[RESOLVIDO]Listagem JSF - aparece em branco

Pessoal, peguei um exemplo de listagem em JSF, so que contem registro no banco de dados só que a listagem aparece em branco. segue em anexo e o meu codigo fonte.

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
      xmlns:h="http://java.sun.com/jsf/html"
      xmlns:f="http://java.sun.com/jsf/core"
      xmlns:ui="http://java.sun.com/jsf/facelets">
<h:head>
	<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1" />
	<title>Cadastro</title>
</h:head>
<h:body>
      <h:form>
         <h:messages />
         <h:dataTable value = "#{usuarioBean.lista}" var="usuario" rules="rows" cellpadding="7">
             <f:facet name="caption">
             teste teste teste
             </f:facet>
             
            <f:facet name="header">Listagem de usuario Cadastrados</f:facet>
            <f:facet name="footer">Final da Listagem</f:facet>
            
            <h:column>
               <f:facet name="header">identificação</f:facet>
               #{usuario.idusuario}
            </h:column>

            <h:column>
                <h:commandLink action="#{usuarioBean.active}">
                	<h:graphicImage library="img" name="estatus_#{usuario.estatus}"></h:graphicImage>
                </h:commandLink>
            </h:column>

            <h:column>                
                	<h:graphicImage library="img" name="#{usuario.idioma}"></h:graphicImage>
                
            </h:column>


            <h:column>
               <f:facet name="header">Nome</f:facet>
               #{usuario.nome}
            </h:column>
         
            <h:column>
               <f:facet name="header">E-mail</f:facet>
               #{usuario.email}
            </h:column>
         
            <h:column>
            <f:facet name="header">Editar</f:facet>
              <h:commandLink action="#{usuarioBean.edit}">
                 <h:graphicImage library="img" name="edit.png" style="border:0"></h:graphicImage>
                 <f:setPropertyActionListener target="#{usuarioBean.usuario}" value="#{usuario}"></f:setPropertyActionListener>
              
              </h:commandLink>
            </h:column>    
            
            
            <h:column>
              <h:commandLink action="#{usuarioBean.delete}">
                 <h:graphicImage library="img" name="delete.png" style="border:0"></h:graphicImage>
                 <f:setPropertyActionListener target="#{usuarioBean.usuario}" value="#{usuario}"></f:setPropertyActionListener>
              
              </h:commandLink>
            </h:column>  
                             
         </h:dataTable>
         
      </h:form>

</h:body>

</html>



package bean;

import java.util.List;

import javax.faces.application.FacesMessage;
import javax.faces.bean.ManagedBean;
import javax.faces.bean.RequestScoped;
import javax.faces.context.FacesContext;

import dao.UsuarioRN;

import banco.BancoDeClientes;

import modelo.Usuario;

@ManagedBean(name = "usuarioBean")
@RequestScoped
public class UsuarioBean {
	
	private Usuario usuario = new Usuario();
	BancoDeClientes bdc = new BancoDeClientes();
	private String confirmarsenha;
	private List<Usuario> lista;
	
	
	public String salvar(){
		FacesContext context = FacesContext.getCurrentInstance();
		String senha = usuario.getSenha();
		if (! senha.equals(confirmarsenha)){
			FacesMessage facesMessage = new FacesMessage("Confirmar");
			context.addMessage(null, facesMessage);
			return null;
		}
		bdc.salvaruser(usuario);
		return "UsuarioCadastrado";
	}
	
	public List<Usuario> getLista(){
		if (lista == null) {
			 UsuarioRN usuarioRN = new UsuarioRN();
			 lista = usuarioRN.listar();	 
		}
		return lista;
	}
	

}


package dao;

import java.util.List;

import modelo.Usuario;



public class UsuarioRN {
	private UsuarioDAO usuarioDAO;
	
	public List<Usuario> listar() {
		return usuarioDAO.listar();
	}


}

package dao;
import java.util.List;

import modelo.Usuario;
public interface UsuarioDAO {
	public List<Usuario> listar();
}


você esqueceu de passar
como que você está obtendo a lista

e outra teste isso dentro desse método

[code]public List getLista(){
if (lista == null) {
UsuarioRN usuarioRN = new UsuarioRN();
lista = usuarioRN.listar();

System.out.println("Tamanho da lista : " + lista.size());

    }  
    return lista;  
}  [/code]

se o valor for nulo é pq não tem erro na view e sim la no dao
que não esta trazendo nada

