title: Failed to instantiate bean Constructor threw exception; nested exception is java.lang.NullPointerException
body: <p>My java based config is </p>
  
  <pre><code>@Configuration
  @ComponentScan(basePackages = { "com.doly.jproject" })
  @EnableTransactionManagement 
  @EnableJpaRepositories (basePackages = "com.doly.jproject.repository")
  public class RootConfigurer extends WebMvcConfigurerAdapter {   
  
      private Properties jpaProperties;   
  
      @Bean
      public DriverManagerDataSource dataSource() {
          DriverManagerDataSource dataSource = new DriverManagerDataSource();
          dataSource.setDriverClassName("com.mysql.jdbc.Driver");
          dataSource.setUrl("jdbc:mysql://localhost/dbga");
          dataSource.setUsername("root");
          dataSource.setPassword("");
          return dataSource;
      } 
  
      @Bean
      public EntityManagerFactory entityManagerFactory() throws SQLException {
  
          LocalContainerEntityManagerFactoryBean entityManagerFactory = 
                  new LocalContainerEntityManagerFactoryBean();
          entityManagerFactory.setPackagesToScan("com.doly.jproject.entity");
          entityManagerFactory.setDataSource(dataSource());
  
          jpaProperties = new Properties();       
          jpaProperties.put("hibernate.show_sql", true);
          jpaProperties.put("hibernate.hbm2ddl.auto", "create");
  
          entityManagerFactory.setJpaProperties(jpaProperties);
          entityManagerFactory.setPersistenceProvider(new HibernatePersistenceProvider());
  
          return entityManagerFactory.getObject();
      }
  
  
      @Bean
      @Qualifier(value = "entityManager")
      public EntityManager entityManager(EntityManagerFactory entityManagerFactory) {
          return entityManagerFactory.createEntityManager();
      }
  
      @Bean
      public JpaTransactionManager transactionManager() {
          JpaTransactionManager transactionManager = new JpaTransactionManager();
          transactionManager.setDataSource(dataSource());
          return transactionManager;
      }
  }
  </code></pre>
  
  <p>but when I want to initialize object of <code>org.hibernate.Session</code> from <code>javax.persistence.EntityManager</code> in my @Service class as </p>
  
  <pre><code>@Autowired
  @Qualifier(value = "entityManager")
  private EntityManager entityManager;    
  private Session session = entityManager.unwrap(org.hibernate.Session.class);
  </code></pre>
  
  <p>I get error + stacktrace as</p>
  
  <pre><code>    SEVERE: Exception sending context initialized event to listener instance of class org.springframework.web.context.ContextLoaderListener
  org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'homeController': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private com.doly.jproject.service.VidService com.doly.jproject.controllers.HomeController.vidService; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'vidService' defined in file [F:\Spring Workspace\.metadata\.plugins\org.eclipse.wst.server.core\tmp0\wtpwebapps\jobsnetwork\WEB-INF\classes\com\doly\jproject\service\VidService.class]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.doly.jproject.service.VidService]: Constructor threw exception; nested exception is java.lang.NullPointerException
      at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:334)
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1210)
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537)
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)
      at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303)
      at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
      at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)
      at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
      at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:755)
      at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:757)
      at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:480)
      at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:403)
      at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:306)
      at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:106)
      at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:5014)
      at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5528)
      at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
      at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1575)
      at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1565)
      at java.util.concurrent.FutureTask.run(FutureTask.java:266)
      at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
      at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
      at java.lang.Thread.run(Thread.java:745)
  Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: private com.doly.jproject.service.VidService com.doly.jproject.controllers.HomeController.vidService; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'vidService' defined in file [F:\Spring Workspace\.metadata\.plugins\org.eclipse.wst.server.core\tmp0\wtpwebapps\jobsnetwork\WEB-INF\classes\com\doly\jproject\service\VidService.class]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.doly.jproject.service.VidService]: Constructor threw exception; nested exception is java.lang.NullPointerException
      at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:561)
      at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88)
      at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:331)
      ... 22 more
  Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: private com.doly.jproject.service.VidService com.doly.jproject.controllers.HomeController.vidService; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'vidService' defined in file [F:\Spring Workspace\.metadata\.plugins\org.eclipse.wst.server.core\tmp0\wtpwebapps\jobsnetwork\WEB-INF\classes\com\doly\jproject\service\VidService.class]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.doly.jproject.service.VidService]: Constructor threw exception; nested exception is java.lang.NullPointerException
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:1101)
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1046)
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:504)
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)
      at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303)
      at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
      at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)
      at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
      at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:1120)
      at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1044)
      at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:942)
      at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:533)
      ... 24 more
  Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.doly.jproject.service.JobService]: Constructor threw exception; nested exception is java.lang.NullPointerException
      at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:163)
      at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:89)
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:1094)
      ... 35 more
  Caused by: java.lang.NullPointerException
      at com.doly.jproject.service.VidService.&lt;init&gt;(VidService.java:42)
      at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
      at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
      at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
      at java.lang.reflect.Constructor.newInstance(Constructor.java:422)
      at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:147)
      ... 37 more
  </code></pre>
  
