Integration jsf, spring, hibernate. How to inject Spring beans into JSF managed beans?

StackOverflow https://stackoverflow.com/questions/23638664

Domanda

I'm working on a Java EE project using frameworks JSF 2.1, Spring 3.1.1.Release, hibernate 3.2.1. now i'm in the phase of integrating the three of them. the build succeeded, i use tomcat server 7. but i get this exception on the the front page.

Etat HTTP 500 -

type Rapport d''exception

message

description Le serveur a rencontré une erreur interne qui l''a empêché de satisfaire la requête.

exception

javax.servlet.ServletException
    javax.faces.webapp.FacesServlet.service(FacesServlet.java:422)
cause mère

java.lang.NullPointerException
    controller.AnneeBean.getListeAnnees(AnneeBean.java:15)
    sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    java.lang.reflect.Method.invoke(Method.java:601)
    javax.el.BeanELResolver.getValue(BeanELResolver.java:87)
    com.sun.faces.el.DemuxCompositeELResolver._getValue(DemuxCompositeELResolver.java:176)
    com.sun.faces.el.DemuxCompositeELResolver.getValue(DemuxCompositeELResolver.java:203)
    org.apache.el.parser.AstValue.getValue(AstValue.java:183)
    org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:185)
    com.sun.faces.facelets.el.TagValueExpression.getValue(TagValueExpression.java:109)
    javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:194)
    javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:182)
    javax.faces.component.UIData.getValue(UIData.java:731)
    javax.faces.component.UIData.getDataModel(UIData.java:1798)
    javax.faces.component.UIData.setRowIndexWithoutRowStatePreserved(UIData.java:484)
    javax.faces.component.UIData.setRowIndex(UIData.java:473)
    com.sun.faces.renderkit.html_basic.TableRenderer.encodeBegin(TableRenderer.java:81)
    javax.faces.component.UIComponentBase.encodeBegin(UIComponentBase.java:820)
    javax.faces.component.UIData.encodeBegin(UIData.java:1118)
    javax.faces.component.UIComponent.encodeAll(UIComponent.java:1754)
    javax.faces.component.UIComponent.encodeAll(UIComponent.java:1759)
    javax.faces.component.UIComponent.encodeAll(UIComponent.java:1759)
    com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:401)
    com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:131)
    com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:121)
    com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
    com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:139)
    javax.faces.webapp.FacesServlet.service(FacesServlet.java:410)
note La trace complète de la cause mère de cette erreur est disponible dans les fichiers journaux de Apache Tomcat/7.0.42.

Hibernate hibernate.cfg.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
  <session-factory>
    <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
    <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
    <property name="hibernate.connection.url">jdbc:mysql://localhost:3306/base?zeroDateTimeBehavior=convertToNull</property>
    <property name="hibernate.connection.username">root</property>
    <mapping resource="net/vo/Annee.hbm.xml"/>
  </session-factory>
</hibernate-configuration>

hibernate.reveng.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-reverse-engineering PUBLIC "-//Hibernate/Hibernate Reverse Engineering DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-reverse-engineering-3.0.dtd">
<hibernate-reverse-engineering>
  <schema-selection match-catalog="base"/>
  <table-filter match-name="annee"/>
</hibernate-reverse-engineering>

AnneeDao.java

package dao;

import java.util.List;
import net.vo.Annee;

public interface AnneeDao {
    public List getAllAnnees();
    public Annee getAnnee(Integer id);
    public void insert(Annee annee);
    public void update(Annee annee);
    public void delete(Integer id);
}

AnneeHibernateDao.java

package dao;

import java.util.List;
import net.vo.Annee;
import org.hibernate.HibernateException;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;

public class AnneeHibernateDao implements AnneeDao{
    private List<Annee> listeAnnees;
    private Annee annee;
    public void init()
    {
        System.out.println("Méthode d'initiation");
    }
    @Override
    public List getAllAnnees() {
        Session session=HibernateUtil.getSession();
        try
        {
            session.beginTransaction();
            listeAnnees = session.createQuery("from Annee").list();
            return listeAnnees;
        }
        catch(HibernateException e)
        {
            throw e;
        }
        finally
        {
            session.close();
        }
    }

