Olá, estou seguindo um tutorial da apostila da K19 e estou afzendo a parte Integração JSF e JPA, pois bem esbarrei no seguinte problema.
Quando executo a pagina carros.xhtml acontece o seguinte:
Stack trace
[code]SEVERE: Error Rendering View[/carros.xhtml]
javax.el.ELException: /carros.xhtml @26,57 rendered="#{not empty carroBean.carros}": java.lang.NullPointerException
at com.sun.faces.facelets.el.TagValueExpression.getValue(TagValueExpression.java:114)
at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:194)
at javax.faces.component.UIComponentBase.isRendered(UIComponentBase.java:462)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1850)
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.StandardWrapper.service(StandardWrapper.java:1682)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:318)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:160)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:734)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:673)
at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:99)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:174)
at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:357)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:260)
at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:188)
at org.glassfish.grizzly.http.server.HttpHandler.runService(HttpHandler.java:191)
at org.glassfish.grizzly.http.server.HttpHandler.doHandle(HttpHandler.java:168)
at org.glassfish.grizzly.http.server.HttpServerFilter.handleRead(HttpServerFilter.java:189)
at org.glassfish.grizzly.filterchain.ExecutorResolver$9.execute(ExecutorResolver.java:119)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeFilter(DefaultFilterChain.java:288)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeChainPart(DefaultFilterChain.java:206)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.execute(DefaultFilterChain.java:136)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.process(DefaultFilterChain.java:114)
at org.glassfish.grizzly.ProcessorExecutor.execute(ProcessorExecutor.java:77)
at org.glassfish.grizzly.nio.transport.TCPNIOTransport.fireIOEvent(TCPNIOTransport.java:838)
at org.glassfish.grizzly.strategies.AbstractIOStrategy.fireIOEvent(AbstractIOStrategy.java:113)
at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.run0(WorkerThreadIOStrategy.java:115)
at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.access$100(WorkerThreadIOStrategy.java:55)
at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy$WorkerThreadRunnable.run(WorkerThreadIOStrategy.java:135)
at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:564)
at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:544)
at java.lang.Thread.run(Thread.java:724)
Caused by: javax.el.ELException: java.lang.NullPointerException
at javax.el.BeanELResolver.getValue(BeanELResolver.java:368)
at com.sun.faces.el.DemuxCompositeELResolver._getValue(DemuxCompositeELResolver.java:176)
at com.sun.faces.el.DemuxCompositeELResolver.getValue(DemuxCompositeELResolver.java:203)
at com.sun.el.parser.AstValue.getValue(AstValue.java:140)
at com.sun.el.parser.AstValue.getValue(AstValue.java:204)
at com.sun.el.parser.AstEmpty.getValue(AstEmpty.java:66)
at com.sun.el.parser.AstNot.getValue(AstNot.java:63)
at com.sun.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:226)
at com.sun.faces.facelets.el.TagValueExpression.getValue(TagValueExpression.java:109)
… 38 more
Caused by: java.lang.NullPointerException
at br.com.k19.modelo.CarroRepository.buscaTodos(CarroRepository.java:20)
at br.com.k19.controle.CarroBean.getCarros(CarroBean.java:36)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at javax.el.BeanELResolver.getValue(BeanELResolver.java:363)
… 46 more
WARNING: StandardWrapperValve[Faces Servlet]: Servlet.service() for servlet Faces Servlet threw exception
java.lang.NullPointerException
at br.com.k19.modelo.CarroRepository.buscaTodos(CarroRepository.java:20)
at br.com.k19.controle.CarroBean.getCarros(CarroBean.java:36)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at javax.el.BeanELResolver.getValue(BeanELResolver.java:363)
at com.sun.faces.el.DemuxCompositeELResolver._getValue(DemuxCompositeELResolver.java:176)
at com.sun.faces.el.DemuxCompositeELResolver.getValue(DemuxCompositeELResolver.java:203)
at com.sun.el.parser.AstValue.getValue(AstValue.java:140)
at com.sun.el.parser.AstValue.getValue(AstValue.java:204)
at com.sun.el.parser.AstEmpty.getValue(AstEmpty.java:66)
at com.sun.el.parser.AstNot.getValue(AstNot.java:63)
at com.sun.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:226)
at com.sun.faces.facelets.el.TagValueExpression.getValue(TagValueExpression.java:109)
at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:194)
at javax.faces.component.UIComponentBase.isRendered(UIComponentBase.java:462)
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1850)
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.StandardWrapper.service(StandardWrapper.java:1682)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:318)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:160)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:734)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:673)
at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:99)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:174)
at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:357)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:260)
at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:188)
at org.glassfish.grizzly.http.server.HttpHandler.runService(HttpHandler.java:191)
at org.glassfish.grizzly.http.server.HttpHandler.doHandle(HttpHandler.java:168)
at org.glassfish.grizzly.http.server.HttpServerFilter.handleRead(HttpServerFilter.java:189)
at org.glassfish.grizzly.filterchain.ExecutorResolver$9.execute(ExecutorResolver.java:119)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeFilter(DefaultFilterChain.java:288)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeChainPart(DefaultFilterChain.java:206)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.execute(DefaultFilterChain.java:136)
at org.glassfish.grizzly.filterchain.DefaultFilterChain.process(DefaultFilterChain.java:114)
at org.glassfish.grizzly.ProcessorExecutor.execute(ProcessorExecutor.java:77)
at org.glassfish.grizzly.nio.transport.TCPNIOTransport.fireIOEvent(TCPNIOTransport.java:838)
at org.glassfish.grizzly.strategies.AbstractIOStrategy.fireIOEvent(AbstractIOStrategy.java:113)
at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.run0(WorkerThreadIOStrategy.java:115)
at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.access$100(WorkerThreadIOStrategy.java:55)
at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy$WorkerThreadRunnable.run(WorkerThreadIOStrategy.java:135)
at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:564)
at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:544)
at java.lang.Thread.run(Thread.java:724)[/code]
Bom pelo que entnedi ele está recebendo Null quando tenta chamar no CarroRepository o metodo buscaTodos(), mas no caso aquela parte do xhtml so deveria ser rederizada se o Bean não estiver vazio,certo?
