Re: [rules-users] NullPointerException with Wrapper objects
All conditions of all applicable rules are evaluated when you insert an object into
working memory. This decides which rule actions can go on the agenda. Only when a rule
action is on the agenda is the salience used to determine the order of action firing. So
doing the null check in the way you're doing it will not work.
You must put the null check in the same rule, before the potentially null property is
used.
rule "Nett Salary" salience 70
when
Salary ( loanDeduction != null, nett != ( gross – loanDeduction – pf) )
then
log("Invalid nett salary amount");
end
--- On Wed, 5/13/09, dhai <sdhari(a)hotmail.com> wrote:
From: dhai <sdhari(a)hotmail.com>
Subject: [rules-users] NullPointerException with Wrapper objects
To: rules-users(a)lists.jboss.org
Date: Wednesday, May 13, 2009, 12:14 AM
I am facing problems which many have encountered in the
past. I searched
forums but could not get precise answer. The problem is
with null values in
Wrapper objects. See the following code:
rule "Null Check " salience 100
when
Salary ( ld : loanDeduction==null || <
0f ) // loanDeduction
is java.lang.Float
then
log("Load return is null");
//Global function
ld = 0f;
end
rule "Nett Salary" salience 70
when
Salary ( nett != ( gross – loanDeduction
– pf) )
then
log("Invalid nett salary
amount");
end
You may have idea what I am trying to do. But I get
NullPointerException in
“Nett Salary” rule when I fire the rules having fact
with null in the
loanDeduction attribute. I believe my “Null Check”
exception should execute
first and it does when I put negative value in
loadDeduction. What is
solution in such a case?
--
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http://www.nabble.com/NullPointerException-with-Wrapper-objects-tp2351550...
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