9

I try to build a Webapp with the MVP paradigm. Because I want the API to be clean and make everything easy testable I try to inject everything possible via Contructor Injection. Now I came to a point where I have a view with multiple Textfields. These Textfields get filled by the presenter when there are values for it in the DB so my presenter needs a reference of the view but the vie obviously needs a reference of the Presenter, too. CDI tells me that injection of Presenter into the view and otherwise is not possible because of circular dependencies. Ist it possible to avoid setteing the presenter in the view via a setter method? The code looks something like this:

View:

public Class ViewImpl implements view {

private PresenterImpl presenter;
private User user;

@Inject
public ViewImpl(PresenterImpl presenter, User user) {
   super();
   this.presenter = presenter;
   this.user = user;
}

public void attach() {
   super.attach();

   presenter.fetchNames();

   showUser();
   }

public void setUser(User user) {
   this.user = user;
   }
}

Presenter:

public Class PresenterImpl implements Presenter {

private ViewImpl view;
private User user;

@Inject
public PresenterImpl(ViewImpl view, User user) {
   this.view = view;
   this.user = user;
}


public void fetchNames() {
   fetchFromDB();
   view.setUser(user);
}
}

Here I get the cyclic dependency. To avoid that I tried to use the Instance Interface and changed the presenter to this:

Presenter:

public Class PresenterImpl implements Presenter {

private ViewImpl view;
private Instance<ViewImpl> instanceView;
private User user;

@Inject
public PresenterImpl(Instance<ViewImpl> instanceView, User user) {
   this.instanceView = instanceView;
   this.user = user;

   bind();
}

public void bind() {
   this.view = instanceView.get();
}

public void fetchNames() {
   fetchFromDB();
   view.setUser(user);
}
}

But when I do that I get an java.lang.NoClassDefFoundError: org/jboss/weld/injection/Exceptions