    @Override
    public Annee getAnnee(Integer id) {
       Session session = HibernateUtil.getSession();
       try
       {
           session.beginTransaction();
           Query q = session.createQuery("from Annee as a where a.annee=" + id);
           return (Annee) q.uniqueResult();
       }
       finally
       {
           session.close();
       }
    }

    @Override
    public void insert(Annee annee) {

      Session session = HibernateUtil.getSession();
      Transaction tx=null;
      try
      {
          tx = session.beginTransaction();
          session.save(annee);
          tx.commit();         
      }
      catch(RuntimeException e)
      {
          if(tx != null) 
            {
                tx.rollback();
            }
          throw e;
      }
      finally
      {
          session.close();
      }
    }

    @Override
    public void update(Annee annee) {
        Session session = HibernateUtil.getSession();
        Transaction tx=null;
        try
        {
            tx=session.beginTransaction();
            session.update(annee);
            tx.commit();
        }
         catch(RuntimeException e)
         {
           if(tx != null) 
            {
                tx.rollback();
            }
            throw e;
         }
         finally
         {
            session.close();
         }
    }

    @Override
    public void delete(Integer id) {
       Session session = HibernateUtil.getSession();
       Transaction tx = null;
       try
       {
           tx=session.beginTransaction();
           annee = (Annee) session.get(Annee.class,id);
           session.delete(annee);
           tx.commit();
       }
       catch(RuntimeException e)
         {
            if(tx != null) 
            {
                tx.rollback();
            }
            throw e;
         }
         finally
         {
            session.close();
         }
    }


}

HibernateUtil.java

package dao;

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

/**
 * Hibernate Utility class with a convenient method to get Session Factory
 * object.
 *
 * @author images
 */
public class HibernateUtil {

    private static final SessionFactory sessionFactory;

    static {
        try {
            // Create the SessionFactory from standard (hibernate.cfg.xml) 
            // config file.
            sessionFactory = new AnnotationConfiguration().configure().buildSessionFactory();
        } catch (Throwable ex) {
            // Log the exception. 
            System.err.println("Initial SessionFactory creation failed." + ex);
            throw new ExceptionInInitializerError(ex);
        }
    }

    public static Session getSession() {
        return sessionFactory.openSession();
    }
}

Pojo file

Annee.java

package net.vo;

public class Annee  implements java.io.Serializable {


     private int annee;

    public Annee() {
    }

    public Annee(int annee) {
       this.annee = annee;
    }

    public int getAnnee() {
        return this.annee;
    }

    public void setAnnee(int annee) {
        this.annee = annee;
    }




}

Mapping file : Annee.hbm.xml

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<!-- Generated 13 mai 2014 18:23:22 by Hibernate Tools 3.2.1.GA -->
<hibernate-mapping>
    <class name="net.vo.Annee" table="annee" catalog="base">
        <id name="annee" type="int">
            <column name="annee" />
            <generator class="assigned" />
        </id>
    </class>
</hibernate-mapping>

Spring AnneeMetier.java

package model.services;

import java.util.List;

public interface AnneeMetier {
    public List getAllAnnees();
}

AnneeMetierImpl.java

package model.services;

import dao.AnneeDao;
import java.util.List;
import net.vo.Annee;

public class AnneeMetierImpl implements AnneeMetier{

    private AnneeDao anneeDao;

    @Override
    public List getAllAnnees() {
            return anneeDao.getAllAnnees();
    }

    public void setAnneeDao(AnneeDao anneeDao) {
        this.anneeDao = anneeDao;
    }

    public AnneeDao getAnneeDao() {
        return anneeDao;
    }

}

JSF AnneeBean.java

package controller;

import java.util.List;
import model.services.AnneeMetier;
import net.vo.Annee;

public class AnneeBean {

    private AnneeMetier anneeMetier;

    private List<Annee> listeAnnees;

    public List getListeAnnees() {
        listeAnnees = anneeMetier.getAllAnnees();
        return listeAnnees;
    }

    public void setListeAnnees(List listeAnnees) {
        this.listeAnnees = listeAnnees;
    }

    public AnneeMetier getAnneeMetier() {
        return anneeMetier;
    }

    public void setAnneeMetier(AnneeMetier anneeMetier) {
        this.anneeMetier = anneeMetier;
    }

