Error - javax.el.ELException: /rss.xhtml @20,69 value="#{revistaAction.initRss()}": javax.persistence.NonUniqueResultException: result returns 2 elements

javax.el.ELException: /rss.xhtml @20,69 value="#{revistaAction.initRss()}": javax.persistence.NonUniqueResultException: result returns 2 elements

javax.faces.el.EvaluationException: javax.el.ELException: /rss.xhtml @20,69 value="#{revistaAction.initRss()}": javax.persistence.NonUniqueResultException: result returns 2 elements
	at javax.faces.component.ValueBindingValueExpressionAdapter.getValue(ValueBindingValueExpressionAdapter.java:117)
	at com.sun.facelets.component.UIRepeat.getValue(UIRepeat.java:143)
	at com.sun.facelets.component.UIRepeat.getDataModel(UIRepeat.java:121)
	at com.sun.facelets.component.UIRepeat.setIndex(UIRepeat.java:305)
	at com.sun.facelets.component.UIRepeat.process(UIRepeat.java:333)
	at com.sun.facelets.component.UIRepeat.encodeChildren(UIRepeat.java:617)
	at javax.faces.component.UIComponent.encodeAll(UIComponent.java:930)
	at javax.faces.component.UIComponent.encodeAll(UIComponent.java:933)
	at com.sun.facelets.FaceletViewHandler.renderView(FaceletViewHandler.java:592)
	at org.ajax4jsf.application.ViewHandlerWrapper.renderView(ViewHandlerWrapper.java:100)
	at org.ajax4jsf.application.AjaxViewHandler.renderView(AjaxViewHandler.java:176)
	at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:110)
	at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:100)
	at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:139)
	at javax.faces.webapp.FacesServlet.service(FacesServlet.java:266)
	at org.apache.catalina.core.ApplicationFilterChain.servletService(ApplicationFilterChain.java:427)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:333)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214)
	at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:83)
	at org.jboss.seam.web.MultipartFilter.doFilter(MultipartFilter.java:85)
	at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
	at org.jboss.seam.web.ExceptionFilter.doFilter(ExceptionFilter.java:64)
	at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
	at org.jboss.seam.web.RedirectFilter.doFilter(RedirectFilter.java:45)
	at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
	at org.ajax4jsf.webapp.BaseXMLFilter.doXmlFilter(BaseXMLFilter.java:178)
	at org.ajax4jsf.webapp.BaseFilter.handleRequest(BaseFilter.java:290)
	at org.ajax4jsf.webapp.BaseFilter.processUploadsAndHandleRequest(BaseFilter.java:390)
	at org.ajax4jsf.webapp.BaseFilter.doFilter(BaseFilter.java:517)
	at org.jboss.seam.web.Ajax4jsfFilter.doFilter(Ajax4jsfFilter.java:60)
	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.debug.hot.HotDeployFilter.doFilter(HotDeployFilter.java:68)
	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:246)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:313)
	at org.apache.catalina.core.StandardContextValve.invokeInternal(StandardContextValve.java:287)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:218)
	at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:648)
	at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:593)
	at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:94)
	at com.sun.enterprise.web.PESessionLockingStandardPipeline.invoke(PESessionLockingStandardPipeline.java:98)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:222)
	at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:648)
	at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:593)
	at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:587)
	at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:1093)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:166)
	at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:648)
	at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:593)
	at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:587)
	at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:1093)
	at org.apache.coyote.tomcat5.CoyoteAdapter.service(CoyoteAdapter.java:291)
	at org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:200)
	at org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:283)
	at org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:773)
	at org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket.java:703)
	at org.apache.jk.common.ChannelSocket$SocketConnection.runIt(ChannelSocket.java:895)
	at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:682)
	at java.lang.Thread.run(Thread.java:662)
Caused by: javax.el.ELException: /rss.xhtml @20,69 value="#{revistaAction.initRss()}": javax.persistence.NonUniqueResultException: result returns 2 elements
	at com.sun.facelets.el.TagValueExpression.getValue(TagValueExpression.java:76)
	at javax.faces.component.ValueBindingValueExpressionAdapter.getValue(ValueBindingValueExpressionAdapter.java:113)
	... 62 more
Caused by: javax.persistence.NonUniqueResultException: result returns 2 elements
	at org.hibernate.ejb.QueryImpl.getSingleResult(QueryImpl.java:89)
	at org.jboss.seam.framework.EntityQuery.initSingleResult(EntityQuery.java:102)
	at org.jboss.seam.framework.EntityQuery.getSingleResult(EntityQuery.java:93)
	at rdg.action.RevistaAction.initRss(RevistaAction.java:854)
	at sun.reflect.GeneratedMethodAccessor2817.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at java.lang.reflect.Method.invoke(Method.java:597)
	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.core.BijectionInterceptor.aroundInvoke(BijectionInterceptor.java:46)
	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.core.SynchronizationInterceptor.aroundInvoke(SynchronizationInterceptor.java:32)
	at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68)
	at org.jboss.seam.intercept.RootInterceptor.invoke(RootInterceptor.java:107)
	at org.jboss.seam.intercept.JavaBeanInterceptor.interceptInvocation(JavaBeanInterceptor.java:166)
	at org.jboss.seam.intercept.JavaBeanInterceptor.invoke(JavaBeanInterceptor.java:102)
	at rdg.action.RevistaAction_$$_javassist_2.initRss(RevistaAction_$$_javassist_2.java)
	at sun.reflect.GeneratedMethodAccessor2816.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at java.lang.reflect.Method.invoke(Method.java:597)
	at org.jboss.el.util.ReflectionUtil.invokeMethod(ReflectionUtil.java:329)
	at org.jboss.el.util.ReflectionUtil.invokeMethod(ReflectionUtil.java:274)
	at org.jboss.el.parser.AstMethodSuffix.getValue(AstMethodSuffix.java:59)
	at org.jboss.el.parser.AstValue.getValue(AstValue.java:67)
	at org.jboss.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:186)
	at com.sun.facelets.el.TagValueExpression.getValue(TagValueExpression.java:71)
	... 63 more

