Re: NullPointer for service constructor
I'm sure Tapestry could do some byte code magic via plastic such that any @Inject fields accessed in the constructor were swapped out for getters with nice error messages. Sounds very messy / intrusive to me and I don't think it should be implemented. On 7 Apr 2014 13:54, Thiago H de Paula Figueiredo thiag...@gmail.com wrote: On Sun, 06 Apr 2014 16:26:47 -0300, John j...@quivinco.com wrote: problem solved, the Logger was of course not yet injected! Duh. I wish the IoC stack dump were more helpful. I'm not sure how (a better error message) that could be done. How could Tapestry-IoC differentiate an exception caused by field injection not done yet from other exceptions? Even if it's just about NPEs, I cannot see how that could be done. -- Thiago H. de Paula Figueiredo Tapestry, Java and Hibernate consultant and developer http://machina.com.br - To unsubscribe, e-mail: users-unsubscr...@tapestry.apache.org For additional commands, e-mail: users-h...@tapestry.apache.org
Re: NullPointer for service constructor
On Tue, 08 Apr 2014 05:23:13 -0300, Lance Java lance.j...@googlemail.com wrote: I'm sure Tapestry could do some byte code magic via plastic such that any @Inject fields accessed in the constructor were swapped out for getters with nice error messages. Sounds very messy / intrusive to me and I don't think it should be implemented. Hi, Lance! Hmmm, you're right, that's probably very doable (I'm not sure Plastic already handles throwing exceptions, and it supports just the bytecode it needs). You've thought in an angle I haven't though. :) Regarding being implemented or not, I think this kind of NPE is one that occurs in the exact same way with ordinary, non-Tapestry-IoC Java, so I agree that I shouldn't be implemented and that constructor injection is the recommended one. On 7 Apr 2014 13:54, Thiago H de Paula Figueiredo thiag...@gmail.com wrote: On Sun, 06 Apr 2014 16:26:47 -0300, John j...@quivinco.com wrote: problem solved, the Logger was of course not yet injected! Duh. I wish the IoC stack dump were more helpful. I'm not sure how (a better error message) that could be done. How could Tapestry-IoC differentiate an exception caused by field injection not done yet from other exceptions? Even if it's just about NPEs, I cannot see how that could be done. -- Thiago H. de Paula Figueiredo Tapestry, Java and Hibernate consultant and developer http://machina.com.br - To unsubscribe, e-mail: users-unsubscr...@tapestry.apache.org For additional commands, e-mail: users-h...@tapestry.apache.org -- Thiago H. de Paula Figueiredo Tapestry, Java and Hibernate consultant and developer http://machina.com.br - To unsubscribe, e-mail: users-unsubscr...@tapestry.apache.org For additional commands, e-mail: users-h...@tapestry.apache.org
Re: NullPointer for service constructor
Hi t5 aficionados, Am I correct in following this thread...that it is best to think of @inject as lazy inject? (After constructor) If so, without knowledge of tapestry internally, sounds like a familiar gotcha like onActivate/setupRender and instantiation/fetching-stuff That plastic morphing sounds like a can of worms btw Chasing-those-exceptions is never fun, although I'd prefer to do that than compliance documentation and openssl heartbleed shenanigans! Cant believe it'll be Wednesday soon! Cheers Chris On 08/04/2014 9:07 pm, Thiago H de Paula Figueiredo thiag...@gmail.com wrote: On Tue, 08 Apr 2014 05:23:13 -0300, Lance Java lance.j...@googlemail.com wrote: I'm sure Tapestry could do some byte code magic via plastic such that any @Inject fields accessed in the constructor were swapped out for getters with nice error messages. Sounds very messy / intrusive to me and I don't think it should be implemented. Hi, Lance! Hmmm, you're right, that's probably very doable (I'm not sure Plastic already handles throwing exceptions, and it supports just the bytecode it needs). You've thought in an angle I haven't though. :) Regarding being implemented or not, I think this kind of NPE is one that occurs in the exact same way with ordinary, non-Tapestry-IoC Java, so I agree that I shouldn't be implemented and that constructor injection is the recommended one. On 7 Apr 2014 13:54, Thiago H de Paula Figueiredo thiag...@gmail.com wrote: On Sun, 06 Apr 2014 16:26:47 -0300, John j...