流口水的规则从地图中获取价值 [英] drools rule get value from a map

问题描述

如何在阻塞时获得流口水中的垂直值.

How to get the perticular value in the drools when block.

我正在寻找类似的东西，但是它不起作用:

I am looking for something like this but its not working:

我已将Hashmap插入到工作内存中，并尝试在When中检索它

I have inserted Hashmap into Working memory and trying to retrieve it in When

$expiry_date:HashMap(get("CREDIT_CARD_EXPIRATION_DATE"));
eval(ageInDays($expiry_date)>10) ;

我遇到错误

[42,37]: [ERR 101] Line 42:37 no viable alternative at input '"CREDIT_CARD_EXPIRATION_DATE"' in rule "Rule1" in pattern HashMap

推荐答案

对于地图/列表/数组，可以使用[]语法访问元素.另外，如果您使用的是Drools 5.3+，现在评估基本上是不相关的.

For maps/lists/arrays, you can use [] syntax to access elements. Also, if you are using Drools 5.3+, evals are basically irrelevant now.

rule X
when
    HashMap( ageInDays(this["CREDIT_CARD_EXPIRATION_DATE"]) > 10 )
then
    ...
end

使用Drools 5.1/5.2，您可以执行以下操作:

With Drools 5.1/5.2, you could do:

rule X
when
    HashMap( eval( ageInDays(this["CREDIT_CARD_EXPIRATION_DATE"]) > 10 ) )
then
    ...
end

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