimestamp - $eventB.endTimestamp ) <= 10s 
 

NOTE: it makes no sense to use negative interval values for the parameters and the engine will raise an error if that happens.

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	CoincidesEvaluatorDefinition.CoincidesEvaluator	Implements the 'coincides' evaluator itself

Nested classes/interfaces inherited from interface org.drools.compiler.rule.builder.EvaluatorDefinition

org.drools.compiler.rule.builder.EvaluatorDefinition.Target

Field Summary

Fields

Modifier and Type	Field	Description
static org.drools.drl.parser.impl.Operator	COINCIDES
static org.drools.drl.parser.impl.Operator	COINCIDES_NOT
protected static String	coincidesOp

Constructor Summary

Constructors

Constructor	Description
CoincidesEvaluatorDefinition()

Method Summary

Modifier and Type	Method	Description
org.drools.core.rule.accessor.Evaluator	getEvaluator(org.drools.core.base.ValueType type, String operatorId, boolean isNegated, String parameterText)
org.drools.core.rule.accessor.Evaluator	getEvaluator(org.drools.core.base.ValueType type, String operatorId, boolean isNegated, String parameterText, org.drools.compiler.rule.builder.EvaluatorDefinition.Target left, org.drools.compiler.rule.builder.EvaluatorDefinition.Target right)
org.drools.core.rule.accessor.Evaluator	getEvaluator(org.drools.core.base.ValueType type, org.drools.drl.parser.impl.Operator operator)
org.drools.core.rule.accessor.Evaluator	getEvaluator(org.drools.core.base.ValueType type, org.drools.drl.parser.impl.Operator operator, String parameterText)
String[]	getEvaluatorIds()
org.drools.compiler.rule.builder.EvaluatorDefinition.Target	getTarget()
boolean	isNegatable()
void	readExternal(ObjectInput in)
boolean	supportsType(org.drools.core.base.ValueType type)
void	writeExternal(ObjectOutput out)

Methods inherited from class java.lang.Object

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

Field Detail

coincidesOp

protected static final String coincidesOp

COINCIDES

public static final org.drools.drl.parser.impl.Operator COINCIDES

COINCIDES_NOT

public static final org.drools.drl.parser.impl.Operator COINCIDES_NOT

Constructor Detail

CoincidesEvaluatorDefinition

public CoincidesEvaluatorDefinition()

Method Detail

readExternal

public void readExternal(ObjectInput in)
                  throws IOException,
                         ClassNotFoundException

Specified by:

readExternal in interface Externalizable

Throws:

IOException

ClassNotFoundException

writeExternal

public void writeExternal(ObjectOutput out)
                   throws IOException

Specified by:

writeExternal in interface Externalizable

Throws:

IOException

getEvaluator

public org.drools.core.rule.accessor.Evaluator getEvaluator(org.drools.core.base.ValueType type,
                                                            org.drools.drl.parser.impl.Operator operator)

Specified by:

getEvaluator in interface org.drools.compiler.rule.builder.EvaluatorDefinition

getEvaluator

public org.drools.core.rule.accessor.Evaluator getEvaluator(org.drools.core.base.ValueType type,
                                                            org.drools.drl.parser.impl.Operator operator,
                                                            String parameterText)

Specified by:

getEvaluator in interface org.drools.compiler.rule.builder.EvaluatorDefinition

getEvaluator

public org.drools.core.rule.accessor.Evaluator getEvaluator(org.drools.core.base.ValueType type,
                                                            String operatorId,
                                                            boolean isNegated,
                                                            String parameterText)

Specified by:

getEvaluator in interface org.drools.compiler.rule.builder.EvaluatorDefinition

getEvaluator

public org.drools.core.rule.accessor.Evaluator getEvaluator(org.drools.core.base.ValueType type,
                                                            String operatorId,
                                                            boolean isNegated,
                                                            String parameterText,
                                                            org.drools.compiler.rule.builder.EvaluatorDefinition.Target left,
                                                            org.drools.compiler.rule.builder.EvaluatorDefinition.Target right)

Specified by:

getEvaluator in interface org.drools.compiler.rule.builder.EvaluatorDefinition

getEvaluatorIds

public String[] getEvaluatorIds()

Specified by:

getEvaluatorIds in interface org.drools.compiler.rule.builder.EvaluatorDefinition

isNegatable

public boolean isNegatable()

Specified by:

isNegatable in interface org.drools.compiler.rule.builder.EvaluatorDefinition

getTarget

public org.drools.compiler.rule.builder.EvaluatorDefinition.Target getTarget()

Specified by:

getTarget in interface org.drools.compiler.rule.builder.EvaluatorDefinition

supportsType

public boolean supportsType(org.drools.core.base.ValueType type)

Specified by:

supportsType in interface org.drools.compiler.rule.builder.EvaluatorDefinition