So, "stringAttr" is shorthand for "getStringAttr." Okay. Next - how do I invoke other types of methods on my Java object, other than getters?
________________________________ From: Mark Proctor [mailto:[EMAIL PROTECTED] Sent: Fri 4/14/2006 1:20 PM To: user@drools.codehaus.org Subject: Re: [drools-user] The DRL notation vs. jbossrules Rule Language - ? Dmitry Goldenberg wrote: > rule "First Rule" > when > ClassA( stringAttr == "xyz" ) > ClassB( intAttr > 50 ) > then > // do some java code > end > > In this example, where is the call made to the getStringAttr() and > getIntAttr() methods on instances of ClassA and ClassB ?? > look at LiteralConstraint and the ASM code, we take car of this for you. We believe this syntax to be less verbose and more declarative and clearer than standard java notation. It is also directly from JRules. This should make it more trivial for JRules developers to directly convert their code. > > rule "First Rule" > when > objA : ClassA( stringAttr == "xyz" ) > objB : ClassB( intAttr > 50 ) > then > // do some java code > System.out.println(objA); > System.out.println(objB); > end > > Here, are objA and objB Boolean ? > > > No here objA is a reference to an instance of ClassA and objB is a reference to an instance of ClassB. > ________________________________ > > From: Edson Tirelli [mailto:[EMAIL PROTECTED] > Sent: Thu 4/13/2006 3:47 PM > To: user@drools.codehaus.org > Subject: Re: [drools-user] The DRL notation vs. jbossrules Rule Language - ? > > > > All, > > Find in the following link, the documentation that is being built > for drools 3. > > http://labs.jboss.com/portal/jbossrules/docs > > On a quick explanation, the new syntax would be: > > ------------ > rule "name" > ATTRIBUTES > when > LHS > then > RHS > end > ------------ > > ATTRIBUTES: those are rule attributes like salience, duration, etc, in a > similar way Drools 2.x uses. > > LHS: this is the left hand side of the rule. This is the previous > "parameter" + "condition" statements. (see bellow) > > RHS: this is the right hand side of the rule. This is the consequence, > the same way in drools 2. > > I think the simple way to explain LHS is to make a conversion example: > > > <rule name="First Rule"> > > <parameter identifier="objA"> > <class>ClassA</class> > </parameter> > > <parameter identifier="objB"> > <class>ClassB</class> > </parameter> > > <java:condition> objA.getStringAttr().equals("xyz") </java:condition> > <java:condition> objB.getIntAttr() > 50 </java:condition> > > <java:consequence> > // some java code > </java:consequence> > > </rule> > > The above rule when converted to Drools 3 would became: > > rule "First Rule" > when > ClassA( stringAttr == "xyz" ) > ClassB( intAttr > 50 ) > then > // do some java code > end > > If you need a reference to the actual object matched in each "column" > (more or less what Drools 2 call parameter), you can bind it in the > following way: > > rule "First Rule" > when > objA : ClassA( stringAttr == "xyz" ) > objB : ClassB( intAttr > 50 ) > then > // do some java code > System.out.println(objA); > System.out.println(objB); > end > > In the documentation you will find syntax diagrams that can help you > understand all possible syntaxes and all the new operators/features > drools 3 has. > > []s > Edson > > > Ronald van Kuijk wrote: > > >> AINAE, but it could be as simple as 'replacing' condition with when and >> consequence with then, but I'll let the experts tell me. >> >> Ronald >> >> 2006/4/13, Dmitry Goldenberg <[EMAIL PROTECTED]>: >> >> >> >>> I don't understand the relationship between the XML-based DRL notation and >>> this new lingo with "when" / "then". >>> >>> With the DRL notation, my understanding is that you write an XML structure >>> like the one I'm including below. How does this change with the when/then >>> notation? Thanks. >>> >>> >>> <?xml version="1.0"?> >>> >>> <rule-set name="SamplePolicyRuleSet" >>> >>> xmlns="http://drools.org/rules"; >>> >>> xmlns:java="http://drools.org/semantics/java"; >>> >>> xmlns:xs="http://www.w3.org/2001/XMLSchema-instance"; >>> >>> xs:schemaLocation="http://drools.org/rules rules.xsd >>> http://drools.org/semantics/java java.xsd"> >>> >>> >>> >>> <!-- Imports --> >>> >>> <java:import>java.lang.Object</java:import> >>> >>> <java:import>java.lang.String</java:import> >>> >>> <!-- Utility functions --> >>> >>> <java:functions> >>> >>> public boolean f1(com.weblayers.platform.rule.PolicyExecContextcontext) >>> >>> { >>> >>> return ...; >>> >>> } >>> >>> public boolean f2(com.weblayers.platform.rule.PolicyExecContextcontext) >>> >>> { >>> >>> return ...; >>> >>> } >>> >>> </java:functions> >>> >>> >>> >>> <!-First Rule: IF (P1 AND P2) THEN RETURN OK --> >>> >>> <rule name="First Rule"> >>> >>> <!-- Rule parameters --> >>> >>> <parameter identifier="context"> >>> >>> <class>MyContext</class> >>> >>> </parameter> >>> >>> >>> >>> <!-- Rule Conditions --> >>> >>> <java:condition> >>> >>> f1() && f2() >>> >>> </java:condition> >>> >>> >>> >>> <!-- Rule Consequences --> >>> >>> <java:consequence> >>> >>> context.setReturn(Constants.OK); >>> >>> </java:consequence> >>> >>> </rule> >>> >>> >>> >>> <!-Second Rule: IF (!(P1 AND P2)) THEN RETURN FAILURE --> >>> >>> <rule name="Second Rule"> >>> >>> <!-- Rule parameters --> >>> >>> <parameter identifier="context"> >>> >>> <class>MyContext</class> >>> >>> </parameter> >>> >>> >>> >>> <!-- Rule Conditions --> >>> >>> <java:condition> >>> >>> !(f1() && f2()) >>> >>> </java:condition> >>> >>> >>> >>> <!-- Rule Consequences --> >>> >>> <java:consequence> >>> >>> context.setVerdict(Constants.FAIL); >>> >>> </java:consequence> >>> >>> </rule> >>> >>> >>> >>> </rule-set> >>> >>> >>> >>> >>> >>> >>> >>> >> >> > > > -- > --- > Edson Tirelli > Auster Solutions do Brasil > @ www.auster.com.br > +55 11 5096-2277 / +55 11 9218-4151 > > > > >
