Unsatisfied dependencies exeption when using bean with interface

[janey]

Hello,

I am using JBoss M4 with Weld and I am getting a DeploymentException. I generally know the reasons for such exceptions, but this time I cant get rid of it.

I implemented the following classes:

@Named
@ConversationScoped
@Stateful(name = "AccountHome")
public class AccountHome extends HomeBean<Account, EntityManager> implements IAccount {
     
     // -- generated attribute, constant + association declarations ----------
     
     @Inject
     private BankHome bankHome;
     
     @Inject
     private CustomerHome customerHome;
   
[...]

// methods left out for better reading
}

and

@Named
@ConversationScoped
@Stateful(name = "BankHome")
public class BankHome extends HomeBean<Bank, EntityManager> {
     
     // -- generated attribute, constant + association declarations ----------
     
     @Inject
     private BankgroupHome bankgroupHome;
     
     @Inject
     private AccountHome accountHome;

[...]

// methods left out for better reading

}

and the interface:

public interface IAccount {
     
     /**
      * method stub for further implementation
      * @param     amount     
      * @return     
      */
     public boolean withdraw(float amount);
     
     /**
      * method stub for further implementation
      * @param     amount     
      * @return     
      */
     public boolean deposit(float amount);
     
     /**
      * method stub for further implementation
      * @return     
      */
     public AccountStateEnum getState();

}

On deployment I am getting the following exception:

11:10:22,337 ERROR [org.jboss.kernel.plugins.dependency.AbstractKernelController] Error installing to Start: name=vfs:///D:/Studium/Masterarbeit/JBoss/jboss-6.0.0.20100721-M4/server/default/deploy/Bank.ear_WeldBootstrapBean state=Create: org.jboss.weld.exceptions.DeploymentException: WELD-001408 Injection point has unsatisfied dependencies.  Injection point:  field Bank_Tutorial_Weld_Server.bankgroupServer.entity.BankHome.accountHome;  Qualifiers:  [@javax.enterprise.inject.Default()]
     at org.jboss.weld.bootstrap.Validator.validateInjectionPoint(Validator.java:276)
     at org.jboss.weld.bootstrap.Validator.validateBean(Validator.java:122)
     at org.jboss.weld.bootstrap.Validator.validateRIBean(Validator.java:141)
     at org.jboss.weld.bootstrap.Validator.validateBeans(Validator.java:331)
     at org.jboss.weld.bootstrap.Validator.validateDeployment(Validator.java:317)
     at org.jboss.weld.bootstrap.WeldBootstrap.validateBeans(WeldBootstrap.java:399)
     at org.jboss.weld.integration.deployer.env.helpers.BootstrapBean.boot(BootstrapBean.java:121) [:6.0.0.20100721-M4]
     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) [:1.6.0_16]
     at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) [:1.6.0_16]
     at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) [:1.6.0_16]
     at java.lang.reflect.Method.invoke(Method.java:597) [:1.6.0_16]
     at org.jboss.reflect.plugins.introspection.ReflectionUtils.invoke(ReflectionUtils.java:60) [jboss-reflect.jar:2.2.0.Alpha9]

I added the interface because I wanted to implement a decorator. So I created the following class:

@Decorator
abstract class AccountChecker implements IAccount, Serializable {
     
     // -- generated attribute, constant + association declarations ----------
     
     @Inject
     @Any
     @Delegate
     private IAccount account;

[...]

// methods left out for better reading
}

Without the interface for class AccountHome and without the decorator I dont get the exception and everything works fine. But with the interface the injection point of the class BankHome cannot be resolved any more.

What am I missing? I searched the internet, the forum and the specification for answers, but couldnt find anything that explains the situation. I want to use a decorator but I also want to inject the concrete class AccountHome into the BankHome class. Why isnt that possible any more?

I rather expected to get an ambiguous dependency exception than a unsatisfied dependencies exception.

Any ideas?

Thanks Janey

[janey]

Just an addition:

I found this in the documentation:

Obviously, if you have exactly one bean of a given type, and an injection point with that same type, then bean A is going to go into slot A.

So I thought the above code should work.

[cernicb]

Hello,
This is interesting. In jsr299, section 2.2 there is an example that says:

Meanwhile, this session bean has only the local interfaces BookShop and Auditable, along with Object, as bean types,
since the bean class is not a client-visible type.

@Stateful
public class BookShopBean
extends Business
implements BookShop, Auditable {
...
}

So, when session bean implements an interface, bean class itself is no longer a client-visible type. Do I understand correctly?

[janey]

Thats the way it seems to be. But for me it doesnt make sense. Its a kind of inconsequent without an interface a concrete class is a type and with an interface it is not??

Why?

[jharting]

So, when session bean implements an interface, bean class itself is no longer a client-visible type. Do I understand correctly?

Yes, unless you annotated the class with javax.ejb.LocalBean, in that case the session bean exposes a the class type as a client view.

[cernicb]

Jozef Hartinger wrote on Jan 05, 2011 08:59:


Yes, unless you annotated the class with javax.ejb.LocalBean, in that case the session bean exposes a the class type as a client view.

Thanks a lot. So, that's the bean class local view from cdi documentation, and the no-interface view from ejb 3.1 doc :).