  <p>and <code>com.doly.jproject.service.VidService.&lt;init&gt;(VidService.java:42)</code> is </p>
  
  <p>and </p>
  
  <pre><code>public void updateJobCategory(Video video) {
          Video video = (Video)session.get(Video.class, id);// Here it causes com.doly.jproject.service.VidService.&lt;init&gt;(VidService.java:42)
  video.getCustomers().clear();//removes all the existing customers
  Customer customer1 = new Customer();
  customer1.getVideos().add(video)//adding video to the customer
  video.getCustomers().add(customer1);
  session.update(video)
  
  
      }
  </code></pre>
  
  <p><strong>UPDATE</strong>
  When I change </p>
  
  <pre><code>@Autowired
      @Qualifier(value = "entityManager")
      private EntityManager entityManager;    
      private Session session;
  </code></pre>
  
  <p>and in update method I write</p>
  
  <pre><code>public void updateJobCategory(Video video) {
      session= entityManager.unwrap(org.hibernate.Session.class);
      Video video = (Video)session.get(Video.class, id);
      video.getCustomers().clear();//removes all the existing customers
      Customer customer1 = new Customer();
      customer1.getVideos().add(video)//adding video to the customer
      video.getCustomers().add(customer1);
      session.update(video)
  
  
          }
  </code></pre>
  
  <p>I get </p>
  
  <pre><code>SEVERE: Exception sending context initialized event to listener instance of class org.springframework.web.context.ContextLoaderListener
  org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'homeController': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private com.doly.jproject.service.VidService com.doly.jproject.controllers.HomeController.vidService; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'vidService': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private com.doly.jproject.repository.VidRepository com.doly.jproject.VidService.vidRepository; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'vidRepository': Cannot create inner bean '(inner bean)#681afbff' of type [org.springframework.orm.jpa.SharedEntityManagerCreator] while setting bean property 'entityManager'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#681afbff': Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [javax.persistence.EntityManager]: Factory method 'createSharedEntityManager' threw exception; nested exception is java.lang.NullPointerException
      at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:334)
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1210)
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537)
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)
      at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303)
      at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
      at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)
      at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
      at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:755)
      at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:757)
      at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:480)
      at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:403)
      at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:306)
      at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:106)
      at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:5014)
      at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5528)
      at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
      at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1575)
      at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1565)
      at java.util.concurrent.FutureTask.run(FutureTask.java:266)
      at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
      at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
      at java.lang.Thread.run(Thread.java:745)
  Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: private com.doly.jproject.service.VidService com.doly.jproject.controllers.HomeController.vidService; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'vidService': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private com.doly.jproject.repository.VidRepository com.doly.jproject.service.VidService.vidRepository; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'vidRepository': Cannot create inner bean '(inner bean)#681afbff' of type [org.springframework.orm.jpa.SharedEntityManagerCreator] while setting bean property 'entityManager'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#681afbff': Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [javax.persistence.EntityManager]: Factory method 'createSharedEntityManager' threw exception; nested exception is java.lang.NullPointerException
      at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:561)
      at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88)
      at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:331)
      ... 22 more
  Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'vidService': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private com.rhcloud.jobsnetwork.repository.JobRepository com.doly.jproject.service.VidService.vidRepository; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'vidRepository': Cannot create inner bean '(inner bean)#681afbff' of type [org.springframework.orm.jpa.SharedEntityManagerCreator] while setting bean property 'entityManager'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#681afbff': Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [javax.persistence.EntityManager]: Factory method 'createSharedEntityManager' threw exception; nested exception is java.lang.NullPointerException
