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POEntityManager is null in DAO class
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I'm trying to build an application with Java Spring and hibernate. For the dao classes I'm using the generic dao pattern. When I try to execute a query a nullpointer exception is thrown because the entityManager is null. I think it's not injected properly but I don't know why. Application context: <pre><code><?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:p="http://www.springframework.org/schema/p" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx" 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 http://www.springframework.org/schema/aop/spring-aop-3.1.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.1.xsd"> <bean id = "klantDao" class="service.JpaKlantDao"/> <bean id="userDao" class="service.JpaUserDao"/> <bean id="assembler" class="service.Assembler" /> </beans> </code></pre> Dispatcher servlet: <pre><code><?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:p="http://www.springframework.org/schema/p" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx" xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:context="http://www.springframework.org/schema/context" xmlns:jee="http://www.springframework.org/schema/jee" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-3.0.xsd"> <mvc:annotation-driven /> <context:component-scan base-package="controllers"/> <context:component-scan base-package="service"/> <mvc:resources mapping="/resources/**" location="/resources/" /> <jee:jndi-lookup id="dataSource" jndi-name="jdbc/CentricJavaDB"/> <bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean"> <property name="dataSource" ref="dataSource" /> <property name="packagesToScan"> <list> <value>domain</value> </list> </property> <property name="jpaVendorAdapter"> <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter"> <property name="showSql" value="true" /> <property name="generateDdl" value="true" /> <property name="databasePlatform" value="org.hibernate.dialect.MySQLDialect"/> </bean> </property> </bean> <bean id="transactionManager" class=" org.springframework.orm.jpa.JpaTransactionManager "> <constructor-arg ref="entityManagerFactory" /> </bean> <tx:annotation-driven transaction-manager="transactionManager" proxy-target-class="true"/> <bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver" p:prefix="/WEB-INF/jsp/" p:suffix=".jsp" /> <bean id="messageSource" class="org.springframework.context.support.ResourceBundleMessageSource"> <property name="basename" value="mymessages" /> </bean> </beans> </code></pre> Web.xml: <pre><code><?xml version="1.0" encoding="UTF-8"?> <web-app version="3.1" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"> <context-param> <param-name>contextConfigLocation</param-name> <param-value> /WEB-INF/applicationContext.xml, /WEB-INF/spring-security.xml </param-value> </context-param> <listener> <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class> </listener> <servlet> <servlet-name>dispatcher</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <load-on-startup>2</load-on-startup> </servlet> <servlet-mapping> <servlet-name>dispatcher</servlet-name> <url-pattern>*.htm</url-pattern> </servlet-mapping>  <filter> <filter-name>springSecurityFilterChain</filter-name> <filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class> </filter> <filter-mapping> <filter-name>springSecurityFilterChain</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> <session-config> <session-timeout> 30 </session-timeout> </session-config> <welcome-file-list> <welcome-file>overzicht.jsp</welcome-file> </welcome-file-list> </web-app> </code></pre> The controller where I inject the dao: <pre><code>@Controller public class LoginController { @Autowired private KlantDao klantDao; @RequestMapping(value="/login", method = RequestMethod.GET) public String klantInloggen(Model model) { String k; k = klantDao.findAll().get(0).getEmailadres(); return "login"; } } </code></pre> The generic dao interface: <pre><code>public interface GenericDao<T> { public List<T> findAll(); public T update(T object); public T get(Long id); public void delete(T object); public void insert(T object); public boolean exists(Long id) ; } </code></pre> The generic dao implementation: <pre><code>@Transactional public class JpaGenericDao<T> implements GenericDao<T> { private Class<T> type; private EntityManager em; public JpaGenericDao(Class<T> type) { super(); this.type = type; } @PersistenceContext public void setEntityManager(EntityManager em) { this.em = em; } @Transactional(readOnly = true) @Override public T get(Long id) { T entity = this.em.find(this.type, id); return entity; } @Transactional(readOnly = true) @Override public List<T> findAll() { return this.em.createQuery( "select entity from " + this.type.getName() + " entity").getResultList(); } //@Transactional @Override public void insert(T object) { em.persist(object); } //@Transactional @Override public void delete(T object) { em.remove(em.merge(object)); } @Transactional(readOnly = true) @Override public boolean exists(Long id) { T entity = this.em.find(this.type, id); return entity != null; } @Override public T update(T object) { return em.merge(object); } } </code></pre> The Klant dao interface: <pre><code>public interface KlantDao { public List<Klant> findAll(); } </code></pre> The klant dao implementation: <pre><code>public class JpaKlantDao extends JpaGenericDao<Klant> implements KlantDao { public JpaKlantDao() { super(Klant.class); } } </code></pre> I hope someone can help me, I've been debugging for hours and I can't find what I'm doing wrong.
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<java><spring><hibernate><spring-mvc><jpa>
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EntityManager is null in DAO class
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