}

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="3.0" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd">
       <listener>
      <listener-class>
         org.springframework.web.context.ContextLoaderListener
      </listener-class>
   </listener>
   <listener>
      <listener-class>
         org.springframework.web.context.request.RequestContextListener
      </listener-class>
   </listener>
    <context-param>
        <param-name>javax.faces.PROJECT_STAGE</param-name>
        <param-value>WEB-INF/applicationContext.xml</param-value>
    </context-param>
    <servlet>
        <servlet-name>Faces Servlet</servlet-name>
        <servlet-class>javax.faces.webapp.FacesServlet</servlet-class>
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>Faces Servlet</servlet-name>
        <url-pattern>/faces/*</url-pattern>
    </servlet-mapping>
    <session-config>
        <session-timeout>
            30
        </session-timeout>
    </session-config>
    <welcome-file-list>
        <welcome-file>faces/index.xhtml</welcome-file>
    </welcome-file-list>
</web-app>

applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:aop="http://www.springframework.org/schema/aop/spring-aop-3.1.xsd"
       xmlns:context="http://www.springframework.org/schema/context/spring-context-3.1.xsd"
       xmlns:tx="http://www.springframework.org/schema/tx/spring-tx-3.1.xsd"

       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd
          http://www.springframework.org/schema/aop/spring-aop-3.1.xsd http://www.springframework.org/schema/aop/spring-aop-3.1.xsd/spring-spring-aop-3.1.xsd-3.1.1.RELEASE.xsd
          http://www.springframework.org/schema/context/spring-context-3.1.xsd http://www.springframework.org/schema/context/spring-context-3.1.xsd/spring-spring-context-2.5.xsd-3.1.1.RELEASE.xsd
          http://www.springframework.org/schema/tx/spring-tx-3.1.xsd http://www.springframework.org/schema/tx/spring-tx-3.1.xsd/spring-spring-tx-3.1.xsd-3.1.1.RELEASE.xsd
">
     <bean id="anneeDao" class="dao.AnneeHibernateDao"></bean>
    <bean id="anneeMetier" class="model.services.AnneeMetierImpl">
        <property name="anneeDao" ref="anneeDao"/>  
    </bean>  

</beans>

faces-config.xml

<?xml version='1.0' encoding='UTF-8'?>

<!-- =========== FULL CONFIGURATION FILE ================================== -->

<faces-config version="2.1"
    xmlns="http://java.sun.com/xml/ns/javaee"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-facesconfig_2_1.xsd">

<application>
   <variable-resolver>
      org.springframework.web.jsf.DelegatingVariableResolver
   </variable-resolver>
</application>
 <managed-bean>
      <managed-bean-name>anneeBean</managed-bean-name>
      <managed-bean-class>controller.AnneeBean</managed-bean-class>
      <managed-bean-scope>request</managed-bean-scope>
   </managed-bean> 
</faces-config>

index.xhtml

<?xml version='1.0' encoding='UTF-8' ?>
<!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:p="http://primefaces.org/ui">
    <h:head>
        <title>Facelet Title</title>
    </h:head>
    <h:body>
        <h:dataTable var="annees" value="#{anneeBean.listeAnnees}">
                    <p:column headerText="Annee">
                        <h:outputText value="#{annee.annees}"/>
                    </p:column>
                </h:dataTable>
    </h:body>
</html>