@quivinco.com wrote: problem solved, the Logger was of course not yet injected! Duh. I wish the IoC stack dump were more helpful. I'm not sure how (a better error message) that could be done. How could Tapestry-IoC differentiate an exception caused by field injection not done yet from other exceptions? Even if it's just about NPEs, I cannot see how that could be done. -- Thiago H. de Paula Figueiredo Tapestry, Java and Hibernate consultant and developer http://machina.com.br - To unsubscribe, e-mail: users-unsubscr...@tapestry.apache.org For additional commands, e-mail: users-h...@tapestry.apache.org -- Thiago H. de Paula Figueiredo Tapestry, Java and Hibernate consultant and developer http://machina.com.br - To unsubscribe, e-mail: users-unsubscr...@tapestry.apache.org For additional commands, e-mail: users-h...@tapestry.apache.org
Re: NullPointer for service constructor
On Tue, 08 Apr 2014 10:04:20 -0300, Chris Mylonas ch...@opencsta.org wrote: Hi t5 aficionados, Hi! Am I correct in following this thread...that it is best to think of @inject as lazy inject? (After constructor) No. It's not lazy because the injection is done before the service instance. If so, without knowledge of tapestry internally, sounds like a familiar gotcha like onActivate/setupRender and instantiation/fetching-stuff I'm sorry, but the analogy is completely off. That plastic morphing sounds like a can of worms btw Actually, no, this isn't related to Plastic at all. That NPE would happen in the exact same way in Spring. Again, service classes are *not* transformed by Plastic at all. Instead, it creates proxies that delegate method calls to the service instances. Just Tapestry pages, components, mixins and classes in the base package are transformed. Chasing-those-exceptions is never fun, although I'd prefer to do that than compliance documentation and openssl heartbleed shenanigans! Cant believe it'll be Wednesday soon! Whoosh! :D -- Thiago H. de Paula Figueiredo Tapestry, Java and Hibernate consultant and developer http://machina.com.br - To unsubscribe, e-mail: users-unsubscr...@tapestry.apache.org For additional commands, e-mail: users-h...@tapestry.apache.org
Re: NullPointer for service constructor
FYI, in spring ioc you work around this issue via implementing InitializingBean.afterPropertiesSet() http://docs.spring.io/spring/docs/2.5.6/api/org/springframework/beans/factory/InitializingBean.html As has been mentioned many times here, constructor injection is superior to field injection for many reasons
Re: NullPointer for service constructor
It seems like tapestry ioc has @PostInjection ( https://tapestry.apache.org/injection-in-detail.html#InjectioninDetail-Post-InjectionMethods) to receive a callback after the instance is configured.Somewhat similar to the afterPropertiesSet(). On Tue, Apr 8, 2014 at 3:55 PM, Lance Java lance.j...@googlemail.comwrote: FYI, in spring ioc you work around this issue via implementing InitializingBean.afterPropertiesSet() http://docs.spring.io/spring/docs/2.5.6/api/org/springframework/beans/factory/InitializingBean.html As has been mentioned many times here, constructor injection is superior to field injection for many reasons
Re: NullPointer for service constructor
On Sun, 06 Apr 2014 16:26:47 -0300, John j...@quivinco.com wrote: problem solved, the Logger was of course not yet injected! Duh. I wish the IoC stack dump were more helpful. I'm not sure how (a better error message) that could be done. How could Tapestry-IoC differentiate an exception caused by field injection not done yet from other exceptions? Even if it's just about NPEs, I cannot see how that could be done. -- Thiago H. de Paula Figueiredo Tapestry, Java and Hibernate consultant and developer http://machina.com.br - To unsubscribe, e-mail: users-unsubscr...@tapestry.apache.org For additional commands, e-mail: users-h...@tapestry.apache.org
Re: NullPointer for service constructor
problem solved, the Logger was of course not yet injected! Duh. I wish the IoC
stack dump were more helpful.
J
- Original Message -
From: John
To: users@tapestry.apache.org
Sent: Sunday, April 06, 2014 6:35 PM
Subject: NullPointer for service constructor
I'm trying to constuct a service implimentation that receives references to a
couple of other services that registers the objects into a super class. But I
get a null pointer exception.
