[rules-users] (no subject)
Mauricio Salatino
salaboy at gmail.com
Mon Mar 10 09:48:17 EDT 2014
If the list inside Event has never being initialised it will throw a null
point exception.. so you need to make sure that the list
is initialised properly.
Regards
On Mon, Mar 10, 2014 at 1:43 PM, Sandhya Sree <sandhyachinnaraj at gmail.com>wrote:
> Exception in thread "pool-2-thread-1" Exception executing consequence for
> rule "size" in com.net: java.lang.NullPointerException
> at
> org.drools.runtime.rule.impl.DefaultConsequenceExceptionHandler.handleException(DefaultConsequenceExceptionHandler.java:39)
> at
> org.drools.common.DefaultAgenda.fireActivation(DefaultAgenda.java:1297)
> at org.drools.common.DefaultAgenda.fireNextItem(DefaultAgenda.java:1221)
> at org.drools.common.DefaultAgenda.fireAllRules(DefaultAgenda.java:1456)
> at
> org.drools.common.AbstractWorkingMemory.fireAllRules(AbstractWorkingMemory.java:710)
> at
> org.drools.common.AbstractWorkingMemory.fireAllRules(AbstractWorkingMemory.java:674)
> at
> org.drools.impl.StatefulKnowledgeSessionImpl.fireAllRules(StatefulKnowledgeSessionImpl.java:230)
> at com.net.RuleExecutor.execute(RuleExecutor.java:18)
> at com.net.DirectoryMonitor.run(DirectoryMonitor.java:39)
> at
> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
> at
> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
> at java.lang.Thread.run(Thread.java:744)
> Caused by: java.lang.NullPointerException
> at
> com.net.Rule_size_dc2a47e2812648e69eb9581eda931496.defaultConsequence(Rule_size_dc2a47e2812648e69eb9581eda931496.java:9)
> at
> com.net.Rule_size_dc2a47e2812648e69eb9581eda931496DefaultConsequenceInvokerGenerated.evaluate(Unknown
> Source)
> at
> com.net.Rule_size_dc2a47e2812648e69eb9581eda931496DefaultConsequenceInvoker.evaluate(Unknown
> Source)
> at
> org.drools.common.DefaultAgenda.fireActivation(DefaultAgenda.java:1287)
>
>
> On Mon, Mar 10, 2014 at 7:08 PM, Mauricio Salatino <salaboy at gmail.com>wrote:
>
>> Please copy the entire stack trace.. what you have copied doesn't mean
>> anything besides that there is something wrong.
>>
>>
>> On Mon, Mar 10, 2014 at 1:29 PM, Sandhya Sree <sandhyachinnaraj at gmail.com
>> > wrote:
>>
>>> im getting the following error on doing that
>>>
>>> Exception in thread "pool-2-thread-1" Exception executing consequence
>>> for rule "size" in com.net: java.lang.NullPointerException
>>>
>>> what might be the problem?
>>>
>>>
>>>
>>> On Mon, Mar 10, 2014 at 4:16 PM, Wolfgang Laun <wolfgang.laun at gmail.com>wrote:
>>>
>>>> Seeing that the list is static you can use the usual way for accessing
>>>> a static class member:
>>>>
>>>> Event.listOfEvent.add( ... );
>>>>
>>>> @Mauricio: It's not unusual to maintain a static collection (even
>>>> though there may be better ways, esp. with Drools).
>>>>
>>>>
>>>>
>>>> On 10/03/2014, Mauricio Salatino <salaboy at gmail.com> wrote:
>>>> > Can you please elaborate about why do you want to do that? what's the
>>>> point
>>>> > of having a list inside of the Event class that will contain the same
>>>> > event?
>>>> >
>>>> > The "Then" side of the rule is pure java.. so you just do
>>>> > event.getEvents().add(event);
>>>> >
>>>> > but I don't see the point of doing that.