Update: Here is the stack trace

[com.vaadin.Application] (http-localhost-127.0.0.1-8080-2) Terminal error:: java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) [rt.jar:1.7.0_05]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) [rt.jar:1.7.0_05]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) [rt.jar:1.7.0_05]
at java.lang.reflect.Method.invoke(Method.java:601) [rt.jar:1.7.0_05]
at com.vaadin.terminal.gwt.server.ServerRpcManager.applyInvocation(ServerRpcManager.java:141) [vaadin-7.0.0.alpha3.jar:7.0.0.alpha3]
at com.vaadin.terminal.gwt.server.ServerRpcManager.applyInvocation(ServerRpcManager.java:89) [vaadin-7.0.0.alpha3.jar:7.0.0.alpha3]
at com.vaadin.terminal.gwt.server.AbstractCommunicationManager.handleBurst(AbstractCommunicationManager.java:1660) [vaadin-7.0.0.alpha3.jar:7.0.0.alpha3]
at com.vaadin.terminal.gwt.server.AbstractCommunicationManager.handleVariables(AbstractCommunicationManager.java:1543) [vaadin-7.0.0.alpha3.jar:7.0.0.alpha3]
at com.vaadin.terminal.gwt.server.AbstractCommunicationManager.handleUidlRequest(AbstractCommunicationManager.java:577) [vaadin-7.0.0.alpha3.jar:7.0.0.alpha3]
at com.vaadin.terminal.gwt.server.AbstractApplicationServlet.service(AbstractApplicationServlet.java:461) [vaadin-7.0.0.alpha3.jar:7.0.0.alpha3]
at com.vaadin.terminal.gwt.server.AbstractApplicationServlet.service(AbstractApplicationServlet.java:350) [vaadin-7.0.0.alpha3.jar:7.0.0.alpha3]
at de.me.main.web.MEAppServlet.service(MEAppServlet.java:60) [classes:]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:847) [jboss-servlet-api_3.0_spec-1.0.0.Final.jar:1.0.0.Final]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:329) [jbossweb-7.0.13.Final.jar:]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248) [jbossweb-7.0.13.Final.jar:]
at org.jboss.weld.servlet.ConversationPropagationFilter.doFilter(ConversationPropagationFilter.java:62) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:280) [jbossweb-7.0.13.Final.jar:]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248) [jbossweb-7.0.13.Final.jar:]
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:275) [jbossweb-7.0.13.Final.jar:]
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:161) [jbossweb-7.0.13.Final.jar:]
at org.jboss.as.jpa.interceptor.WebNonTxEmCloserValve.invoke(WebNonTxEmCloserValve.java:50) [jboss-as-jpa-7.1.1.Final.jar:7.1.1.Final]
at org.jboss.as.web.security.SecurityContextAssociationValve.invoke(SecurityContextAssociationValve.java:153) [jboss-as-web-7.1.1.Final.jar:7.1.1.Final]
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:155) [jbossweb-7.0.13.Final.jar:]
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) [jbossweb-7.0.13.Final.jar:]
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) [jbossweb-7.0.13.Final.jar:]
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:368) [jbossweb-7.0.13.Final.jar:]
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:877) [jbossweb-7.0.13.Final.jar:]
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:671) [jbossweb-7.0.13.Final.jar:]
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:930) [jbossweb-7.0.13.Final.jar:]
at java.lang.Thread.run(Thread.java:722) [rt.jar:1.7.0_05]
Caused by: com.vaadin.event.ListenerMethod$MethodException: Invocation of method click in de.me.login.view.LoginViewImpl$1 failed.
at com.vaadin.event.ListenerMethod.receiveEvent(ListenerMethod.java:530) [vaadin-7.0.0.alpha3.jar:7.0.0.alpha3]
at com.vaadin.event.EventRouter.fireEvent(EventRouter.java:164) [vaadin-7.0.0.alpha3.jar:7.0.0.alpha3]
at com.vaadin.ui.AbstractComponent.fireEvent(AbstractComponent.java:1035) [vaadin-7.0.0.alpha3.jar:7.0.0.alpha3]
at com.vaadin.ui.Embedded$1.click(Embedded.java:97) [vaadin-7.0.0.alpha3.jar:7.0.0.alpha3]
... 30 more
Caused by: java.lang.NoClassDefFoundError: org/jboss/weld/injection/Exceptions
at org.jboss.weld.injection.ConstructorInjectionPoint.newInstance(ConstructorInjectionPoint.java:125) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.bean.ManagedBean.createInstance(ManagedBean.java:333) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.bean.ManagedBean$ManagedBeanInjectionTarget.produce(ManagedBean.java:200) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.bean.ManagedBean.create(ManagedBean.java:289) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.context.unbound.DependentContextImpl.get(DependentContextImpl.java:61) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.manager.BeanManagerImpl.getReference(BeanManagerImpl.java:616) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.manager.BeanManagerImpl.getReference(BeanManagerImpl.java:681) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.injection.ParameterInjectionPoint.getValueToInject(ParameterInjectionPoint.java:120) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.injection.ConstructorInjectionPoint.getParameterValues(ConstructorInjectionPoint.java:170) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.injection.ConstructorInjectionPoint.newInstance(ConstructorInjectionPoint.java:117) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.bean.ManagedBean.createInstance(ManagedBean.java:333) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.bean.ManagedBean$ManagedBeanInjectionTarget.produce(ManagedBean.java:200) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.bean.ManagedBean.create(ManagedBean.java:289) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.context.unbound.DependentContextImpl.get(DependentContextImpl.java:61) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.manager.BeanManagerImpl.getReference(BeanManagerImpl.java:616) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.manager.BeanManagerImpl.getReference(BeanManagerImpl.java:681) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.injection.ParameterInjectionPoint.getValueToInject(ParameterInjectionPoint.java:120) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.injection.ConstructorInjectionPoint.getParameterValues(ConstructorInjectionPoint.java:170) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.injection.ConstructorInjectionPoint.newInstance(ConstructorInjectionPoint.java:117) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.bean.ManagedBean.createInstance(ManagedBean.java:333) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.bean.ManagedBean$ManagedBeanInjectionTarget.produce(ManagedBean.java:200) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.bean.ManagedBean.create(ManagedBean.java:289) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.context.unbound.DependentContextImpl.get(DependentContextImpl.java:61) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.manager.BeanManagerImpl.getReference(BeanManagerImpl.java:616) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.manager.BeanManagerImpl.getReference(BeanManagerImpl.java:681) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.injection.ParameterInjectionPoint.getValueToInject(ParameterInjectionPoint.java:120) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.injection.ConstructorInjectionPoint.getParameterValues(ConstructorInjectionPoint.java:170) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.injection.ConstructorInjectionPoint.newInstance(ConstructorInjectionPoint.java:117) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.bean.ManagedBean.createInstance(ManagedBean.java:333) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.bean.ManagedBean$ManagedBeanInjectionTarget.produce(ManagedBean.java:200) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.bean.ManagedBean.create(ManagedBean.java:289) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.context.unbound.DependentContextImpl.get(DependentContextImpl.java:61) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.manager.BeanManagerImpl.getReference(BeanManagerImpl.java:616) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.manager.BeanManagerImpl.getReference(BeanManagerImpl.java:681) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.injection.ParameterInjectionPoint.getValueToInject(ParameterInjectionPoint.java:120) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.injection.ConstructorInjectionPoint.getParameterValues(ConstructorInjectionPoint.java:170) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.injection.ConstructorInjectionPoint.newInstance(ConstructorInjectionPoint.java:117) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.bean.ManagedBean.createInstance(ManagedBean.java:333) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.bean.ManagedBean$ManagedBeanInjectionTarget.produce(ManagedBean.java:200) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.bean.ManagedBean.create(ManagedBean.java:289) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.context.unbound.DependentContextImpl.get(DependentContextImpl.java:61) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.manager.BeanManagerImpl.getReference(BeanManagerImpl.java:616) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.manager.BeanManagerImpl.getReference(BeanManagerImpl.java:681) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.injection.ParameterInjectionPoint.getValueToInject(ParameterInjectionPoint.java:120) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.injection.ConstructorInjectionPoint.getParameterValues(ConstructorInjectionPoint.java:170) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.injection.ConstructorInjectionPoint.newInstance(ConstructorInjectionPoint.java:117) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.bean.ManagedBean.createInstance(ManagedBean.java:333) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.bean.ManagedBean$ManagedBeanInjectionTarget.produce(ManagedBean.java:200) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.bean.ManagedBean.create(ManagedBean.java:289) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.context.AbstractContext.get(AbstractContext.java:107) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.bean.proxy.ContextBeanInstance.getInstance(ContextBeanInstance.java:90) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at org.jboss.weld.bean.proxy.ProxyMethodHandler.invoke(ProxyMethodHandler.java:79) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
at de.me.main.layout.MainLayouter$Proxy$_$$_WeldClientProxy.go(MainLayouter$Proxy$_$$_WeldClientProxy.java) [MainService-0.0.5-SNAPSHOT.jar:]
at de.me.controller.MainController.showMainView(MainController.java:81) [MainService-0.0.5-SNAPSHOT.jar:]
at de.me.controller.MainController.access$0(MainController.java:80) [MainService-0.0.5-SNAPSHOT.jar:]
at de.me.controller.MainController$1.onLogin(MainController.java:48) [MainService-0.0.5-SNAPSHOT.jar:]
at de.me.presenter.LoginPresenterImpl.doLogin(LoginPresenterImpl.java:69) [UserManagement-0.0.5-SNAPSHOT.jar:]
at de.me.view.LoginViewImpl$1.click(LoginViewImpl.java:60) [UserManagement-0.0.5-SNAPSHOT.jar:]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) [rt.jar:1.7.0_05]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) [rt.jar:1.7.0_05]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) [rt.jar:1.7.0_05]
at java.lang.reflect.Method.invoke(Method.java:601) [rt.jar:1.7.0_05]
at com.vaadin.event.ListenerMethod.receiveEvent(ListenerMethod.java:510) [vaadin-7.0.0.alpha3.jar:7.0.0.alpha3]
... 33 more
Sebastian Basner
  • 515
  • 5
  • 11

