Erro JSF + Jasper IReport [RESOLVIDO]

Pessoal estou tentando exportar um relatório em pdf e aparecer o seguinte erro que não estou conseguindo corrigir, por gentileza preciso de ajuda Valeu !!!

Ago 03, 2014 10:46:01 PM javax.faces.event.MethodExpressionActionListener processAction
Grave: 'net.sf.jasperreports.engine.JRException' recebido ao invocar escuta de ação '#{consultaUsuarioBean.exportarPDF}' para o componente 'ExportarPBF'
Ago 03, 2014 10:46:01 PM javax.faces.event.MethodExpressionActionListener processAction
Grave: net.sf.jasperreports.engine.JRException: Error retrieving field value from bean : usuario_codigo_usuario
	at net.sf.jasperreports.engine.data.JRAbstractBeanDataSource.getBeanProperty(JRAbstractBeanDataSource.java:123)
	at net.sf.jasperreports.engine.data.JRAbstractBeanDataSource.getFieldValue(JRAbstractBeanDataSource.java:96)
	at net.sf.jasperreports.engine.data.JRBeanCollectionDataSource.getFieldValue(JRBeanCollectionDataSource.java:100)
	at net.sf.jasperreports.engine.fill.JRFillDataset.setOldValues(JRFillDataset.java:823)
	at net.sf.jasperreports.engine.fill.JRFillDataset.next(JRFillDataset.java:787)
	at net.sf.jasperreports.engine.fill.JRBaseFiller.next(JRBaseFiller.java:1478)
	at net.sf.jasperreports.engine.fill.JRVerticalFiller.fillReport(JRVerticalFiller.java:125)
	at net.sf.jasperreports.engine.fill.JRBaseFiller.fill(JRBaseFiller.java:942)
	at net.sf.jasperreports.engine.fill.JRBaseFiller.fill(JRBaseFiller.java:860)
	at net.sf.jasperreports.engine.fill.JRFiller.fillReport(JRFiller.java:84)
	at net.sf.jasperreports.engine.JasperFillManager.fillReport(JasperFillManager.java:624)
	at net.sf.jasperreports.engine.JasperFillManager.fillReport(JasperFillManager.java:540)
	at br.com.laboratorioweb.view.ConsultaUsuarioBean.exportarPDF(ConsultaUsuarioBean.java:67)
	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 org.apache.el.parser.AstValue.invoke(AstValue.java:262)
	at org.apache.el.MethodExpressionImpl.invoke(MethodExpressionImpl.java:278)
	at com.sun.faces.facelets.el.TagMethodExpression.invoke(TagMethodExpression.java:105)
	at javax.faces.event.MethodExpressionActionListener.processAction(MethodExpressionActionListener.java:148)
	at javax.faces.event.ActionEvent.processListener(ActionEvent.java:88)
	at javax.faces.component.UIComponentBase.broadcast(UIComponentBase.java:769)
	at javax.faces.component.UICommand.broadcast(UICommand.java:300)
	at javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:795)
	at javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:1260)
	at com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:81)
	at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
	at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118)
	at javax.faces.webapp.FacesServlet.service(FacesServlet.java:593)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:304)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
	at br.com.laboratorioweb.util.HibernateSessionFilter.doFilter(HibernateSessionFilter.java:30)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
	at org.apache.catalina.filters.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:108)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:224)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:169)
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:581)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
	at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:929)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:405)
	at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:964)
	at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:515)
	at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:302)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
	at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.NoSuchMethodException: Unknown property 'usuario_codigo_usuario' on class 'class br.com.laboratorioweb.model.Usuario'
	at org.apache.commons.beanutils.PropertyUtilsBean.getSimpleProperty(PropertyUtilsBean.java:1313)
	at org.apache.commons.beanutils.PropertyUtilsBean.getNestedProperty(PropertyUtilsBean.java:762)
	at org.apache.commons.beanutils.PropertyUtilsBean.getProperty(PropertyUtilsBean.java:837)
	at org.apache.commons.beanutils.PropertyUtils.getProperty(PropertyUtils.java:426)
	at net.sf.jasperreports.engine.data.JRAbstractBeanDataSource.getBeanProperty(JRAbstractBeanDataSource.java:111)
	... 51 more