What am I doing wrong here?
public class AppModule {
public static void bind(ServiceBinder binder) {
// bind low-level services and utilities
binder.bind(CommonsEmailNotificationSender.class); // implements
NotificationSender to send email
binder.bind(TextMarketerNotificationSender.class); // implements
NotificationSender to send sms
...
// bind facades
...
binder.bind(NotificationSenderFacade.class,
DefaultNotificationSenderFacade.class); // combines the NotificationSender
instances above
}
public interface NotificationSender {
boolean sendNotification(String toUsername, String fromUsername, String
replyto, String to, String messageText, boolean admin);
boolean sendNotificationLater(String toUsername, String fromUsername,
String replyto, String to, String messageText, boolean admin);
public interface NotificationSenderFacade {
NotificationSender getNotificationSender(String classnme);
boolean sendNotification(String toUsername, String fromUsername,
ListNotificationRoutingroutes, String messageText, boolean admin);
boolean sendNotificationLater(String toUsername, String fromUsername,
ListNotificationRoutingroutes, String messageText, boolean admin);
public abstract class AbstractNotificationSenderFacade implements
NotificationSenderFacade {
/**
* The log.
*/
@Inject
private Logger log;
private MapString, NotificationSender notificationSenders
= new HashMapString, NotificationSender();
// put the notification senders into a map during subclass construction
protected void registerNotificationSender(NotificationSender
notificationSender) {
String classname = notificationSender.getClass().getSimpleName();
notificationSenders.put(classname, notificationSender);
log.info(registered + classname);
}
@EagerLoad
public class DefaultNotificationSenderFacade extends
AbstractNotificationSenderFacade {
/**
* The log.
*/
@Inject
private Logger log;
/**
* Create the facade for the given the notification senders.
*
* @param emailNotificationSender
* @param smsNotificationSender
*/
public DefaultNotificationSenderFacade(CommonsEmailNotificationSender
emailNotificationSender,
TextMarketerNotificationSender smsNotificationSender) {
super();
super.registerNotificationSender(emailNotificationSender);
super.registerNotificationSender(smsNotificationSender);
log.debug(registered notification senders);
}
@Override
public boolean sendNotification(String toUsername, String fromUsername,
ListNotificationRouting routes, String messageText, boolean admin) {
boolean success = true;
for (NotificationRouting route : routes) {
if (route.getTo().contains(@)) {
boolean done =
super.getNotificationSender(CommonsEmailNotificationSender)
.sendNotification(toUsername, fromUsername,
route.getReplyto(), route.getTo(), messageText, admin);
AppModule.NotificationSenderFacade Loading class
com.quivinco.webapps.tbs.utils.DefaultNotificationSenderFacade.
AppModule.NotificationSenderFacade Marking class
com.quivinco.webapps.tbs.utils.DefaultNotificationSenderFacade to be (re-)loaded
AppModule.NotificationSenderFacade BEGIN Analyzing
com.quivinco.webapps.tbs.utils.DefaultNotificationSenderFacade
AppModule.NotificationSenderFacade Marking class
com.quivinco.webapps.tbs.utils.AbstractNotificationSenderFacade to be
(re-)loaded
AppModule.NotificationSenderFacade BEGIN Analyzing
com.quivinco.webapps.tbs.utils.AbstractNotificationSenderFacade
AppModule.NotificationSenderFacade END Analyzing
com.quivinco.webapps.tbs.utils.AbstractNotificationSenderFacade
AppModule.NotificationSenderFacade END Analyzing
com.quivinco.webapps.tbs.utils.DefaultNotificationSenderFacade
AppModule.CommonsEmailNotificationSender Creating non-proxied instance of
service CommonsEmailNotificationSender
AppModule.CommonsEmailNotificationSender Invoking constructor
com.quivinco.webapps.tbs.utils.CommonsEmailNotificationSender() (at
CommonsEmailNotificationSender.java:23) via
com.quivinco.webapps.tbs.services.AppModule.bind(ServiceBinder) (at
AppModule.java:75) (for service 'CommonsEmailNotificationSender')
Re: NullPointer for service constructor
I battled with the same issue yesterday - injection happens after the
constructor has run!