please could you help me, i will appreciate it a lot

edit : this is the stacktrace updated

mai 14, 2014 1:14:41 AM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet [Faces Servlet] in context with path [/testJSF_Spring_Hibernate] threw exception [Erreur lors de linjection de ressources dans le bean géré anneeBean] with root cause
java.lang.NullPointerException
    at model.services.AnneeMetierImpl.getAllAnnees(AnneeMetierImpl.java:17)
    at controller.AnneeBean.init(AnneeBean.java:25)
    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:601)
    at com.sun.faces.vendor.WebContainerInjectionProvider.invokeAnnotatedMethod(WebContainerInjectionProvider.java:117)
    at com.sun.faces.vendor.WebContainerInjectionProvider.invokePostConstruct(WebContainerInjectionProvider.java:99)
    at com.sun.faces.mgbean.BeanBuilder.invokePostConstruct(BeanBuilder.java:223)
    at com.sun.faces.mgbean.BeanBuilder.build(BeanBuilder.java:105)
    at com.sun.faces.mgbean.BeanManager.createAndPush(BeanManager.java:409)
    at com.sun.faces.mgbean.BeanManager.create(BeanManager.java:269)
    at com.sun.faces.el.ManagedBeanELResolver.resolveBean(ManagedBeanELResolver.java:244)
    at com.sun.faces.el.ManagedBeanELResolver.getValue(ManagedBeanELResolver.java:116)
    at com.sun.faces.el.DemuxCompositeELResolver._getValue(DemuxCompositeELResolver.java:176)
    at com.sun.faces.el.DemuxCompositeELResolver.getValue(DemuxCompositeELResolver.java:203)
    at com.sun.faces.el.ChainAwareVariableResolver.resolveVariable(ChainAwareVariableResolver.java:107)
    at org.springframework.web.jsf.DelegatingVariableResolver.resolveOriginal(DelegatingVariableResolver.java:123)
    at org.springframework.web.jsf.DelegatingVariableResolver.resolveVariable(DelegatingVariableResolver.java:108)
    at com.sun.faces.el.VariableResolverChainWrapper.getValue(VariableResolverChainWrapper.java:115)
    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.AstIdentifier.getValue(AstIdentifier.java:72)
    at org.apache.el.parser.AstValue.getValue(AstValue.java:161)
    at org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:185)
    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.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:305)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1023)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589)
    at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:1852)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
    at java.lang.Thread.run(Thread.java:722)

edit 2 : this is the AnneeBean Class

package controller;

import java.util.List;
import javax.annotation.PostConstruct;
import model.services.AnneeMetier;
import model.services.AnneeMetierImpl;
import net.vo.Annee;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Scope;
import org.springframework.stereotype.Component;

@Component
@Scope("view")
public class AnneeBean {

    @Autowired
    private AnneeMetier anneeMetier;

    private List<Annee> listeAnnees;

    @PostConstruct
    public void init() {
        anneeMetier = new AnneeMetierImpl();
        listeAnnees = anneeMetier.getAllAnnees();
    }
    public List getListeAnnees() {
        listeAnnees = anneeMetier.getAllAnnees();
        return listeAnnees;
    }

    public void setListeAnnees(List listeAnnees) {
        this.listeAnnees = listeAnnees;
    }

    public AnneeMetier getAnneeMetier() {
        return anneeMetier;
    }

    public void setAnneeMetier(AnneeMetier anneeMetier) {
        this.anneeMetier = anneeMetier;
    }

}

edit 3 : index.xhtml

<?xml version='1.0' encoding='UTF-8' ?>
<!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:p="http://primefaces.org/ui"
      xmlns:f="http://java.sun.com/jsf/core">
    <h:head>
        <title>Facelet Title</title>
    </h:head>
    <h:body>
 <h:form>
     <p:dataTable var="listeAnnees" value="#{anneeBean.listeAnnees}">
                <p:column headerText="Annee">
                    <h:outputText value="#{listeAnnees.annee}"/>
                    </p:column>
            </p:dataTable>        
        </h:form>
    </h:body>
</html>
È stato utile?

