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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Hello,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I am a new Drools user working my way through the examples.
To test my understanding of how the rules work, I modified the StateExampleUsingSalience.drl
file used in the </span></font><font size=2 color=black face=Arial><span
style='font-size:10.0pt;font-family:Arial;color:black;background:silver'>StateExampleWithDynamicRules</span></font><font
size=2 color=black face=Arial><span style='font-size:10.0pt;font-family:Arial;
color:black'> example</span></font><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>. The result of my change conflicted
with my understanding of how the rules should work.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I made two modifications in the StateExampleUsingSalience.drl
file. The two modifications (shown below) are the commenting out of the two
lines in the RHS portion of the “B to D” rule. My
understanding of how this would affect the result was: because the “D”
State object never changes state to “State.FINISHED” the RHS
portion of the “D to E” rule (shown below) would not execute because
the first pattern in the LHS would fail to find a State object in working
memory that met the criteria of the constraint groups defined within it.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=black face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:black'>My question is: Why does the “D
to E” rule in the </span></font><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>StateExampleDynamicRules.drl execute
the statements in the RHS portion of the rule?<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>From StateExampleUsingSalience.drl: My changes in this
file are the two lines commented out in the RHS portion.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><b><font size=2 color="#960000"
face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New";
color:#960000;font-weight:bold'>rule</span></font></b><font size=2 color=black
face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New";
color:black'> </span></font><font size=2 color=green face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New";color:green'>"B to
D"</span></font><font size=2 face="Courier New"><span style='font-size:
10.0pt;font-family:"Courier New"'><o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 color=black
face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New";
color:black'> </span></font><b><font size=2
color="#960000" face="Courier New"><span style='font-size:10.0pt;font-family:
"Courier New";color:#960000;font-weight:bold'>when</span></font></b><font
size=2 face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New"'><o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 color=black
face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New";
color:black'> State(name
== </span></font><font size=2 color=green face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New";color:green'>"B"</span></font><font
size=2 color=black face="Courier New"><span style='font-size:10.0pt;font-family:
"Courier New";color:black'>, state == State.FINISHED ) </span></font><font
size=2 face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New"'><o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 color=black
face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New";
color:black'> d
: State(name == </span></font><font size=2 color=green face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New";color:green'>"D"</span></font><font
size=2 color=black face="Courier New"><span style='font-size:10.0pt;font-family:
"Courier New";color:black'>, state == State.NOTRUN )</span></font><font size=2
face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New"'><o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 color=black
face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New";
color:black'> </span></font><b><font size=2
color="#960000" face="Courier New"><span style='font-size:10.0pt;font-family:
"Courier New";color:#960000;font-weight:bold'>then</span></font></b><font
size=2 face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New"'><o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 color=black
face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New";
color:black'> </span></font><font
size=2 color=olive face="Courier New"><span style='font-size:10.0pt;font-family:
"Courier New";color:olive'>//System.out.println(d.getName() + "
finished" );</span></font><font size=2 face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New"'><o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 color=black
face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New";
color:black'> </span></font><font
size=2 color=olive face="Courier New"><span style='font-size:10.0pt;font-family:
"Courier New";color:olive'>//d.setState( State.FINISHED );</span></font><font
size=2 face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New"'><o:p></o:p></span></font></p>
<p class=MsoNormal><b><font size=2 color="#960000" face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New";color:#960000;font-weight:
bold'>end<o:p></o:p></span></font></b></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>From StateExampleDynamicRules.drl: This is the rule
where I expected the RHS portion to NOT get executed because there aren’t
any State objects in working memory that have their name == “D” and
its state == State.FINISHED because the setState( State.FINISHED ) was never
executed on the “D” state object.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><b><font size=2 color="#960000"
face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New";
color:#960000;font-weight:bold'>rule</span></font></b><font size=2 color=black
face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New";
color:black'> </span></font><font size=2 color=green face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New";color:green'>"D to
E"</span></font><font size=2 face="Courier New"><span style='font-size:
10.0pt;font-family:"Courier New"'><o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 color=black
face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New";
color:black'> </span></font><b><font size=2
color="#960000" face="Courier New"><span style='font-size:10.0pt;font-family:
"Courier New";color:#960000;font-weight:bold'>when</span></font></b><font
size=2 face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New"'><o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 color=black
face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New";
color:black'> State(name
== </span></font><font size=2 color=green face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New";color:green'>"D"</span></font><font
size=2 color=black face="Courier New"><span style='font-size:10.0pt;font-family:
"Courier New";color:black'>, state == State.FINISHED ) </span></font><font
size=2 face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New"'><o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 color=black
face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New";
color:black'> e
: State(name == </span></font><font size=2 color=green face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New";color:green'>"E"</span></font><font
size=2 color=black face="Courier New"><span style='font-size:10.0pt;font-family:
"Courier New";color:black'>, state == State.NOTRUN )</span></font><font size=2
face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New"'><o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 color=black
face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New";
color:black'> </span></font><b><font size=2
color="#960000" face="Courier New"><span style='font-size:10.0pt;font-family:
"Courier New";color:#960000;font-weight:bold'>then</span></font></b><font
size=2 face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New"'><o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 color=black
face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New";
color:black'> System.out.println(e.getName()
+ </span></font><font size=2 color=green face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New";color:green'>"
finished"</span></font><font size=2 color=black face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New";color:black'> );</span></font><font
size=2 face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New"'><o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 color=black
face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New";
color:black'> e.setState(
State.FINISHED );</span></font><font size=2 face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New"'><o:p></o:p></span></font></p>
<p class=MsoNormal><b><font size=2 color="#960000" face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New";color:#960000;font-weight:
bold'>end<o:p></o:p></span></font></b></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=black face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:black'>After my modifications, the output was:<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=black face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:black'><o:p> </o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 color=black
face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New";
color:black'>A finished</span></font><font size=2 face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New"'><o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 color=black
face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New";
color:black'>B finished</span></font><font size=2 face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New"'><o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 color=black
face="Courier New"><span style='font-size:10.0pt;font-family:"Courier New";
color:black'>C finished</span></font><font size=2 face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New"'><o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=black face="Courier New"><span
style='font-size:10.0pt;font-family:"Courier New";color:black'>E finished<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=black face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:black'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=black face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:black'>I did not expect the “E finished”
message to be printed.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Regards,</span></font><font face=Arial><span
style='font-family:Arial'><o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Daren</span></font><font face=Arial><span style='font-family:
Arial'><o:p></o:p></span></font></p>
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