On Sun, Apr 6, 2014 at 9:26 PM, John j...@quivinco.com wrote:
problem solved, the Logger was of course not yet injected! Duh. I wish the
IoC stack dump were more helpful.
J
- Original Message -
From: John
To: users@tapestry.apache.org
Sent: Sunday, April 06, 2014 6:35 PM
Subject: NullPointer for service constructor
I'm trying to constuct a service implimentation that receives references
to a couple of other services that registers the objects into a super
class. But I get a null pointer exception.
What am I doing wrong here?
public class AppModule {
public static void bind(ServiceBinder binder) {
// bind low-level services and utilities
binder.bind(CommonsEmailNotificationSender.class); // implements
NotificationSender to send email
binder.bind(TextMarketerNotificationSender.class); // implements
NotificationSender to send sms
...
// bind facades
...
binder.bind(NotificationSenderFacade.class,
DefaultNotificationSenderFacade.class); // combines the NotificationSender
instances above
}
public interface NotificationSender {
boolean sendNotification(String toUsername, String fromUsername,
String replyto, String to, String messageText, boolean admin);
boolean sendNotificationLater(String toUsername, String
fromUsername, String replyto, String to, String messageText, boolean admin);
public interface NotificationSenderFacade {
NotificationSender getNotificationSender(String classnme);
boolean sendNotification(String toUsername, String fromUsername,
ListNotificationRoutingroutes, String messageText, boolean admin);
boolean sendNotificationLater(String toUsername, String
fromUsername, ListNotificationRoutingroutes, String messageText, boolean
admin);
public abstract class AbstractNotificationSenderFacade implements
NotificationSenderFacade {
/**
* The log.
*/
@Inject
private Logger log;
private MapString, NotificationSender notificationSenders
= new HashMapString, NotificationSender();
// put the notification senders into a map during subclass
construction
protected void registerNotificationSender(NotificationSender
notificationSender) {
String classname = notificationSender.getClass().getSimpleName();
notificationSenders.put(classname, notificationSender);
log.info(registered + classname);
}
@EagerLoad
public class DefaultNotificationSenderFacade extends
AbstractNotificationSenderFacade {
/**
* The log.
*/
@Inject
private Logger log;
/**
* Create the facade for the given the notification senders.
*
* @param emailNotificationSender
* @param smsNotificationSender
*/
public
DefaultNotificationSenderFacade(CommonsEmailNotificationSender
emailNotificationSender,
TextMarketerNotificationSender smsNotificationSender) {
super();
super.registerNotificationSender(emailNotificationSender);
super.registerNotificationSender(smsNotificationSender);
log.debug(registered notification senders);
}
@Override
public boolean sendNotification(String toUsername, String
fromUsername, ListNotificationRouting routes, String messageText, boolean
admin) {
boolean success = true;
for (NotificationRouting route : routes) {
if (route.getTo().contains(@)) {
boolean done =
super.getNotificationSender(CommonsEmailNotificationSender)
.sendNotification(toUsername, fromUsername,
route.getReplyto(), route.getTo(), messageText, admin);
AppModule.NotificationSenderFacade Loading class
com.quivinco.webapps.tbs.utils.DefaultNotificationSenderFacade.
AppModule.NotificationSenderFacade Marking class
com.quivinco.webapps.tbs.utils.DefaultNotificationSenderFacade to be
(re-)loaded
AppModule.NotificationSenderFacade BEGIN Analyzing
com.quivinco.webapps.tbs.utils.DefaultNotificationSenderFacade
AppModule.NotificationSenderFacade Marking class
com.quivinco.webapps.tbs.utils.AbstractNotificationSenderFacade to be
(re-)loaded
AppModule.NotificationSenderFacade BEGIN Analyzing
com.quivinco.webapps.tbs.utils.AbstractNotificationSenderFacade
AppModule.NotificationSenderFacade END Analyzing
com.quivinco.webapps.tbs.utils.AbstractNotificationSenderFacade
AppModule.NotificationSenderFacade END Analyzing
com.quivinco.webapps.tbs.utils.DefaultNotificationSenderFacade
AppModule.CommonsEmailNotificationSender Creating non-proxied instance
of service CommonsEmailNotificationSender
AppModule.CommonsEmailNotificationSender Invoking constructor
Re: NullPointer for service constructor
Constructor injection has these three distinct advantages over field/setter
injection:
- always thread safe
- fields can be marked final
- you don't have to keep references to objects you need during construction
Kalle
On Sun, Apr 6, 2014 at 1:08 PM, Sanket Sharma sanketsha...@gmail.comwrote:
I battled with the same issue yesterday - injection happens after the
constructor has run!
