Exception occurred during processing request: null: java.lang.NullPointerException in DAO bean

Question

I have a problem in create() and insert() methods that are used with my database. I'm using Struts, Hibernate, and MySQL as a database.

I've been trying to solve this problem for a long time but without any result.

My class model:

package clowzer.charaf.model;

import java.util.Date;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Table;
import javax.persistence.Temporal;
import javax.persistence.TemporalType;


@Entity 
@Table (name="JOUEUR")
public class Joueur{

@Id 
@Column(name="id")
private Integer id;

@Column(name="nom" )
private String nom;

@Column(name="prenom")
private String prenom;

@Column(name="pseudo")
private String pseudo;

@Column(name="login")
private String login;

@Column(name="image")
private String image;

@Column(name = "datecreationcompte")
@Temporal(TemporalType.TIMESTAMP)
private Date datecreationcompte;

@Column(name="motdepasse")
private String motdepasse;

@Column(name="statut")
private Integer statut;

@Column(name="xx")
private String xx;














public Integer getId() {
    return id;
}

public void setId(Integer id) {
    this.id = id;
}

public String getNom() {
    return nom;
}

public void setNom(String nom) {
    this.nom = nom;
}

public String getPrenom() {
    return prenom;
}

public void setPrenom(String prenom) {
    this.prenom = prenom;
}

public String getPseudo() {
    return pseudo;
}

public void setPseudo(String pseudo) {
    this.pseudo = pseudo;
}

public String getLogin() {
    return login;
}

public void setLogin(String login) {
    this.login = login;
}

public String getImage() {
    return image;
}

public void setImage(String image) {
    this.image = image;
}

public Date getDatecreationcompte() {
    return datecreationcompte;
}

public void setDatecreationcompte(Date datecreationcompte) {
    this.datecreationcompte = datecreationcompte;
}

public String getMotdepasse() {
    return motdepasse;
}

public void setMotdepasse(String motdepasse) {
    this.motdepasse = motdepasse;
}

public Integer getStatut() {
    return statut;
}

public void setStatut(Integer statut) {
    this.statut = statut;
}

public String getXx() {
    return xx;
}

public void setXx(String xx) {
    this.xx = xx;
}

}

My DAO class:

package clowzer.charaf.dao.joueur;


import java.util.List;
import org.hibernate.SessionFactory;
import org.springframework.beans.factory.annotation.Autowired;
import clowzer.charaf.model.Joueur;

public class JoueurDaoImpl implements JoueurDAO {

@Autowired 
SessionFactory sessionFactory;

public void setSessionFactory(SessionFactory sessionFactory) {
    this.sessionFactory = sessionFactory;
}


@Override
public void ajouterjoueur(Joueur joueur) {
    sessionFactory.getCurrentSession().saveOrUpdate(joueur);        
}

My beans:

<?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"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:jee="http://www.springframework.org/schema/jee" xmlns:lang="http://www.springframework.org/schema/lang"
xmlns:p="http://www.springframework.org/schema/p" xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:util="http://www.springframework.org/schema/util"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
    http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd
    http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd
    http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee.xsd
    http://www.springframework.org/schema/lang http://www.springframework.org/schema/lang/spring-lang.xsd
    http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd
    http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util.xsd">


<context:annotation-config />


<!-- CONNEXION JDBC -->
<bean id="propertyConfigurer"
    class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"
    p:location="/WEB-INF/jdbc.properties" />

<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource"
    destroy-method="close" p:driverClassName="com.mysql.jdbc.Driver"
    p:url="jdbc:mysql://localhost/mybase" p:username="root" p:password="root" />

<!-- FIN CONNEXION JDBC -->

<bean id="sessionFactory"
    class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
    <property name="dataSource" ref="dataSource" />
    <property name="configLocation">
        <value>classpath:hibernate.cfg.xml</value>
    </property>
    <property name="hibernateProperties">
        <props>
             <prop key="hibernate.dialect">org.hibernate.dialect.MySQLDialect</prop>  
            <prop key="hibernate.show_sql">false</prop>
        </props>
    </property>
</bean>


<bean id="joueurDao" class="clowzer.charaf.dao.joueur.JoueurDaoImpl"></bean>
<bean id="joueurManager"    class="clowzer.charaf.service.joueur.JoueurManagerImpl"></bean>


