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Posted to user@struts.apache.org by Mansour <ma...@yahoo.com> on 2007/05/26 16:39:46 UTC
session is null!
I am trying to setup a value in my session. IT works the first time I
call the action, and breaks the second time.
I get null pointer exception. This code is from my constructor.
Map session = ActionContext.getContext().getSession();
if (session.containsKey("InvoiceManager"))
this.invManager = (InvoiceManager)
session.get("InvoiceManager");
else {
invManager = new InvoiceManager();
session.put("InvoiceManager", invManager);
}
Here' the exception:
java.lang.NullPointerException
at action.InvoiceAction.<init>(InvoiceAction.java:25)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at
sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at
sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at java.lang.Class.newInstance0(Class.java:355)
at java.lang.Class.newInstance(Class.java:308)
Any Idea what's going on ?
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Re: session is null!
Posted by Dave Newton <ne...@yahoo.com>.
--- Mansour <ma...@yahoo.com> wrote:
> (5) Or trying to access the session in the Action
> constructor.
>
> I am not sure if this was my mistake. I would like
> to hear form some one.
As I've alluded to twice now, I believe it *is* your
mistake, at least if you're using SessionAware.
d.
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Re: session is null!
Posted by Mansour <ma...@yahoo.com>.
You missed one.
Paul Benedict wrote:
> Most people who have this problem do so because of four things: (1)
> they are
> switching protocols from HTTP/HTTPS (2) they are switching contexts
> (3) they
> are switching domains (4) they are invalidating the session.
(5) Or trying to access the session in the Action constructor.
I am not sure if this was my mistake. I would like to hear form some one.
By the way, can I save models on the ValueStack rather than the session ?
>
> -- Paul
>
> On 5/26/07, Dave Newton <ne...@yahoo.com> wrote:
>>
>> --- Mansour <ma...@yahoo.com> wrote:
>> > Thank you Dave for replying. I think I need a lot of
>> > help on this. The problem is even if I implement
>> > SessionAware, using chaining doesn't work as the
>> > setSession method is never called.
>>
>> Are you talking about the *second* action's
>> setSession()?
>>
>> Are you running a basicStack or stack that includes
>> the servletConfig interceptor on the action whose
>> setSession is *not* being called?
>>
>> At what point in the action object's lifecycle are you
>> attempting to access the session?
>>
>> d.
>>
>>
>>
>>
>> ____________________________________________________________________________________Got
>>
>> a little couch potato?
>> Check out fun summer activities for kids.
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>>
>>
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>>
>>
>
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Re: session is null!
Posted by Paul Benedict <pb...@apache.org>.
Most people who have this problem do so because of four things: (1) they are
switching protocols from HTTP/HTTPS (2) they are switching contexts (3) they
are switching domains (4) they are invalidating the session.
-- Paul
On 5/26/07, Dave Newton <ne...@yahoo.com> wrote:
>
> --- Mansour <ma...@yahoo.com> wrote:
> > Thank you Dave for replying. I think I need a lot of
> > help on this. The problem is even if I implement
> > SessionAware, using chaining doesn't work as the
> > setSession method is never called.
>
> Are you talking about the *second* action's
> setSession()?
>
> Are you running a basicStack or stack that includes
> the servletConfig interceptor on the action whose
> setSession is *not* being called?
>
> At what point in the action object's lifecycle are you
> attempting to access the session?
>
> d.
>
>
>
>
> ____________________________________________________________________________________Got
> a little couch potato?
> Check out fun summer activities for kids.
>
> http://search.yahoo.com/search?fr=oni_on_mail&p=summer+activities+for+kids&cs=bz
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: user-unsubscribe@struts.apache.org
> For additional commands, e-mail: user-help@struts.apache.org
>
>
Re: session is null!
Posted by Dave Newton <ne...@yahoo.com>.
--- Mansour <ma...@yahoo.com> wrote:
> Thank you Dave for replying. I think I need a lot of
> help on this. The problem is even if I implement
> SessionAware, using chaining doesn't work as the
> setSession method is never called.
Are you talking about the *second* action's
setSession()?