On Sun, Apr 6, 2014 at 9:26 PM, John j...@quivinco.com wrote:
problem solved, the Logger was of course not yet injected! Duh. I wish
the
IoC stack dump were more helpful.
J
- Original Message -
From: John
To: users@tapestry.apache.org
Sent: Sunday, April 06, 2014 6:35 PM
Subject: NullPointer for service constructor
I'm trying to constuct a service implimentation that receives
references
to a couple of other services that registers the objects into a super
class. But I get a null pointer exception.
What am I doing wrong here?
public class AppModule {
public static void bind(ServiceBinder binder) {
// bind low-level services and utilities
binder.bind(CommonsEmailNotificationSender.class); //
implements
NotificationSender to send email
binder.bind(TextMarketerNotificationSender.class); //
implements
NotificationSender to send sms
...
// bind facades
...
binder.bind(NotificationSenderFacade.class,
DefaultNotificationSenderFacade.class); // combines the
NotificationSender
instances above
}
public interface NotificationSender {
boolean sendNotification(String toUsername, String fromUsername,
String replyto, String to, String messageText, boolean admin);
boolean sendNotificationLater(String toUsername, String
fromUsername, String replyto, String to, String messageText, boolean
admin);
public interface NotificationSenderFacade {
NotificationSender getNotificationSender(String classnme);
boolean sendNotification(String toUsername, String fromUsername,
ListNotificationRoutingroutes, String messageText, boolean admin);
boolean sendNotificationLater(String toUsername, String
fromUsername, ListNotificationRoutingroutes, String messageText,
boolean
admin);
public abstract class AbstractNotificationSenderFacade implements
NotificationSenderFacade {
/**
* The log.
*/
@Inject
private Logger log;
private MapString, NotificationSender notificationSenders
= new HashMapString, NotificationSender();
// put the notification senders into a map during subclass
construction
protected void registerNotificationSender(NotificationSender
notificationSender) {
String classname =
notificationSender.getClass().getSimpleName();
notificationSenders.put(classname, notificationSender);
log.info(registered + classname);
}
@EagerLoad
public class DefaultNotificationSenderFacade extends
AbstractNotificationSenderFacade {
/**
* The log.
*/
@Inject
private Logger log;
/**
* Create the facade for the given the notification senders.
*
* @param emailNotificationSender
* @param smsNotificationSender
*/
public
DefaultNotificationSenderFacade(CommonsEmailNotificationSender
emailNotificationSender,
TextMarketerNotificationSender smsNotificationSender) {
super();
super.registerNotificationSender(emailNotificationSender);
super.registerNotificationSender(smsNotificationSender);
log.debug(registered notification senders);
}
@Override
public boolean sendNotification(String toUsername, String
fromUsername, ListNotificationRouting routes, String messageText,
boolean
admin) {
boolean success = true;
for (NotificationRouting route : routes) {
if (route.getTo().contains(@)) {
boolean done =
super.getNotificationSender(CommonsEmailNotificationSender)
.sendNotification(toUsername, fromUsername,
route.getReplyto(), route.getTo(), messageText, admin);
AppModule.NotificationSenderFacade Loading class
com.quivinco.webapps.tbs.utils.DefaultNotificationSenderFacade.
AppModule.NotificationSenderFacade Marking class
com.quivinco.webapps.tbs.utils.DefaultNotificationSenderFacade to be
(re-)loaded
AppModule.NotificationSenderFacade BEGIN Analyzing
com.quivinco.webapps.tbs.utils.DefaultNotificationSenderFacade
AppModule.NotificationSenderFacade Marking class
com.quivinco.webapps.tbs.utils.AbstractNotificationSenderFacade to be
(re-)loaded
AppModule.NotificationSenderFacade BEGIN Analyzing