<bean id="transactionManager"
    class="org.springframework.orm.hibernate4.HibernateTransactionManager">
    <property name="sessionFactory" ref="sessionFactory" />
</bean>


                                            
<tx:annotation-driven  transaction-manager="transactionManager" />

Error msg :

2016-12-02 09:57:30,204 ERROR [org.apache.struts2.dispatcher.Dispatcher] - <Exception occurred during processing request: null>
java.lang.NullPointerException
at    clowzer.charaf.dao.joueur.JoueurDaoImpl.ajouterjoueur(JoueurDaoImpl.java:57)
at clowzer.charaf.controleur.joueur.Joueur.ajouterjoueur(Joueur.java:106)
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 com.opensymphony.xwork2.DefaultActionInvocation.invokeAction(DefaultActionInvocation.java:446)
at com.opensymphony.xwork2.DefaultActionInvocation.invokeActionOnly(DefaultActionInvocation.java:285)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)
at org.apache.struts2.interceptor.debugging.DebuggingInterceptor.intercept(DebuggingInterceptor.java:256)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:242)
at com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:176)
at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:242)
at com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:265)
at org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept(AnnotationValidationInterceptor.java:68)
at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:242)
at com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:138)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:242)
at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:238)
at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:242)
at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:238)
at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:242)
at com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:191)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:242)
at org.apache.struts2.interceptor.MultiselectInterceptor.intercept(MultiselectInterceptor.java:75)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:242)
at org.apache.struts2.interceptor.CheckboxInterceptor.intercept(CheckboxInterceptor.java:90)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:242)
at org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:252)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:242)
at com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor.intercept(ModelDrivenInterceptor.java:100)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:242)
at com.opensymphony.xwork2.interceptor.ScopedModelDrivenInterceptor.intercept(ScopedModelDrivenInterceptor.java:141)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:242)
at com.opensymphony.xwork2.interceptor.ChainingInterceptor.intercept(ChainingInterceptor.java:145)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:242)
at com.opensymphony.xwork2.interceptor.PrepareInterceptor.doIntercept(PrepareInterceptor.java:171)
at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:242)
at com.opensymphony.xwork2.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:176)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:242)
at org.apache.struts2.interceptor.ServletConfigInterceptor.intercept(ServletConfigInterceptor.java:164)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:242)
at com.opensymphony.xwork2.interceptor.AliasInterceptor.intercept(AliasInterceptor.java:193)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:242)
at com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:187)
at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:242)
at org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:54)
at org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:544)
at org.apache.struts2.dispatcher.ng.ExecuteOperations.executeAction(ExecuteOperations.java:77)
at org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.doFilter(StrutsPrepareAndExecuteFilter.java:91)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1070)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:316)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Unknown Source)

Answer 1

How do you create your DAO beans? The configuration doesn't have required property reference. It can't just autowire without knowing beans configuration.

<property name="sessionFactory" ref="sessionFactory" />

Struts-Spring intergration is available via plugin. From the logs you didn't use a Spring and Struts 2 integration. Struts and spring are integrated via Spring plugin. Struts by default autowires by name. So you can inject your DAO or services directly to the action bean. You don't need to write configuration for action controllers, but for other beans you have to.

How this works

The Spring Plugin works by overriding the Struts ObjectFactory to enhance the creation of core framework objects. When an object is to be created, it uses the class attribute in the Struts configuration to correspond to the id attribute in the Spring configuration. If not found, the class will try to be created as usual, then be autowired by Spring. In the case of Actions, Spring 2's bean scope feature can be used to scope an Action instance to the session, application, or a custom scope, providing advanced customization above the default per-request scoping.

To use a plugin just add it to the classpath.

To enable Spring integration, simply include struts2-spring-plugin-x-x-x.jar in your application.

Answer 2

As far as the stack trace is concerned, it appears that your

sessionFactory.getCurrentSession().saveOrUpdate(joueur);  

is having issue, either your getCurrentSession() is null or your entity is null.

You may need to check for any exception that have occurred in the startup logs of the web application, this issue is most probably related to Hibernate Initialization and database connection.