>>>> >
>>>> > Regards
>>>> >
>>>> >
>>>> > On Mon, Mar 10, 2014 at 10:31 AM, Sandhya Sree
>>>> > <sandhyachinnaraj at gmail.com>wrote:
>>>> >
>>>> >> hi ,
>>>> >>
>>>> >> i have a class called Event which is as follows:
>>>> >>
>>>> >> public class Event {
>>>> >> private String name;
>>>> >> private File source;
>>>> >> private Date timeStamp;
>>>> >> public static List<Event> listOfEvents;
>>>> >>
>>>> >> public Event(String name, File source, Date timeStamp) {
>>>> >> this.name = name;
>>>> >> this.source = source;
>>>> >> this.timeStamp = timeStamp;
>>>> >> }
>>>> >> public String getName() {
>>>> >> return name;
>>>> >> }
>>>> >> public void setName(String name) {
>>>> >> this.name = name;
>>>> >> }
>>>> >> public File getSource() {
>>>> >> return source;
>>>> >> }
>>>> >> public void setSource(File source) {
>>>> >> this.source = source;
>>>> >> }
>>>> >> public Date getTimeStamp() {
>>>> >> return timeStamp;
>>>> >> }
>>>> >> public void setTimeStamp(Date timeStamp) {
>>>> >> this.timeStamp = timeStamp;
>>>> >> }
>>>> >>
>>>> >>
>>>> >> public void display()
>>>> >> {
>>>> >> System.out.println(name +" " + "in folder: " + source + " on " +
>>>> >> timeStamp );
>>>> >> }
>>>> >>
>>>> >>
>>>> >>
>>>> >> there are also some other classes associated with my project.. i
>>>> have a
>>>> >> rules file which computes the size of a folder and creates an object
>>>> of
>>>> >> Event class. every time this object of Event class is created i
>>>> wwant to
>>>> >> put it in a List<Event>.. how can i do this..
>>>> >>
>>>> >> my rules is as follows:
>>>> >>
>>>> >> rule "size"
>>>> >> when
>>>> >> $p: RuleContext($size:
>>>> getOldContext().getParent().getUsableSpace() >
>>>> >> (30*1024*1024))
>>>> >>
>>>> >> then
>>>> >> Event event = new Event("folder almost full",
>>>> >> $p.getOldContext().getParent(), new Date());
>>>> >> event.display();
>>>> >> ......here i want to put this event into the List<Event> declared
>>>> in
>>>> >> Event Class.....
>>>> >>
>>>> >> end
>>>> >>
>>>> >>
>>>> >>
>>>> >> thanks,
>>>> >> Sandhya
>>>> >>
>>>> >> _______________________________________________
>>>> >> rules-users mailing list
>>>> >> rules-users at lists.jboss.org
>>>> >> https://lists.jboss.org/mailman/listinfo/rules-users
>>>> >>
>>>> >
>>>> >
>>>> >
>>>> > --
>>>> > - MyJourney @ http://salaboy.com <http://salaboy.wordpress.com>
>>>> > - Co-Founder @ http://www.jugargentina.org
>>>> > - Co-Founder @ http://www.jbug.com.ar
>>>> >
>>>> > - Salatino "Salaboy" Mauricio -
>>>> >
>>>> _______________________________________________
>>>> rules-users mailing list
>>>> rules-users at lists.jboss.org
>>>> https://lists.jboss.org/mailman/listinfo/rules-users
>>>>
>>>
>>>
>>> _______________________________________________
>>> rules-users mailing list
>>> rules-users at lists.jboss.org
>>> https://lists.jboss.org/mailman/listinfo/rules-users
>>>
>>
>>
>>
>> --
>> - MyJourney @ http://salaboy.com <http://salaboy.wordpress.com>
>> - Co-Founder @ http://www.jugargentina.org
>> - Co-Founder @ http://www.jbug.com.ar
>>
>> - Salatino "Salaboy" Mauricio -
>>
>> _______________________________________________
>> rules-users mailing list
>> rules-users at lists.jboss.org
>> https://lists.jboss.org/mailman/listinfo/rules-users
>>
>
>
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--
- MyJourney @ http://salaboy.com <http://salaboy.wordpress.com>
- Co-Founder @ http://www.jugargentina.org
- Co-Founder @ http://www.jbug.com.ar
- Salatino "Salaboy" Mauricio -
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