我有一个@Embeddable包含属性的类@Enumerated。我想@Enumerated在 selectOneMenu primefaces 中显示此属性的值。问题是当我尝试显示我的页面时，它返回一个@Enumeratednull 异常，我不知道如何解决这个问题。
枚举
public enum EstadosDoBrasil {
AC,
AL,
AM,
AP,
BA,
CE,
DF,
ES,
FN,
GO,
MA,
MG,
MS,
MT,
PA,
PB,
PE,
PI,
PR,
RJ,
RN,
RO,
RR,
RS,
SC,
SE,
SP,
TO;
}
可嵌入
@Embeddable
public class Endereco {
@NotNull @Size(min=5, message="Informe o endereço")
private String endereco;
@NotNull
private Integer numero;
private String complemento;
@NotNull @Size(min=5, message="Informe a cidade")
private String cidade;
@NotNull @Size(min=3, message="Informe o bairro")
private String bairro;
private String cep;
@Enumerated(EnumType.STRING)
private EstadosDoBrasil uf;
//gets sets
实体域
@Entity
@NamedQueries({
@NamedQuery(name=UnidadeEscolar.FIND_ALL, query="SELECT ue FROM UnidadeEscolar ue")
})
public class UnidadeEscolar implements Serializable{
private static final long serialVersionUID = 1L;
public static final String FIND_ALL = "unidadeEscolar.findAll";
@Id @GeneratedValue(strategy=GenerationType.AUTO)
private Long id;
@NotNull @Size(min=5, message="Informe o nome da unidade escolar")
private String nome;
private String departamento;
@Embedded
private Endereco endereco;
public UnidadeEscolar() {
endereco = new Endereco();
}
托管豆
@ManagedBean
@ViewScoped
public class UnidadeEscolarMB {
private UnidadeEscolar bean;
private GenericDAO<UnidadeEscolar> dao;
private List<UnidadeEscolar> unidades = null;
/** insere uma nova unidade escolar */
public void prepareCreate(){
bean = new UnidadeEscolar();
}
/** retorna o objeto */
public UnidadeEscolar getBean() {
return bean;
}
/** define o objeto */
public void setBean(UnidadeEscolar bean) {
this.bean = bean;
}
//enum values
public EstadosDoBrasil[] getUF(){
return EstadosDoBrasil.values();
}
}
Xhtml
<p:outputLabel value="U.F"/>
<p:selectOneMenu value="#{unidadeEscolarMB.bean.endereco.uf}">
<f:selectItems value="#{unidadeEscolarMB.UF}" var="uf"
itemLabel="#{uf}" itemValue="#{uf}"/>
</p:selectOneMenu>
例外
1100: /unidade_escolar/create.xhtml @75,80 value="#{unidadeEscolarMB.bean.endereco.uf}": Target Unreachable, 'bean' returned null
javax.el.PropertyNotFoundException: /unidade_escolar/create.xhtml @75,80 value="#{unidadeEscolarMB.bean.endereco.uf}": Target Unreachable, 'bean' returned null
at com.sun.faces.facelets.el.TagValueExpression.getType(TagValueExpression.java:100)
at org.primefaces.renderkit.InputRenderer.findImplicitConverter(InputRenderer.java:172)
at org.primefaces.renderkit.InputRenderer.getOptionAsString(InputRenderer.java:158)
at org.primefaces.component.selectonemenu.SelectOneMenuRenderer.encodeOption(SelectOneMenuRenderer.java:345)
at org.primefaces.component.selectonemenu.SelectOneMenuRenderer.encodeSelectItems(SelectOneMenuRenderer.java:331)
at org.primefaces.component.selectonemenu.SelectOneMenuRenderer.encodeInput(SelectOneMenuRenderer.java:114)
at org.primefaces.component.selectonemenu.SelectOneMenuRenderer.encodeMarkup(SelectOneMenuRenderer.java:91)
at org.primefaces.component.selectonemenu.SelectOneMenuRenderer.encodeEnd(SelectOneMenuRenderer.java:65)
at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:924)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1863)
at org.primefaces.component.panelgrid.PanelGridRenderer.encodeDynamicBody(PanelGridRenderer.java:92)
at org.primefaces.component.panelgrid.PanelGridRenderer.encodeBody(PanelGridRenderer.java:60)
at org.primefaces.component.panelgrid.PanelGridRenderer.encodeEnd(PanelGridRenderer.java:49)
at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:924)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1863)
at javax.faces.render.Renderer.encodeChildren(Renderer.java:176)
at javax.faces.component.UIComponentBase.encodeChildren(UIComponentBase.java:894)
at org.primefaces.renderkit.CoreRenderer.renderChild(CoreRenderer.java:70)
at org.primefaces.renderkit.CoreRenderer.renderChildren(CoreRenderer.java:57)
at org.primefaces.component.dialog.DialogRenderer.encodeContent(DialogRenderer.java:184)
at org.primefaces.component.dialog.DialogRenderer.encodeMarkup(DialogRenderer.java:113)
at org.primefaces.component.dialog.DialogRenderer.encodeEnd(DialogRenderer.java:47)
at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:924)
at org.primefaces.renderkit.CoreRenderer.renderChild(CoreRenderer.java:74)
at org.primefaces.renderkit.CoreRenderer.renderChildren(CoreRenderer.java:57)
at org.primefaces.renderkit.CoreRenderer.renderChild(CoreRenderer.java:72)
at org.primefaces.renderkit.CoreRenderer.renderChildren(CoreRenderer.java:57)
at org.primefaces.component.dialog.DialogRenderer.encodeContent(DialogRenderer.java:184)
at org.primefaces.component.dialog.DialogRenderer.encodeMarkup(DialogRenderer.java:113)
at org.primefaces.component.dialog.DialogRenderer.encodeEnd(DialogRenderer.java:47)
at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:924)
at org.primefaces.renderkit.CoreRenderer.renderChild(CoreRenderer.java:74)
at org.primefaces.renderkit.CoreRenderer.renderChildren(CoreRenderer.java:57)
at org.primefaces.renderkit.CoreRenderer.renderChild(CoreRenderer.java:72)
at org.primefaces.renderkit.CoreRenderer.renderChildren(CoreRenderer.java:57)
at org.primefaces.component.layout.LayoutUnitRenderer.encodeEnd(LayoutUnitRenderer.java:51)
at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:924)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1863)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1859)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1859)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1859)
at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:443)
at com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:131)
at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:120)
at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:219)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:647)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:291)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:503)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:136)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:610)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:526)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1078)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:655)
at org.apache.coyote.http11.Http11NioProtocol$Http11ConnectionHandler.process(Http11NioProtocol.java:222)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1566)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1523)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Unknown Source)
Caused by: javax.el.PropertyNotFoundException: Target Unreachable, 'bean' returned null
at org.apache.el.parser.AstValue.getTarget(AstValue.java:122)
at org.apache.el.parser.AstValue.getType(AstValue.java:56)
at org.apache.el.ValueExpressionImpl.getType(ValueExpressionImpl.java:171)
at com.sun.faces.facelets.el.TagValueExpression.getType(TagValueExpression.java:98)
... 68 more