Hi there<br /><br />Assume we have a rule like this:<br /><br />when<br /><br /> $a : A(a==1)<br /> or<br /> ($b : B(b==1) and $c : C(c==1))<br /><br />then<br /><br /> do($a)<br /> do($b)<br /> do($c)<br /><br />end<br /><br /><br />Assuming also, that for some reason I do not want to split this rule into two.<br />Then, I get a NullPointer exception because either $a or $b and $c are not defined.<br />Is there a way to catch or check for this.<br /><br />Thanks so much for any help<br /><br />Thomas