selectOneMenu - NPE

[w17chm4n]

I`m getting NPE when using selectOneMenu, why is that ?

view

<h:selectOneMenu value="#{questionCategory}" required="true">
 <s:selectItems value="#{questionCategoryList}" var="category" label="#{category.categoryName}"/>
 <s:convertEntity/>
 </h:selectOneMenu>

components.xml

<components xmlns="http://jboss.com/products/seam/components"
 xmlns:core="http://jboss.com/products/seam/core"
 xmlns:security="http://jboss.com/products/seam/security"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation=
 "http://jboss.com/products/seam/core http://jboss.com/products/seam/core-1.2.xsd
 http://jboss.com/products/seam/security http://jboss.com/products/seam/security-1.2.xsd
http://jboss.com/products/seam/components http://jboss.com/products/seam/components-1.2.xsd">

 <component name="org.jboss.seam.core.init">
 <property name="debug">true</property>
 <property name="myFacesLifecycleBug">true</property>
 <property name="jndiPattern">Inquisitor/#{ejbName}/local</property>
 </component>

 <component class="org.jboss.seam.web.MultipartFilter">
 <property name="createTempFiles">true</property>
 <property name="maxRequestSize">1000000</property>
 </component>

 <core:managed-persistence-context name="entityManager" auto-create="true" persistence-unit-jndi-name="java:/EntityManagerFactory"/>
</components>

[w17chm4n]

Exception

10:40:36,766 ERROR [STDERR] Nov 19, 2007 10:40:36 AM com.sun.facelets.FaceletViewHandler handleRenderException
SEVERE: Error Rendering View[/question.xhtml]
java.lang.NullPointerException
 at org.jboss.seam.ui.converter.EntityConverterStore.getEntityManager(EntityConverterStore.java:81)
 at org.jboss.seam.ui.converter.EntityConverterStore.put(EntityConverterStore.java:60)
 at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
 at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
 at java.lang.reflect.Method.invoke(Method.java:585)
 at org.jboss.seam.util.Reflections.invoke(Reflections.java:21)
 at org.jboss.seam.intercept.RootInvocationContext.proceed(RootInvocationContext.java:31)
 at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:56)
 at org.jboss.seam.transaction.RollbackInterceptor.aroundInvoke(RollbackInterceptor.java:31)
 at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68)
 at org.jboss.seam.transaction.TransactionInterceptor$1.work(TransactionInterceptor.java:38)
 at org.jboss.seam.util.Work.workInTransaction(Work.java:40)
 at org.jboss.seam.transaction.TransactionInterceptor.aroundInvoke(TransactionInterceptor.java:32)
 at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68)
 at org.jboss.seam.core.MethodContextInterceptor.aroundInvoke(MethodContextInterceptor.java:42)
 at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68)
 at org.jboss.seam.intercept.RootInterceptor.invoke(RootInterceptor.java:106)
 at org.jboss.seam.intercept.JavaBeanInterceptor.interceptInvocation(JavaBeanInterceptor.java:155)
 at org.jboss.seam.intercept.JavaBeanInterceptor.invoke(JavaBeanInterceptor.java:91)
 at org.jboss.seam.ui.converter.EntityConverterStore_$$_javassist_0.put(EntityConverterStore_$$_javassist_0.java)
 at org.jboss.seam.ui.converter.EntityConverter.getAsString(EntityConverter.java:67)
 at com.sun.faces.renderkit.html_basic.HtmlBasicRenderer.getFormattedValue(HtmlBasicRenderer.java:469)
 at com.sun.faces.renderkit.html_basic.MenuRenderer.renderOption(MenuRenderer.java:502)
 at com.sun.faces.renderkit.html_basic.MenuRenderer.renderOptions(MenuRenderer.java:757)
 at com.sun.faces.renderkit.html_basic.MenuRenderer.renderSelect(MenuRenderer.java:811)
 at com.sun.faces.renderkit.html_basic.MenuRenderer.encodeEnd(MenuRenderer.java:335)
 at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:836)
 at javax.faces.component.UIComponent.encodeAll(UIComponent.java:896)
 at javax.faces.render.Renderer.encodeChildren(Renderer.java:137)
 at javax.faces.component.UIComponentBase.encodeChildren(UIComponentBase.java:812)
 at javax.faces.component.UIComponent.encodeAll(UIComponent.java:886)
 at javax.faces.component.UIComponent.encodeAll(UIComponent.java:892)
 at com.sun.facelets.FaceletViewHandler.renderView(FaceletViewHandler.java:592)
 at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:106)
 at com.sun.faces.lifecycle.LifecycleImpl.phase(LifecycleImpl.java:251)
 at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:144)
 at javax.faces.webapp.FacesServlet.service(FacesServlet.java:245)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
 at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:83)
 at org.jboss.seam.debug.hot.HotDeployFilter.doFilter(HotDeployFilter.java:68)
 at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
 at org.jboss.seam.web.LoggingFilter.doFilter(LoggingFilter.java:58)
 at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
 at org.jboss.seam.web.MultipartFilter.doFilter(MultipartFilter.java:85)
 at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
 at org.jboss.seam.web.ExceptionFilter.doFilter(ExceptionFilter.java:64)
 at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
 at org.jboss.seam.web.RedirectFilter.doFilter(RedirectFilter.java:44)
 at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
 at org.jboss.seam.servlet.SeamFilter.doFilter(SeamFilter.java:158)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
 at org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
 at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:230)
 at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
 at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:179)
 at org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:84)
 at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
 at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
 at org.jboss.web.tomcat.service.jca.CachedConnectionValve.invoke(CachedConnectionValve.java:157)
 at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
 at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:262)
 at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
 at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
 at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:446)
 at java.lang.Thread.run(Thread.java:595)

