[
https://issues.apache.org/jira/browse/ISIS-1360?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Daniel Keir Haywood updated ISIS-1360:
--------------------------------------
Component/s: (was: Isis Persistence JDO)
(was: Isis Core)
Isis Incubator
Fix Version/s: (was: 3.0.0)
> Declarative Invariants
> ----------------------
>
> Key: ISIS-1360
> URL: https://issues.apache.org/jira/browse/ISIS-1360
> Project: Isis
> Issue Type: Proposal
> Components: Isis Incubator
> Affects Versions: 1.12.0
> Reporter: Cesar Lugo
> Priority: Minor
>
> I think that one aspect of the amplification concept Apache ISIS provides
> might be to allow some degree of declarative business rules / invariants.
> There is an interesting open source project (1) that allows a Java
> application to define declarative business rules / invariant you might want
> to fork.
>
> The difference between some other business rules engines (say RETE compliant)
> is that most business rules engines focus on conditional business rules or
> decision business rules only, and work outside the application scope, as an
> external API returning results that you must incorporate into your code with
> even more code. This one´s focus (ABL) is transactional business rules, which
> work through the persistence manager (Hibernate´s JPA in this case), so you
> don´t need to call any rules to be triggered, rules are automatically
> triggered when you persist data. Thus, it lets you use the previous values
> before saving and after saving to trigger rules (update inventory with new
> value of received quantity - old value of received quantity + old value of
> inventory).
>
> In summary, it provides:
> • Declarative rules, like:
> o InvoiceItem.amount = InvoiceItem.quantity * InvoiceItem.unitPrice * (1 +
> VAT / 100)
> o Invoice.amount = sum(InvoiceItem.amount) if InvoiceItem.status !=
> “deleted”
> o account balance = sum(invoice.amount) if status = “due
> • Automatic sequencing of the rules. This is really great, because
> instead of sequenced lines of code, you create independent rules, which you
> can maintain and change completely separate from all other rules. You can
> even have a rules manager and document each rule.
> • Automatic execution of the rules every time you do an insert, update
> or delete to any of those entity objects. Any change executes the rules
> properly. If a new rule implies altering the sequence of the execution of
> rules, this happens automatically and seamlessly.
> • Extensibility (create your own rules). Create a new weightedAverage
> () rule.
> • Documentation. You can document your rules, associate rules to topic
> or groups, like use cases where they come from.
>
>
> (1) http://www.automatedbusinesslogic.com/
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