Ago 03, 2014 10:46:01 PM com.sun.faces.context.ExceptionHandlerImpl log
Grave: JSF1073: javax.faces.event.AbortProcessingException obtido durante o processamento de INVOKE_APPLICATION 5: UIComponent-ClientId=impressao:ExportarPBF, Message=/ConsultaUsuario.xhtml @63,113 actionListener="#{consultaUsuarioBean.exportarPDF}": net.sf.jasperreports.engine.JRException: Error retrieving field value from bean : usuario_codigo_usuario
Ago 03, 2014 10:46:01 PM com.sun.faces.context.ExceptionHandlerImpl log
Grave: /ConsultaUsuario.xhtml @63,113 actionListener="#{consultaUsuarioBean.exportarPDF}": net.sf.jasperreports.engine.JRException: Error retrieving field value from bean : usuario_codigo_usuario
javax.faces.event.AbortProcessingException: /ConsultaUsuario.xhtml @63,113 actionListener="#{consultaUsuarioBean.exportarPDF}": net.sf.jasperreports.engine.JRException: Error retrieving field value from bean : usuario_codigo_usuario
	at javax.faces.event.MethodExpressionActionListener.processAction(MethodExpressionActionListener.java:182)
	at javax.faces.event.ActionEvent.processListener(ActionEvent.java:88)
	at javax.faces.component.UIComponentBase.broadcast(UIComponentBase.java:769)
	at javax.faces.component.UICommand.broadcast(UICommand.java:300)
	at javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:795)
	at javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:1260)
	at com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:81)
	at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
	at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118)
	at javax.faces.webapp.FacesServlet.service(FacesServlet.java:593)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:304)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
	at br.com.laboratorioweb.util.HibernateSessionFilter.doFilter(HibernateSessionFilter.java:30)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
	at org.apache.catalina.filters.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:108)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:224)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:169)
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:581)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
	at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:929)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:405)
	at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:964)
	at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:515)
	at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:302)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
	at java.lang.Thread.run(Unknown Source)
Caused by: net.sf.jasperreports.engine.JRException: Error retrieving field value from bean : usuario_codigo_usuario
	at net.sf.jasperreports.engine.data.JRAbstractBeanDataSource.getBeanProperty(JRAbstractBeanDataSource.java:123)
	at net.sf.jasperreports.engine.data.JRAbstractBeanDataSource.getFieldValue(JRAbstractBeanDataSource.java:96)
	at net.sf.jasperreports.engine.data.JRBeanCollectionDataSource.getFieldValue(JRBeanCollectionDataSource.java:100)
	at net.sf.jasperreports.engine.fill.JRFillDataset.setOldValues(JRFillDataset.java:823)
	at net.sf.jasperreports.engine.fill.JRFillDataset.next(JRFillDataset.java:787)
	at net.sf.jasperreports.engine.fill.JRBaseFiller.next(JRBaseFiller.java:1478)
	at net.sf.jasperreports.engine.fill.JRVerticalFiller.fillReport(JRVerticalFiller.java:125)
	at net.sf.jasperreports.engine.fill.JRBaseFiller.fill(JRBaseFiller.java:942)
	at net.sf.jasperreports.engine.fill.JRBaseFiller.fill(JRBaseFiller.java:860)
	at net.sf.jasperreports.engine.fill.JRFiller.fillReport(JRFiller.java:84)
	at net.sf.jasperreports.engine.JasperFillManager.fillReport(JasperFillManager.java:624)
	at net.sf.jasperreports.engine.JasperFillManager.fillReport(JasperFillManager.java:540)
	at br.com.laboratorioweb.view.ConsultaUsuarioBean.exportarPDF(ConsultaUsuarioBean.java:67)
	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 org.apache.el.parser.AstValue.invoke(AstValue.java:262)
	at org.apache.el.MethodExpressionImpl.invoke(MethodExpressionImpl.java:278)
	at com.sun.faces.facelets.el.TagMethodExpression.invoke(TagMethodExpression.java:105)
	at javax.faces.event.MethodExpressionActionListener.processAction(MethodExpressionActionListener.java:148)
	... 31 more
Caused by: java.lang.NoSuchMethodException: Unknown property 'usuario_codigo_usuario' on class 'class br.com.laboratorioweb.model.Usuario'
	at org.apache.commons.beanutils.PropertyUtilsBean.getSimpleProperty(PropertyUtilsBean.java:1313)
	at org.apache.commons.beanutils.PropertyUtilsBean.getNestedProperty(PropertyUtilsBean.java:762)
	at org.apache.commons.beanutils.PropertyUtilsBean.getProperty(PropertyUtilsBean.java:837)
	at org.apache.commons.beanutils.PropertyUtils.getProperty(PropertyUtils.java:426)
	at net.sf.jasperreports.engine.data.JRAbstractBeanDataSource.getBeanProperty(JRAbstractBeanDataSource.java:111)
	... 51 more

Resolvido com este código:

public void exportarPDF(ActionEvent actionEvent) throws JRException, IOException{
		Map<String,Object> parametros= new HashMap<String,Object>();
		parametros.put("usuario", "usuario");
		
		File jasper = new File(FacesContext.getCurrentInstance().getExternalContext().getRealPath("/relatorios/listaUsuarios.jasper"));
		JasperPrint jasperPrint = JasperFillManager.fillReport(jasper.getPath(),parametros, new JRBeanCollectionDataSource(this.getUsuarios()));
		
		HttpServletResponse response = (HttpServletResponse) FacesContext.getCurrentInstance().getExternalContext().getResponse();
		response.addHeader("Content-disposition","attachment; filename=listaUsuarios.pdf");
		ServletOutputStream stream = response.getOutputStream();
		
		JasperExportManager.exportReportToPdfStream(jasperPrint, stream);
		
		stream.flush();
		stream.close();
		FacesContext.getCurrentInstance().responseComplete();
	}