Package org.drools.mvel.evaluators

Class OverlappedByEvaluatorDefinition

java.lang.Object
org.drools.mvel.evaluators.OverlappedByEvaluatorDefinition
All Implemented Interfaces:
Externalizable, Serializable, EvaluatorDefinition, EvaluatorDefinition
public class OverlappedByEvaluatorDefinition extends Object implements EvaluatorDefinition

The implementation of the overlappedby evaluator definition.

The overlappedby evaluator correlates two events and matches when the correlated event starts before the current event starts and finishes after the current event starts, but before the current event finishes. In other words, both events have an overlapping period.

Lets look at an example:

$eventA : EventA( this overlappedby $eventB )

The previous pattern will match if and only if:

 $eventB.startTimestamp < $eventA.startTimestamp < $eventB.endTimestamp < $eventA.endTimestamp

The overlappedby operator accepts 1 or 2 optional parameters as follow:

  • If one parameter is defined, this will be the maximum distance between the start timestamp of the current event and the end timestamp of the correlated event. Example:
    • $eventA : EventA( this overlappedby[ 5s ] $eventB )
    Will match if and only if: 
     
 $eventB.startTimestamp < $eventA.startTimestamp < $eventB.endTimestamp < $eventA.endTimestamp &&
 0 <= $eventB.endTimestamp - $eventA.startTimestamp <= 5s
    • If two values are defined, the first value will be the minimum distance and the second value will be the maximum distance between the start timestamp of the current event and the end timestamp of the correlated event. Example:
      • $eventA : EventA( this overlappedby[ 5s, 10s ] $eventB )
      Will match if and only if: 
       
 $eventB.startTimestamp < $eventA.startTimestamp < $eventB.endTimestamp < $eventA.endTimestamp &&
 5s <= $eventB.endTimestamp - $eventA.startTimestamp <= 10s
See Also: