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Efficiently evaluating Drools for an item in an array or collection

Using Drools 3.0.6 (old I know), which is an efficient estimate for finding a fact in a known, fixed and fairly large array or collection (the inverse contains contains, that is, "is contained in"). Using a series of OR normal "equals" results in a StackOverflowError because the array / collection can contain several thousand entries because the evaluation of the binary Drools operator is recursive.

We have a single fact and an array of values ​​to match. The current "code" looks like this:

$f: Fact(name="TheFact", $data)
eval(!($data.equals("1") || $data.equals("2") || $data.equals("3") ... ))

for a large number of fixed values ​​(1,2,3, ...). I'm looking for something like "$ data in (1,2,3, ...)".

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Sometimes you need (or is it more readable) to put part of the evaluation in the object itself. Then you can minify the eval expressions beforeeval(!$f.isInRange(1, 200))



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