@PostConstruct method called twice for the same request
Solution 1
That can happen if you have multiple frameworks managing the same bean class. E.g. JSF and CDI, or JSF and Spring, or CDI and Spring, etc. Doublecheck your configuration and annotations on the bean.
That can also happen if you're using CDI and are using multiple @Named
annotations throughout the class. For example, a @Named
straight on the class to register it as a managed bean and another one on a @Produces
getter method. You'd need to ask yourself whether that is really necessary. You could also just use #{bean.someObject}
instead of #{someObject}
.
@Named
@RequestScoped
public class Bean {
@PostConstruct
public void init() {
// ...
}
@Named
@Produces
public SomeObject getSomeObject() {
// ...
}
}
That can also happen if your managed bean extends some abstract class which has in turn also a @PostConstruct
on the method. You should remove the annotation from it. Alternatively, you should make the init method abstract and not have @PostConstruct
on the implementing bean:
public abstract class BaseBean {
@PostConstruct
public void postConstruct() {
init();
}
public abstract void init();
}
Solution 2
It is possible that the both init()
method and @PostConstruct
methods are firing and causing this behavior. Try changing the name of the init()
method and/or putting it private
. I think that this may be related to your problems:
http://javahowto.blogspot.com/2011/07/servlet-init-method-vs-postconstruct.html
I also found a good post about debugging JSF life cycles here: Debug JSF lifecycle
Related videos on Youtube
Ionut
Updated on July 09, 2022Comments
-
Ionut almost 2 years
I'm using JSF 2.0 with GlassFish 3.0.
I have the following Managed Bean:
@ManagedBean @RequestScoped public class OverviewController{ private List<Event> eventList; @PostConstruct public void init(){ System.out.println("=> OverviewController - init() - enter"); System.out.println("=< OverviewController - init() - exit"); } }
From the the overview.xhtml file I'm calling different attributes or methods from my OverviewController.
<ui:repeat var="event" value="#{overviewController.eventList}"> ... </ui:repeat>
Everything works just fine but the problem is on the Log File:
INFO: Enter : RESTORE_VIEW 1 INFO: Exit : RESTORE_VIEW 1 INFO: Enter : RENDER_RESPONSE 6 INFO: => OverviewController - init() - enter INFO: => Overview Controller - updateSelectedTab() - enter INFO: =< Overview Controller - updateSelectedTab() - exit INFO: =< OverviewController - init() - exit INFO: => OverviewController - init() - enter INFO: => Overview Controller - updateSelectedTab() - enter INFO: =< Overview Controller - updateSelectedTab() - exit INFO: =< OverviewController - init() - exit INFO: Exit : RENDER_RESPONSE 6
As you can see, The init() method is called twice in the same request for no reason what so ever. From what I know, any method annotated with PostConstruct is called once every request. Am I wrong?
EDIT: No AJAX is used on the page. I checked the number of requests with firebug. There are tree requests made:
- 1.One for the javax.faces.resource (GET)
- 2.One for the css file (GET)
- 3.One for overview.xhtml (GET)
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Kushan over 12 yearsAre you mean ClassFish or GlassFish?
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MrKiane over 12 yearsAre you performing any Ajax calls? Use FireBug or similar add on to find out how many requests the browser is actually making.
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Ionut over 12 years@PederN I updated the question.
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MrKiane over 12 yearsOn this page there are some tips for debugging JSF lifecycles. Check it out, maybe it is something there that can help you balusc.blogspot.com/2006/09/debug-jsf-lifecycle.html
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Ionut over 12 yearsThanks! Sadly I couldn't find there anything which could explain my problem. It seems that all the methods annotated with @PostConstruct are called twice in Invoke Application or RenderResponse
-
MrKiane over 12 yearsWhat if you name the
init()
method something else, such asmyInit()
? init() method was used before to initialize servlets (AFAIK), could it be that Glassfish is running init() in one state of the life cycle and @PostConstruct in another? Is this related? javahowto.blogspot.com/2011/07/…
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BalusC over 12 yearsThis makes no sense. A JSF managed bean is not a
HttpServlet
implementation. -
MrKiane over 12 yearsI meant that depending on configuration it may cause the system to get confused and fire on both methods. Maybe it was a long shot though. Thanks for your clarification.
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Ionut over 12 yearsI tried removing the annotation but then the init() would be ignored. As BalusC said it seems that there is no init() method in a managed bean.
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BalusC over 12 years@Peder: JSF has absolutely no special treatment for methods called
init()
. You're confusing withHttpServlet#init()
. Please re-read the javahowto article which you linked yourself. -
Ionut over 12 yearsThanks! I don't have multiple frameworks but this helped me to understand what the problem was. All my ManagedBeans extend a
BaseController
. This BaseController has a@PostConstruct init()
method which I thought it would be override by the other ManagedBeans'PostConstruct init()
. It seems though that bothinit()
are called. It all makes sense now.. Thank you! -
BalusC over 12 yearsYou should not have
@PostConstruct
in theBaseController
class. Remove it. -
Mr.J4mes over 12 years@BalusC: I have a small side question. Regarding using JSF and CDI on the same bean, if I use
@Inject
to inject a CDI bean into a@ManagedBean
, will the@PostConstruct
method be called twice? I'm not quite sure how to apply multiple framework on the same bean. I thought that the framework was decided by annotated the bean with@ManagedBean
,@Named
, etc. -
Half Blood Prince almost 8 years@BalusC I have the same problem. I have defined
@PostConstruct
method inside@Controller
class. Is there any problem in it? Actually, I want to start my scheduler on app deployment. Is there any other way?