I have the below mentioned Entity classes, when I execute my application I am getting the following exception. Some of the other similar questions didn't solve the problem.
WARNING: StandardWrapperValve[jersey-serlvet]: PWC1406: Servlet.service()
for servlet jersey-serlvet threw exception
org.hibernate.LazyInitializationException: failed to lazily initialize
a collection of role: test.entity.Dept.empDeptno, no session
or session was closed
at org.hibernate.collection.internal.AbstractPersistentCollection.
throwLazyInitializationException(AbstractPersistentCollection.java:393)
at org.hibernate.collection.internal.AbstractPersistentCollection.
throwLazyInitializationExceptionIfNotConnected
(AbstractPersistentCollection.java:385)
at org.hibernate.collection.internal.AbstractPersistentCollection.
initialize(AbstractPersistentCollection.java:378)
How can I solve this issue?
Emp Entity
@Entity
@Table(name = "EMP", schema = "SCOTT"
)
@XmlRootElement
@NamedQueries({
@NamedQuery(name = "Emp.findAllEmployees", query = "select e from Emp e left
join fetch e.deptNo order by e.empno desc")
})
public class Emp implements java.io.Serializable {
@Id
@Column(name = "EMPNO", unique = true, nullable = false, precision = 4,
scale = 0)
private short empno;
@ManyToOne
@JoinColumn(name = "DEPTNO", referencedColumnName = "DEPTNO")
private Dept deptNo;
Dept Entity
@Entity
@Table(name = "DEPT", schema = "SCOTT"
)
@XmlRootElement
public class Dept implements java.io.Serializable {
@Id
@Column(name = "DEPTNO", unique = true, nullable = false, precision = 2,
scale = 0)
private short deptno;
@OneToMany(fetch=FetchType.LAZY,mappedBy = "deptNo")
private Set<Emp> empDeptno;
DAOImpl
@Override
public List<Emp> findAllEmployees() {
return getEntityManager().createNamedQuery("Emp.findAllEmployees",
Emp.class).getResultList();
}
Jersey RESTful service
@Component
@Path("/employee")
public class EmployeeRestService {
@Autowired
EmployeeService employeeService;
@GET
@Produces({MediaType.APPLICATION_JSON})
public List<Emp> getEmployees() {
List<Emp> emp = new ArrayList<Emp>();
emp.addAll(getEmployeeService().findAllEmployees());
return emp;
}
Spring applicationContext.xml
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-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/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd"
>
<!-- Data Source Declaration -->
<bean id="DataSource" class="org.springframework.jndi.JndiObjectFactoryBean">
<property name="jndiName" value="jdbc/scottDS"/>
</bean>
<context:component-scan base-package="net.test" />
<bean class="org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor"/>
<bean id="entityManagerFactory"
class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
<property name="dataSource" ref="DataSource" />
<property name="packagesToScan" value="net.test" />
<property name="jpaVendorAdapter">
<bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
<property name="showSql" value="false" />
<property name="generateDdl" value="false" />
<property name="databasePlatform" value="${jdbc.dialectClass}" />
</bean>
</property>
</bean>
<bean id="defaultLobHandler" class="org.springframework.jdbc.support.lob.DefaultLobHandler" />
<!-- Transaction Config -->
<bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
<property name="entityManagerFactory" ref="entityManagerFactory" />
</bean>
<tx:annotation-driven transaction-manager="transactionManager"/>
<context:annotation-config/>
<bean id="hibernateStatisticsMBean" class="org.hibernate.jmx.StatisticsService">
<property name="statisticsEnabled" value="true" />
<property name="sessionFactory" value="#{entityManagerFactory.sessionFactory}" />
</bean>
</beans>
I have resolved the issue by adding the following in web.xml
<filter>
<filter-name>OpenEntityManagerInViewFilter</filter-name>
<filter-class>org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>OpenEntityManagerInViewFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
courtesy here and here
Thanks
The problem is that the scope of your database/JPA transaction only contains the service (which I assume is a stateless session bean) and does NOT contain the REST resource bean.
List<Emp>
and accesses field empDeptno
.So when Jersey gets the list of Emp
to produce XML out of it, the transaction has already been closed. When now the field empDeptNo
is navigated, JPA tries to lazily load it, which fails as we're already outside a valid transaction/session.
You might try to extend the transaction scope to also contain your Jersey REST resource bean by making a stateless session bean out of it. Then it might be as follows:
List<Emp>
and accesses field empDeptno
.I'm not 100% sure, it might also be that step 8 comes BEFORE step 7, so the transaction might be closed before the producer does its job. If that's the case, this solution is simply wrong...
But I think you should simply try it...
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