Are you running a basicStack or stack that includes
the servletConfig interceptor on the action whose
setSession is *not* being called?
At what point in the action object's lifecycle are you
attempting to access the session?
d.
____________________________________________________________________________________Got a little couch potato?
Check out fun summer activities for kids.
http://search.yahoo.com/search?fr=oni_on_mail&p=summer+activities+for+kids&cs=bz
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Re: session is null!
Posted by Mansour <ma...@yahoo.com>.
Thank you Dave for replying. I think I need a lot of help on this.
The problem is even if I implement SessionAware, using chaining doesn't
work as the setSession method is never called.
Dave Newton wrote:
> --- Mansour <ma...@yahoo.com> wrote:
>
>> Still this didn't help. i am still getting nulls for
>> the session in Action 2. CAn some one point me to a
>> link where I can get What I need ?
>>
>
> At this point I have no idea what state your code is
> in. You shouldn't need to deal with ActionContext at
> all if you're implementing SessionAware and have the
> normal interceptor stack.
>
> I have never had any issues accessing anything from
> the session, although the only way I have done so is
> via SessionAware. I also haven't put any complex
> behavior, particularly any relying on the framework or
> interceptors, into action constructors.
>
> d.
>
>
>
>
> ____________________________________________________________________________________
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Re: session is null!
Posted by Dave Newton <ne...@yahoo.com>.
--- Mansour <ma...@yahoo.com> wrote:
> Still this didn't help. i am still getting nulls for
> the session in Action 2. CAn some one point me to a
> link where I can get What I need ?
At this point I have no idea what state your code is
in. You shouldn't need to deal with ActionContext at
all if you're implementing SessionAware and have the
normal interceptor stack.
I have never had any issues accessing anything from
the session, although the only way I have done so is
via SessionAware. I also haven't put any complex
behavior, particularly any relying on the framework or
interceptors, into action constructors.
d.
____________________________________________________________________________________
The fish are biting.
Get more visitors on your site using Yahoo! Search Marketing.
http://searchmarketing.yahoo.com/arp/sponsoredsearch_v2.php
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Re: session is null!
Posted by Mansour <ma...@yahoo.com>.
OK,
Here's what I was to get so far.
I need to store and retrieve EntityManagers in the session Map.
I am using action chaining. Action 1 can get the session using
ActionContext.getContext.getSession(). However, action 2 always returns
null. To make things easier for myself I created a Top Level Base class
that implements SessionAware and extends ActionSupport, then I applied
chain interceptor to Action 2 so that values from Action 1 can be coped
to Action 2.
Still this didn't help. i am still getting nulls for the session in
Action 2. CAn some one point me to a link where I can get What I need ?
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Re: session is null!
Posted by Mansour <ma...@yahoo.com>.
I followed the dox and created an Action that implements SessionAware. I
set a break point and found the setSession is never called. Can someone
explain please?
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Re: session is null!
Posted by Mansour <ma...@yahoo.com>.
I found out what I was looking for:
http://struts.apache.org/2.0.6/docs/how-do-we-get-access-to-the-session.html
but still wondering why would ActionContext.getContext().getSession()
returns a session the first time it's called then it returns null?
Mansour wrote:
> I am trying to setup a value in my session. IT works the first time I
> call the action, and breaks the second time.
> I get null pointer exception. This code is from my constructor.
>
>
> Map session = ActionContext.getContext().getSession();
> if (session.containsKey("InvoiceManager"))
> this.invManager = (InvoiceManager)
> session.get("InvoiceManager");
> else {
> invManager = new InvoiceManager();
> session.put("InvoiceManager", invManager);
> }
>
>
> Here' the exception:
>
>
> java.lang.NullPointerException
> at action.InvoiceAction.<init>(InvoiceAction.java:25)
> at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native
> Method)
> at
> sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
>
> at
> sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
>
> at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
> at java.lang.Class.newInstance0(Class.java:355)
> at java.lang.Class.newInstance(Class.java:308)
>
>
>
>
> Any Idea what's going on ?
>
>
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> To unsubscribe, e-mail: user-unsubscribe@struts.apache.org
> For additional commands, e-mail: user-help@struts.apache.org
>
>
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