Bom segue as classes:
/carros.xhtml
<!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>
<title>K19 Treinamentos</title>
</h:head>
<h:body>
<h:form>
<h:panelGrid columns="2">
<h:outputLabel value="Marca: " for="campo-marca" />
<h:inputText value="#{carroBean.carro.marca}" id="campo-marca" />
<h:outputLabel value="Modelo: " for="campo-modelo" />
<h:inputText value="#{carroBean.carro.modelo}" id="campo-modelo" />
<h:commandButton value="Adicionar"
action="#{carroBean.adicionaCarro}" />
</h:panelGrid>
</h:form>
<h:panelGroup rendered="#{not empty carroBean.carros}">
<h1>Lista de carros:</h1>
<ul>
<ui:repeat value="#{carroBean.carros}" var="carro">
<li><h:outputText value="#{carro.marca} #{carro.modelo}" /></li>
</ui:repeat>
</ul>
</h:panelGroup>
</h:body>
</html>CarroBean
package br.com.k19.controle;
import br.com.k19.modelo.Carro;
import br.com.k19.modelo.CarroRepository;
import java.util.List;
import javax.faces.bean.ManagedBean;
import javax.faces.context.ExternalContext;
import javax.faces.context.FacesContext;
import javax.persistence.EntityManager;
import javax.servlet.http.HttpServletRequest;
@ManagedBean
public class CarroBean {
private Carro carro = new Carro();
public Carro getCarro() {
return carro;
}
public void setCarro(Carro carro) {
this.carro = carro;
}
public void adicionaCarro() {
EntityManager manager = this.getEntityManager();
CarroRepository repository = new CarroRepository(manager);
repository.adiciona(this.carro);
this.carro = new Carro();
}
public List<Carro> getCarros() {
EntityManager manager = this.getEntityManager();
CarroRepository repository = new CarroRepository(manager);
return repository.buscaTodos();
}
private EntityManager getEntityManager() {
FacesContext fc = FacesContext.getCurrentInstance();
ExternalContext ec = fc.getExternalContext();
HttpServletRequest request = (HttpServletRequest) ec.getRequest();
EntityManager manager = (EntityManager)request.getAttribute("EntityManager");
return manager;
}
}CarroRepository
[code]package br.com.k19.modelo;
import java.util.List;
import javax.persistence.EntityManager;
import javax.persistence.Query;
public class CarroRepository {
private EntityManager manager;
public CarroRepository(EntityManager manager) {
this.manager = manager;
}
public void adiciona(Carro carro) {
this.manager.persist(carro);
}
public List<Carro> buscaTodos() {
Query query = this.manager.createQuery("select x from Carro");
return query.getResultList();
}
}
[/code]
Carro
package br.com.k19.modelo;
import java.io.Serializable;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
@Entity
public class Carro implements Serializable {
@Id @GeneratedValue
private Long id;
private String marca;
private String modelo;
public String getMarca() {
return marca;
}
public void setMarca(String marca) {
this.marca = marca;
}
public String getModelo() {
return modelo;
}
public void setModelo(String modelo) {
this.modelo = modelo;
}
}EntityManager
[code]package br.com.k19.filters;
import java.io.IOException;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.annotation.WebFilter;
@WebFilter(servletNames={“Faces Servlet”})
public class JPAFilter implements Filter {
private EntityManagerFactory factory;
@Override
public void init(FilterConfig filterConfig) throws ServletException {
this.factory = Persistence.createEntityManagerFactory("K19-PU");
}
@Override
public void destroy() {
this.factory.close();
}
@Override
public void doFilter(ServletRequest request, ServletResponse response,
FilterChain chain) throws IOException, ServletException {
// CHEGADA
EntityManager manager = this.factory.createEntityManager();
request.setAttribute("EntityManager", manager);
manager.getTransaction().begin();
// CHEGADA
// FACES SERVLET
chain.doFilter(request, response);
// FACES SERVLET
// SAÍDA
try {
manager.getTransaction().commit();
} catch (Exception e) {
manager.getTransaction().rollback();
} finally {
manager.close();
}
// SAÍDA
}
}
[/code]
persistence.xml
[quote]<?xml version="1.0" encoding="UTF-8"?>
<persistence-unit name="K19-PU" transaction-type="RESOURCE_LOCAL">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<properties>
<property name="hibernate.dialect" value="org.hibernate.dialect.MySQL5InnoDBDialect"/>
<property name="hibernate.hbm2ddl.auto" value="update" />
<property name="javax.persistence.jdbc.driver" value="com.mysql.jdbc.Driver"/>
<property name="javax.persistence.jdbc.user" value="pedro"/>
<property name="javax.persistence.jdb.password" value="pedro123tim" />
<property name="javax.persistence.jdbc.url" value="jdbc:mysql://localhost:3306/K19-DB"/>
</properties>
</persistence-unit>