I have a stateless EJB and two different SessionScoped managed beans.
e.g. EJB as follows -
@Stateless
public classs MyEjb implements MyEjbLocal {
@PersistentContext(unitName="myPU")
private EntityManager em;
and a managed bean -
@ManagedBean
@SessionScoped
public class MyBean1 implements Serializable {
@EJB
private MyEjbLocal myEjb;
and another managed bean -
@ManagedBean
@SessionScoped
public class MyBean2 implements Serilizable {
@EJB
private MyEjbLocal myEjb;
private List<MyEntity> entities;
public MyBean2() {
entities = myEjb.getAllEntities(); //this is where the problem is, myEjb is null
}
And I am using MyBean1 in page1 and MyBean2 in page2. The application starts with page1 and everything works perfect. But when I go to page2, I get exception saying that the container wasn't able to initialize MyBean2.
Why can't I inject 2 EJB's into 2 different managed beans that inject each other?
That's what I found when I searched and googled, and I think it's a different case, because he is injecting one managed bean into another.
I know I a possible solution could be to create two different EJBs. But I really want to know why it can not be done or if it can be done then what I might have done wrong.
I have already tested the myEjb.getAllEntities() method using the embeddable container, and it's working fine. MyEjb gets injected and I get all the entities.
Thank you.
Update: Stacktrace Sorry, this stack traces is really long.
SEVERE: com.sun.faces.mgbean.ManagedBeanCreationException: Cant instantiate class: com.vz.vit.dashboard.mb.ParamDTBean.
SEVERE: Error Rendering View[/dashboard.xhtml]
com.sun.faces.mgbean.ManagedBeanCreationException: Cant instantiate class: com.vz.vit.dashboard.mb.ParamDTBean.
at com.sun.faces.mgbean.BeanBuilder.newBeanInstance(BeanBuilder.java:193)
at com.sun.faces.mgbean.BeanBuilder.build(BeanBuilder.java:102)
at com.sun.faces.mgbean.BeanManager.createAndPush(BeanManager.java:409)
at com.sun.faces.mgbean.BeanManager.create(BeanManager.java:269)
at com.sun.faces.el.ManagedBeanELResolver.resolveBean(ManagedBeanELResolver.java:244)
at com.sun.faces.el.ManagedBeanELResolver.getValue(ManagedBeanELResolver.java:116)
at com.sun.faces.el.DemuxCompositeELResolver._getValue(DemuxCompositeELResolver.java:176)
at com.sun.faces.el.DemuxCompositeELResolver.getValue(DemuxCompositeELResolver.java:203)
at com.sun.el.parser.AstIdentifier.getValue(AstIdentifier.java:99)
at com.sun.el.parser.AstValue.getValue(AstValue.java:158)
at com.sun.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:219)
at com.sun.faces.facelets.el.TagValueExpression.getValue(TagValueExpression.java:109)
at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:194)
at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:182)
at javax.faces.component.UIData.getValue(UIData.java:731)
at org.primefaces.component.datatable.DataTable.getValue(DataTable.java:808)
at javax.faces.component.UIData.getDataModel(UIData.java:1798)
at javax.faces.component.UIData.setRowIndexWithoutRowStatePreserved(UIData.java:484)
at javax.faces.component.UIData.setRowIndex(UIData.java:473)
at javax.faces.component.UIData.visitTree(UIData.java:1401)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1600)
at javax.faces.component.UIForm.visitTree(UIForm.java:344)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1600)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1600)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1600)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1600)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1600)
at com.sun.faces.application.view.StateManagementStrategyImpl.saveView(StateManagementStrategyImpl.java:149)
at com.sun.faces.application.StateManagerImpl.saveView(StateManagerImpl.java:133)
at javax.faces.application.StateManager.getViewState(StateManager.java:553)
at com.sun.faces.context.PartialViewContextImpl.renderState(PartialViewContextImpl.java:409)
at com.sun.faces.context.PartialViewContextImpl.processPartial(PartialViewContextImpl.java:293)
at javax.faces.context.PartialViewContextWrapper.processPartial(PartialViewContextWrapper.java:183)
at javax.faces.component.UIViewRoot.encodeChildren(UIViewRoot.java:981)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1756)
at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:390)
at com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:131)
at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:121)
at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:139)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:410)
at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1534)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:281)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:655)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:595)
at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:98)
at com.sun.enterprise.web.PESessionLockingStandardPipeline.invoke(PESessionLockingStandardPipeline.java:91)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:162)
at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:326)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:227)
at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:170)
at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:822)
at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:719)
at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:1013)
at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:225)
at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:137)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:104)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:90)
at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:79)
at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:54)
at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:59)
at com.sun.grizzly.ContextTask.run(ContextTask.java:71)
at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:532)
at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:513)
at java.lang.Thread.run(Thread.java:662)
Caused by: java.lang.NullPointerException
at com.vz.vit.dashboard.mb.ParamDTBean.<init>(ParamDTBean.java:22)
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)
at com.sun.faces.mgbean.BeanBuilder.newBeanInstance(BeanBuilder.java:188)
... 65 more
SEVERE: com.sun.faces.mgbean.ManagedBeanCreationException: Cant instantiate class: com.vz.vit.dashboard.mb.ParamDTBean.
