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Create Accumulate function on Drools Decision table

I am trying to create accumulate function condition on Decision table. Please help me that How to create on Decision table.

My accumulate rule function is 

when 

$i : Double(doubleValue >  1000 ) from accumulate( Product($productQty:quantity),sum($productQty))

then

System.out.println( "The quantity is exceeded more than 1000 and the total value is  " + $i );
Solution

  • You can create a column

    rows
n      condition
n+1    $i : Double() from accumulate( Product($productQty:quantity),sum($productQty))
n+2    doubleValue > $param
n+3    add quantitities and check
n+4    1000

    Two comments.

    1. This is not well-suited for decision tables unless you plan to check for different ranges of the accumulated value.
    2. Why do you use double for counting what is, most likely, integral quantities? I'd be surprise if the accumulated stock exceeds Integer.MAX_VALUE. In short: use Number in the pattern and intValue in the constraint.