Pessoal,

esta dando o erro abaixo

RAVE: Error Rendering View[/listagem.xhtml]
javax.el.ELException: /listagem.xhtml @13,97 value="#{usuarioBean.lista}": Error reading ‘lista’ on type bean.UsuarioBean
at com.sun.faces.facelets.el.TagValueExpression.getValue(TagValueExpression.java:114)
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 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 com.sun.faces.renderkit.html_basic.TableRenderer.encodeBegin(TableRenderer.java:81)
at javax.faces.component.UIComponentBase.encodeBegin(UIComponentBase.java:820)
at javax.faces.component.UIData.encodeBegin(UIData.java:1118)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1754)
at javax.faces.render.Renderer.encodeChildren(Renderer.java:168)
at javax.faces.component.UIComponentBase.encodeChildren(UIComponentBase.java:845)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1756)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1759)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1759)
at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:401)
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.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:304)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:240)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:164)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:462)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:164)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:562)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:395)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:250)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:188)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:166)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:302)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.NullPointerException
at dao.UsuarioRN.listar(UsuarioRN.java:13)
at bean.UsuarioBean.getLista(UsuarioBean.java:41)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at javax.el.BeanELResolver.getValue(BeanELResolver.java:87)
at com.sun.faces.el.DemuxCompositeELResolver._getValue(DemuxCompositeELResolver.java:176)
at com.sun.faces.el.DemuxCompositeELResolver.getValue(DemuxCompositeELResolver.java:203)
at org.apache.el.parser.AstValue.getValue(AstValue.java:169)
at org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:189)
at com.sun.faces.facelets.el.TagValueExpression.getValue(TagValueExpression.java:109)
… 38 more
02/10/2012 15:56:23 org.apache.catalina.core.StandardWrapperValve invoke
GRAVE: Servlet.service() for servlet [Faces Servlet] in context with path [/PrimeJSFcomHibernate] threw exception [null] with root cause
java.lang.NullPointerException
at dao.UsuarioRN.listar(UsuarioRN.java:13)
at bean.UsuarioBean.getLista(UsuarioBean.java:41)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at javax.el.BeanELResolver.getValue(BeanELResolver.java:87)
at com.sun.faces.el.DemuxCompositeELResolver._getValue(DemuxCompositeELResolver.java:176)
at com.sun.faces.el.DemuxCompositeELResolver.getValue(DemuxCompositeELResolver.java:203)
at org.apache.el.parser.AstValue.getValue(AstValue.java:169)
at org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:189)
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 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 com.sun.faces.renderkit.html_basic.TableRenderer.encodeBegin(TableRenderer.java:81)
at javax.faces.component.UIComponentBase.encodeBegin(UIComponentBase.java:820)
at javax.faces.component.UIData.encodeBegin(UIData.java:1118)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1754)
at javax.faces.render.Renderer.encodeChildren(Renderer.java:168)
at javax.faces.component.UIComponentBase.encodeChildren(UIComponentBase.java:845)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1756)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1759)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1759)
at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:401)
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.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:304)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:240)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:164)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:462)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:164)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:562)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:395)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:250)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:188)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:166)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:302)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)

Vc tem alguma classe DAOHibernate?

tenho esta classe aqui

package banco;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.AnnotationConfiguration;
import org.hibernate.cfg.Configuration;

public class HibernateUtil {
	private static SessionFactory sessionFactory;

	public static SessionFactory getSessionFactory() {
		if (sessionFactory == null) {
			AnnotationConfiguration cfg = new AnnotationConfiguration();
			Configuration config = cfg.configure("hibernate.cfg.xml");
			sessionFactory = config.buildSessionFactory();
		}
		return sessionFactory;
	}

	public static Session getSession() {
		Session sessao = getSessionFactory().openSession();
		return sessao;
	}
}

Essa não, outra por nome de UsuarioDAOHibernate, ele implementa sua interface UsuarioDAO.

public class UsuarioDAOHibernate implements UsuarioDAO

posta ai como está organizado a estrutura de seu projeto.

Pessoal, a estrutura do meu projeto esta no anexo.

desconsidere os pacotes BR e ORG.


package dao;
import java.util.List;

import modelo.Usuario;
public interface UsuarioDAO {
	public List<Usuario> listar();
}


Na sua classe UsuarioRN, usuarioDAO não está instanciado.

Pessoal, minha lista esta nulla…conforme a imagem…abaixo.

como resolver isso ?


Viu o que eu postei?

tentei fazer isso, mas esta dando o seguinte erro : CONNOT INSTANTIATE THE TYPE USUARIODAO


public class UsuarioRN {
	//private UsuarioDAO usuarioDAO;
	UsuarioDAO  usuariodao = new UsuarioDAO();
	public List<Usuario> listar() {
		return usuarioDAO.listar();
	}


}

package dao;
import java.util.List;

import modelo.Usuario;
public interface UsuarioDAO {
	public List<Usuario> listar();
}

Pessoal, resolvi dessa forma

	

	public List<Usuario> listar() {
		Session session = HibernateUtil.getSession();
		Query q = session.createQuery("FROM Usuario");
		return  q.list();  
	
	}