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[rules-users] (no subject)

Sandhya Sree
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

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Re: [rules-users] (no subject)

salaboy
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 <[hidden email]> 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

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--
 - MyJourney @ http://salaboy.com
 - Co-Founder @ http://www.jugargentina.org
 - Co-Founder @ http://www.jbug.com.ar
 
 - Salatino "Salaboy" Mauricio -

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Re: [rules-users] (no subject)

Sandhya Sree
Actually, il have to use this List<Event> in another class and then print list<Event> after every rule execution cycle.


On Mon, Mar 10, 2014 at 4:05 PM, Mauricio Salatino <[hidden email]> 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 <[hidden email]> 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
[hidden email]
https://lists.jboss.org/mailman/listinfo/rules-users



--
 - MyJourney @ http://salaboy.com
 - Co-Founder @ http://www.jugargentina.org
 - Co-Founder @ http://www.jbug.com.ar
 
 - Salatino "Salaboy" Mauricio -

_______________________________________________
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[hidden email]
https://lists.jboss.org/mailman/listinfo/rules-users


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Re: [rules-users] (no subject)

laune
In reply to this post by salaboy
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 <[hidden email]> 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
> <[hidden email]>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
>> [hidden email]
>> 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 -
>
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Re: [rules-users] (no subject)

Sandhya Sree
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 <[hidden email]> 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 <[hidden email]> 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
> <[hidden email]>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
>> [hidden email]
>> 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
[hidden email]
https://lists.jboss.org/mailman/listinfo/rules-users


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Re: [rules-users] (no subject)

salaboy
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 <[hidden email]> 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 <[hidden email]> 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 <[hidden email]> 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
> <[hidden email]>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
>> [hidden email]
>> 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
[hidden email]
https://lists.jboss.org/mailman/listinfo/rules-users


_______________________________________________
rules-users mailing list
[hidden email]
https://lists.jboss.org/mailman/listinfo/rules-users



--
 - MyJourney @ http://salaboy.com
 - Co-Founder @ http://www.jugargentina.org
 - Co-Founder @ http://www.jbug.com.ar
 
 - Salatino "Salaboy" Mauricio -

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Re: [rules-users] (no subject)

Sandhya Sree
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 <[hidden email]> 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 <[hidden email]> 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 <[hidden email]> 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 <[hidden email]> 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
> <[hidden email]>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
>> [hidden email]
>> 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
[hidden email]
https://lists.jboss.org/mailman/listinfo/rules-users


_______________________________________________
rules-users mailing list
[hidden email]
https://lists.jboss.org/mailman/listinfo/rules-users



--
 - MyJourney @ http://salaboy.com
 - Co-Founder @ http://www.jugargentina.org
 - Co-Founder @ http://www.jbug.com.ar
 
 - Salatino "Salaboy" Mauricio -

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[hidden email]
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Re: [rules-users] (no subject)

salaboy
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 <[hidden email]> 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 <[hidden email]> 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 <[hidden email]> 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 <[hidden email]> 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 <[hidden email]> 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
> <[hidden email]>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
>> [hidden email]
>> 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
[hidden email]
https://lists.jboss.org/mailman/listinfo/rules-users


_______________________________________________
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[hidden email]
https://lists.jboss.org/mailman/listinfo/rules-users



--
 - MyJourney @ http://salaboy.com
 - Co-Founder @ http://www.jugargentina.org
 - Co-Founder @ http://www.jbug.com.ar
 
 - Salatino "Salaboy" Mauricio -

_______________________________________________
rules-users mailing list
[hidden email]
https://lists.jboss.org/mailman/listinfo/rules-users


_______________________________________________
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[hidden email]
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--
 - MyJourney @ http://salaboy.com
 - Co-Founder @ http://www.jugargentina.org
 - Co-Founder @ http://www.jbug.com.ar
 
 - Salatino "Salaboy" Mauricio -

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Re: [rules-users] (no subject)

Sandhya Sree
Thanks :)
i got it :-)


On Mon, Mar 10, 2014 at 7:18 PM, Mauricio Salatino <[hidden email]> wrote:
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 <[hidden email]> 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 <[hidden email]> 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 <[hidden email]> 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 <[hidden email]> 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 <[hidden email]> 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
> <[hidden email]>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
>> [hidden email]
>> 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
[hidden email]
https://lists.jboss.org/mailman/listinfo/rules-users


_______________________________________________
rules-users mailing list
[hidden email]
https://lists.jboss.org/mailman/listinfo/rules-users



--
 - MyJourney @ http://salaboy.com
 - Co-Founder @ http://www.jugargentina.org
 - Co-Founder @ http://www.jbug.com.ar
 
 - Salatino "Salaboy" Mauricio -

_______________________________________________
rules-users mailing list
[hidden email]
https://lists.jboss.org/mailman/listinfo/rules-users


_______________________________________________
rules-users mailing list
[hidden email]
https://lists.jboss.org/mailman/listinfo/rules-users



--
 - MyJourney @ http://salaboy.com
 - Co-Founder @ http://www.jugargentina.org
 - Co-Founder @ http://www.jbug.com.ar
 
 - Salatino "Salaboy" Mauricio -

_______________________________________________
rules-users mailing list
[hidden email]
https://lists.jboss.org/mailman/listinfo/rules-users


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Re: [rules-users] (no subject)

laune
In reply to this post by Sandhya Sree
Initializing references to objects is always a good idea to avoid NPE.
-W

On 10/03/2014, Sandhya Sree <[hidden email]> 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
> <[hidden email]>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 <[hidden email]> 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
>> > <[hidden email]>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
>> >> [hidden email]
>> >> 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
>> [hidden email]
>> https://lists.jboss.org/mailman/listinfo/rules-users
>>
>
_______________________________________________
rules-users mailing list
[hidden email]
https://lists.jboss.org/mailman/listinfo/rules-users