      at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:334)
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1210)
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537)
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)
      at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303)
      at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
      at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)
      at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
      at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:1120)
      at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1044)
      at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:942)
      at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:533)
      ... 24 more
  Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: private com.doly.jproject.repository.VidRepository com.doly.jproject.service.VidService.vidRepository; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'vidRepository': Cannot create inner bean '(inner bean)#681afbff' of type [org.springframework.orm.jpa.SharedEntityManagerCreator] while setting bean property 'entityManager'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#681afbff': Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [javax.persistence.EntityManager]: Factory method 'createSharedEntityManager' threw exception; nested exception is java.lang.NullPointerException
      at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:561)
      at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88)
      at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:331)
      ... 35 more
  Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'vidRepository': Cannot create inner bean '(inner bean)#681afbff' of type [org.springframework.orm.jpa.SharedEntityManagerCreator] while setting bean property 'entityManager'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#681afbff': Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [javax.persistence.EntityManager]: Factory method 'createSharedEntityManager' threw exception; nested exception is java.lang.NullPointerException
      at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveInnerBean(BeanDefinitionValueResolver.java:313)
      at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:129)
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1477)
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1222)
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537)
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)
      at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303)
      at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
      at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)
      at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
      at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:1120)
      at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1044)
      at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:942)
      at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:533)
      ... 37 more
  Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#681afbff': Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [javax.persistence.EntityManager]: Factory method 'createSharedEntityManager' threw exception; nested exception is java.lang.NullPointerException
      at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:599)
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1119)
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1014)
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:504)
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)
      at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveInnerBean(BeanDefinitionValueResolver.java:299)
      ... 50 more
  Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [javax.persistence.EntityManager]: Factory method 'createSharedEntityManager' threw exception; nested exception is java.lang.NullPointerException
      at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:189)
      at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:588)
      ... 55 more
  Caused by: java.lang.NullPointerException
      at org.springframework.orm.jpa.SharedEntityManagerCreator$SharedEntityManagerInvocationHandler.initProxyClassLoader(SharedEntityManagerCreator.java:198)
      at org.springframework.orm.jpa.SharedEntityManagerCreator$SharedEntityManagerInvocationHandler.&lt;init&gt;(SharedEntityManagerCreator.java:190)
      at org.springframework.orm.jpa.SharedEntityManagerCreator.createSharedEntityManager(SharedEntityManagerCreator.java:162)
      at org.springframework.orm.jpa.SharedEntityManagerCreator.createSharedEntityManager(SharedEntityManagerCreator.java:119)
      at org.springframework.orm.jpa.SharedEntityManagerCreator.createSharedEntityManager(SharedEntityManagerCreator.java:91)
      at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
      at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
      at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
      at java.lang.reflect.Method.invoke(Method.java:497)
      at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:162)
      ... 56 more
  </code></pre>
  
  <p>How can I get an of of <code>org.hibernate.Session</code> from <code>javax.persistence.EntityManager</code> in my @Service class? please help!</p>