<AjaxViewRoot id="_viewRoot" immediate="false" locale="en" renderKitId="HTML_BASIC" renderRegionOnly="false" rendered="true" selfRendered="false" submitted="false" transient="false" viewId="/rss.xhtml">
<!DOCTYPE composition PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd" >
<rss version="2.0">
<channel>
            <title>El més nou a Revista de Girona</title>
            <link>http://www.revistadegirona.cat/</link>
            <image>
                <url>http://www.revistadegirona.cat/rdg/img/logo_mail.gif</url>
                <title>Revista de Girona</title>
                <link>http://www.revistadegirona.cat/</link>
            </image>
            <description>Entrades recents a Revista de Girona</description>
            <language>ca-es</language>
<UIRepeat id="j_id3" offset="0" rendered="true" size="-1" transient="false" var="art">
<item>
                    <title>#{art.article_web_titol}</title>
                    <link>http://www.revistadegirona.cat/</link>
                    <author>
                        <name>#{art.article_web_autor}</name>
                    </author>
                    <description>
                        #{art.article_web_text}
                    </description>
                </item>
</UIRepeat>
<generator>Revista de Girona RSS Engine</generator>
        </channel>
</rss>
</AjaxViewRoot>

05/02/2012 03:09:22 - Generated by Facelets

Name	Value
articles	org.jboss.seam.jsf.ListDataModel@eeda16
articlesPortada	org.jboss.seam.jsf.ListDataModel@12fed4b
arxiu	org.jboss.seam.jsf.ListDataModel@183f64f
galeries	org.jboss.seam.jsf.ListDataModel@9fc792
havePromo	true
nearPageOk	false
nextPageOk	true
nom_gal	No hi han galeries
numRevista
opinioAction	rdg.action.OpinioAction@1e747b0
quiosc	org.jboss.seam.jsf.ListDataModel@113b56a
quioscAction	rdg.action.QuioscAction@eb5737
revExists	false
revistaAction	rdg.action.RevistaAction@ab0354
revistes_anteriors	org.jboss.seam.jsf.ListDataModel@167b88f
sumari	org.jboss.seam.jsf.ListDataModel@85c35e
tabClasse	mario_martinez
ultimaRevista_any	2012
ultimaRevista_id	270
videos2	org.jboss.seam.jsf.ListDataModel@1dd52a3

Name	Value
revistaGironaEntityManagerFactory	org.jboss.seam.persistence.EntityManagerFactory@129a2ad
securityRules	org.jboss.seam.drools.RuleBase@772b39

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