[marius.oancea]

Please post the whole NPE exception.

Are you sure questionCategoryList is outjected?

[marius.oancea]

Ah. I posted my message before you posted the exception.

Anyway: please make sue you are using the entityManager (and is named entityManager). This seems correct according to your posted XML.

Your entity has to have a @Id. Make sure of that.

NPE seems to be at
EntityIdentifier key = new EntityIdentifier(entity, getEntityManager());

Eventually make a brackpoint here and see what is null.

[pmuir]

Which version of Seam?

[w17chm4n]

@Pete
Seam 2.0.0.GA

@Marius
Yes I`m sure that questionCategoryList is outjected. Anyway, this code works on Seam 1.2.1.GA...

questionCategory entity

@Entity
@Scope(ScopeType.EVENT)
@Name("questionCategory")
@Table(name="QuestionCategories")
public class QuestionCategory implements Serializable {

 @Id @GeneratedValue
 private Long id;

 @NotNull @Length(min=3, max=100)
 private String categoryName;

 @OneToMany @JoinColumn(name="category_id")
 private List<Question> questionList;

 @Temporal(value = TemporalType.TIMESTAMP)
 private Date created;

 @Override
 public boolean equals(Object obj) {
 if (!(obj instanceof QuestionCategory) || this.id == null) {
 return false;
 }

 return this.id.equals(((QuestionCategory)obj).getId());
 }

 public QuestionCategory() {
 this.questionList = new ArrayList<Question>();
 }

 public QuestionCategory(String categoryName) {
 this.categoryName = categoryName;
 this.questionList = new ArrayList<Question>();
 }

 public Long getId() {
 return id;
 }

 public void setId(Long id) {
 this.id = id;
 }

 public String getCategoryName() {
 return categoryName;
 }

 public void setCategoryName(String categoryName) {
 this.categoryName = categoryName;
 }

 public List<Question> getQuestionList() {
 return questionList;
 }

 public void setQuestionList(List<Question> questionList) {
 this.questionList = questionList;
 }

 public Date getCreated() {
 return created;
 }

 public void setCreated(Date created) {
 this.created = created;
 }
}

[dhinojosa]

1. What does the bean that generates questionCategoryList look like?

[w17chm4n]

@Stateful
@Scope(ScopeType.SESSION)
@Name("QuestionCategoryController")
public class QuestionCategoryControllerBean implements QuestionCategoryController {

 @Logger
 private Log log;

 @In(create = true)
 private QuestionCategoryManager questionCategoryManager;

 @DataModel
 private List<QuestionCategory> questionCategoryList;

 @In(create = true)
 @DataModelSelection
 private QuestionCategory questionCategory;

 public void addCategory() {
 log.info("Adding category [#{questionCategory.categoryName}]");
 questionCategoryManager.addCategory(questionCategory);
 getAllQuestionsCategories();
 }

 public void removeCategory() {
 questionCategoryList.remove(questionCategory);
 questionCategoryManager.removeCategory(questionCategory);
 questionCategory = null;
 getAllQuestionsCategories();
 }

 @Factory(value="questionCategoryList")
 public void getAllQuestionsCategories() {
 questionCategoryList = questionCategoryManager.getAllQuestionCategories();
 }

 @Remove @Destroy
 public void destroy() {}
 }

Session context

 QuestionCategoryController
QuestionController
facelets.ui.DebugOutput
javax.faces.request.charset
org.jboss.seam.core.conversationEntries
org.jboss.seam.international.localeSelector
org.jboss.seam.international.timeZoneSelector
org.jboss.seam.security.identity
org.jboss.seam.web.session
questionCategoryList

[w17chm4n]

anybody ?

[pmuir]

If you can create a runnable example and provide steps to reproduce please put an issue into JIRA so I can take a look.