4 Answers4

5

Try to move injection points from constructor to properties. So annotate properties with @Injection, not constructor. I think this way weld first creates instances of classes and only then injects dependencies. And replace your constructor with default.
If you annotate constructor weld needs to have instance of View when on creating Presenter, but to create View he needs Presenter. With default constructor and annotated properties it can create both View and Presenter and only then inject them to each other.

Nick
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Mikita Belahlazau
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5

I got it to work now. The hint from Nikita Beloglazov helped a lot because as I understand it the problem really is the moment when the instantiation is done. As I want to stay with the constructor injection I chose the second approach:

public Class PresenterImpl implements Presenter {

private ViewImpl view;
private Instance<ViewImpl> instanceView;
private User user;

@Inject
public PresenterImpl(Instance<ViewImpl> instanceView, User user) {
   this.instanceView = instanceView;
   this.user = user;

   bind();
}

public void bind() {
   this.view = instanceView.get();
}

public void fetchNames() {
   fetchFromDB();
   view.setUser(user);
}
}

To get this to work I have to inject only a proxy object at the time of constructor injection and get the real instance at the moment when the first action on the object is performed. This is the normal behavior of normal scoped beans. So I made the presenter and the view @SessionScoped and extended the interfaces from Serializable. Now the Constructor injection works and the ViewImpl is "lazy injected".

Sebastian Basner
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  • This approach really solve the circular dependency, but note that this exception is showing you that there's something wrong with your architecture. See [this answer](http://stackoverflow.com/a/15301179/1113510) of @nick – Moesio Apr 12 '13 at 14:45
0

It seems to me that Vaadin has nothing to do with the problem.

There may be (probably) a circular dependency injection problem but the problem lies in the ClassNotFoundException. What application server are you deploying to? Is it a full fledged Java EE 6 AS? If not, perhaps you're missing some libraries in your deployment.

Nicolas
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0

There's some approaches to solve circular dependency, but when this kind of exception is thrown note that could be something wrong with your architecture.

But consider see this answer

Community
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Moesio
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