at com.sun.faces.mgbean.BeanBuilder.newBeanInstance(BeanBuilder.java:193)
at com.sun.faces.mgbean.BeanBuilder.build(BeanBuilder.java:102)
at com.sun.faces.mgbean.BeanManager.createAndPush(BeanManager.java:409)
at com.sun.faces.mgbean.BeanManager.create(BeanManager.java:269)
at com.sun.faces.el.ManagedBeanELResolver.resolveBean(ManagedBeanELResolver.java:244)
at com.sun.faces.el.ManagedBeanELResolver.getValue(ManagedBeanELResolver.java:116)
at com.sun.faces.el.DemuxCompositeELResolver._getValue(DemuxCompositeELResolver.java:176)
at com.sun.faces.el.DemuxCompositeELResolver.getValue(DemuxCompositeELResolver.java:203)
at com.sun.el.parser.AstIdentifier.getValue(AstIdentifier.java:99)
at com.sun.el.parser.AstValue.getValue(AstValue.java:158)
at com.sun.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:219)
at com.sun.faces.facelets.el.TagValueExpression.getValue(TagValueExpression.java:109)
at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:194)
at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:182)
at javax.faces.component.UIData.getValue(UIData.java:731)
at org.primefaces.component.datatable.DataTable.getValue(DataTable.java:808)
at javax.faces.component.UIData.getDataModel(UIData.java:1798)
at javax.faces.component.UIData.setRowIndexWithoutRowStatePreserved(UIData.java:484)
at javax.faces.component.UIData.setRowIndex(UIData.java:473)
at javax.faces.component.UIData.visitTree(UIData.java:1401)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1600)
at javax.faces.component.UIForm.visitTree(UIForm.java:344)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1600)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1600)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1600)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1600)
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1600)
at com.sun.faces.application.view.StateManagementStrategyImpl.saveView(StateManagementStrategyImpl.java:149)
at com.sun.faces.application.StateManagerImpl.saveView(StateManagerImpl.java:133)
at javax.faces.application.StateManager.getViewState(StateManager.java:553)
at com.sun.faces.context.PartialViewContextImpl.renderState(PartialViewContextImpl.java:409)
at com.sun.faces.context.PartialViewContextImpl.processPartial(PartialViewContextImpl.java:293)
at javax.faces.context.PartialViewContextWrapper.processPartial(PartialViewContextWrapper.java:183)
at javax.faces.component.UIViewRoot.encodeChildren(UIViewRoot.java:981)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1756)
at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:390)
at com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:131)
at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:121)
at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:139)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:410)
at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1534)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:281)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:655)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:595)
at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:98)
at com.sun.enterprise.web.PESessionLockingStandardPipeline.invoke(PESessionLockingStandardPipeline.java:91)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:162)
at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:326)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:227)
at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:170)
at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:822)
at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:719)
at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:1013)
at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:225)
at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:137)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:104)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:90)
at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:79)
at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:54)
at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:59)
at com.sun.grizzly.ContextTask.run(ContextTask.java:71)
at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:532)
at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:513)
at java.lang.Thread.run(Thread.java:662)
Caused by: java.lang.NullPointerException
at com.vz.vit.dashboard.mb.ParamDTBean.<init>(ParamDTBean.java:22)
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)
at com.sun.faces.mgbean.BeanBuilder.newBeanInstance(BeanBuilder.java:188)
... 65 more
WARNING: StandardWrapperValve[Faces Servlet]: PWC1406: Servlet.service() for servlet Faces Servlet threw exception
java.lang.IllegalStateException: CDATA tags may not nest
at com.sun.faces.renderkit.html_basic.HtmlResponseWriter.startCDATA(HtmlResponseWriter.java:630)
at javax.faces.context.ResponseWriterWrapper.startCDATA(ResponseWriterWrapper.java:172)
at javax.faces.context.PartialResponseWriter.startError(PartialResponseWriter.java:342)
at org.primefaces.context.PrimePartialResponseWriter.startError(PrimePartialResponseWriter.java:108)
at com.sun.faces.context.AjaxExceptionHandlerImpl.handlePartialResponseError(AjaxExceptionHandlerImpl.java:201)
at com.sun.faces.context.AjaxExceptionHandlerImpl.handle(AjaxExceptionHandlerImpl.java:124)
at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:119)
at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:139)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:410)
at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1534)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:281)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:655)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:595)
at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:98)
at com.sun.enterprise.web.PESessionLockingStandardPipeline.invoke(PESessionLockingStandardPipeline.java:91)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:162)
at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:326)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:227)
at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:170)
at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:822)
at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:719)
at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:1013)
at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:225)
at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:137)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:104)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:90)
at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:79)
at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:54)
at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:59)
at com.sun.grizzly.ContextTask.run(ContextTask.java:71)
at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:532)
at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:513)
at java.lang.Thread.run(Thread.java:662)
It was my mistake, I was trying to use the ejb in the constructor as follows -
public MyBean2() {
entities = myEjb.getAllEntities(); //this is where the problem is, myEjb is null
}
Now, I know that the ejb is injected only after the container is done instantiating the managed bean.
Now I have.
@PostConstrut
private void init() {
entities = myEjb.getAllEntities();
}
来源：https://stackoverflow.com/questions/6529865/injecting-same-ejb-into-two-different-managed-beans-not-working