Soluzione

The naive solution for non-JSF developers would be to simply initialize the variables inside the getter to resolve the null value in the attributes. This is:

public List getListeAnnees() {
    listeAnnees = getAnneeMetier().getAllAnnees();
    return listeAnnees;
}

public AnneeMetier getAnneeMetier() {
    if (anneeMetier == null) {
        anneeMetier = new AnneeMetierImpl();
    }
    return anneeMetier;
}

But this may generate lot of overhead from server in case AnneeMetier#getAllAnnees() retrieves the data from database. This is explained here: Why JSF calls getters multiple times

To solve this, you do two things:

  1. Define the right scope of your bean.
  2. Initialize the necessary data for work using @PostConstruct annotated method.

And this would result in:

  1. Defining the scope as @ViewScoped (explained in the link above).
  2. Initializing listeAnnees in @PostConstruct method.
  3. Remove any business logic from getters/setters

So the code would look like this:

@ManagedBean
@ViewScoped
public class AnneeBean {
    private AnneeMetier anneeMetier;
    private List<Annee> listeAnnees;

    @PostConstruct
    public void init() {
        anneeMetier = new AnneeMetierImpl();
        listeAnnees = anneeMetier.getAllAnnees();
    }

    public List getListeAnnees() {
        return listeAnnees;
    }

    public void setListeAnnees(List listeAnnees) {
        this.listeAnnees = listeAnnees;
    }

    public AnneeMetier getAnneeMetier() {
        return anneeMetier;
    }

    public void setAnneeMetier(AnneeMetier anneeMetier) {
        this.anneeMetier = anneeMetier;
    }
}

BUT since you're trying to integrate JSF with Spring, you have to take into account that Spring has not yet full support of JSF 2 @ViewScoped annotation. For this case, you have/need to implement it yourself. There are plenty examples on the net about this, and looks that the most popular is from Cagatay's. In this way, you'll be able to gain power from both sides. And your bean will look like this:

@Component
@Scope("view")
public class AnneeBean {
    @Autowired
    private AnneeMetier anneeMetier;
    private List<Annee> listeAnnees;

    @PostConstruct
    public void init() {
        listeAnnees = anneeMetier.getAllAnnees();
    }

    public List getListeAnnees() {
        return listeAnnees;
    }

    public void setListeAnnees(List listeAnnees) {
        this.listeAnnees = listeAnnees;
    }
}

More info:

Since you're learning Spring, the best bet would be to enable component scan and use annotations to configure your spring beans. Do the following:

  • Remove any bean configuration in applicationContext.xml.

  • Add this configuration to enable bean scan annotations:

    <!-- 
    These will enable component scan by annotation configuration
    rather than XML configuration. One per package
-->
<context:component-scan base-package="dao" />
<context:component-scan base-package="model.services" />

    Or if all your classes are inside one root package.

    <!--
    Assuming there's a root package for your packages like this
<context:component-scan base-package="com.myproject.dao" />
<context:component-scan base-package="com.myproject.model.services" />
-->
<context:component-scan base-package="com.myproject" />

  • Start configuring your Spring managed beans by annotations:

    @Repository
public class AnneeHibernateDao implements AnneeDao{
    //...
}

@Service
public class AnneeMetierImpl implements AnneeMetier{
    @Autowired
    private AnneeDao anneeDao;
    //...
}

Compile your project and run it.

Altri suggerimenti

You are using getListeAnnees where you intend to call a method of your private object called anneeMetier, which is not initialized yet. You initialize that object through your setAnneeMetier method, which is never initialized in your code, therefore it is null. You can solve your problem by doing one of the following:

  1. You initialize anneeMetier by calling the setAnneeMetier before you use getListeAnnees

  2. You implement a constructor for your AnneeBean class where you initialize anneeMetier

  3. You modify your getter (getListeAnnees) to be such as follows:

    public List getListeAnnees() { if (anneeMetier == null) { return new ArrayList<Annee>(); } listeAnnees = anneeMetier.getAllAnnees(); return listeAnnees; }

EDIT: pL4GU33's comment might be useful, so I add his comment's idea to the answer:

public List getListeAnnees() { if (anneeMetier == null) { return Collections.emptyList(); } listeAnnees = anneeMetier.getAllAnnees(); return listeAnnees; }

His solution is more type-agnostic, so I upvote his comment.

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