Fala pessoal gostaria da ajuda de vocês. Estou fazendo um pequeno projeto com Hibernate e Spring. Estou enfrentando uma LazyInitializationException sempre que tento acessar os atributos Lazy dos objetos no JSP ou no servlet. Eu adotei o filtro OpenSessionInViewFilter mas mesmo assim a exceção é lançada. Eu entendo que de alguma forma a sessão está sendo fechada mas não sei como evitar isso. Abaixo estou postando a exceção, o aplicationContext.xml, o web.xml e algumas classes. Essencialmente são duas entidade com relação Many To One e One To Many com Lazy Fetching.
org.apache.jasper.JasperException: javax.el.ELException: Error reading 'userList' on type com.vh.lab.entities.School_$$_javassist_0
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:491)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:419)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
com.vh.lab.servlets.UserServlet.doGet(UserServlet.java:38)
javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:198)
org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
root cause
javax.el.ELException: Error reading 'userList' on type com.vh.lab.entities.School_$$_javassist_0
javax.el.BeanELResolver.getValue(BeanELResolver.java:66)
javax.el.CompositeELResolver.getValue(CompositeELResolver.java:54)
org.apache.el.parser.AstValue.getValue(AstValue.java:118)
org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:186)
org.apache.jasper.runtime.PageContextImpl.proprietaryEvaluate(PageContextImpl.java:935)
org.apache.jsp.index_jsp._jspx_meth_c_005fforEach_005f0(index_jsp.java:110)
org.apache.jsp.index_jsp._jspService(index_jsp.java:82)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:377)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
com.vh.lab.servlets.UserServlet.doGet(UserServlet.java:38)
javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:198)
org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
root cause
org.hibernate.LazyInitializationException: could not initialize proxy - no Session
org.hibernate.proxy.AbstractLazyInitializer.initialize(AbstractLazyInitializer.java:167)
org.hibernate.proxy.AbstractLazyInitializer.getImplementation(AbstractLazyInitializer.java:215)
org.hibernate.proxy.pojo.javassist.JavassistLazyInitializer.invoke(JavassistLazyInitializer.java:190)
com.vh.lab.entities.School_$$_javassist_0.getUserList(School_$$_javassist_0.java)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
java.lang.reflect.Method.invoke(Unknown Source)
javax.el.BeanELResolver.getValue(BeanELResolver.java:62)
javax.el.CompositeELResolver.getValue(CompositeELResolver.java:54)
org.apache.el.parser.AstValue.getValue(AstValue.java:118)
org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:186)
org.apache.jasper.runtime.PageContextImpl.proprietaryEvaluate(PageContextImpl.java:935)
org.apache.jsp.index_jsp._jspx_meth_c_005fforEach_005f0(index_jsp.java:110)
org.apache.jsp.index_jsp._jspService(index_jsp.java:82)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:377)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
com.vh.lab.servlets.UserServlet.doGet(UserServlet.java:38)
javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:198)
org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
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"
xmlns:tx="http://www.springframework.org/schema/tx"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop-3.0.xsd">
<tx:annotation-driven/>
<bean id="txManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager">
<property name="sessionFactory" ref="sessionFactory"/>
</bean>
<bean id="userService" class="com.vh.lab.service.impl.UserServiceImpl">
<property name="schoolDao" ref="schoolDao"/>
<property name="userDao" ref="userDao"/>
</bean>
<bean id="userDao" class="com.vh.lab.dao.impl.UserDaoImpl">
<property name="sessionFactory" ref="sessionFactory" />
</bean>
<bean id="schoolDao" class="com.vh.lab.dao.impl.SchoolDaoImpl">
<property name="sessionFactory" ref="sessionFactory" />
</bean>
<tx:advice id="txAdvice" transaction-manager="txManager">
<tx:attributes>
<tx:method name="get*" propagation="REQUIRES_NEW" read-only="true"/>
<tx:method name="*"/>
</tx:attributes>
</tx:advice>
<aop:config>
<aop:pointcut id="ServiceOperation" expression="execution(* com.vh.lab.service.impl.*.*(..))"/>
<aop:advisor advice-ref="txAdvice" pointcut-ref="ServiceOperation"/>
</aop:config>
<bean id="dataSource"
class="org.apache.commons.dbcp.BasicDataSource"
destroy-method="close">
<property name="url">
<value>jdbc:mysql://localhost/test</value>
</property>
<property name="username">
<value>vh</value>
</property>
<property name="password">
<value>pass</value>
</property>
<property name="driverClassName">
<value>com.mysql.jdbc.Driver</value>
</property>
<property name="initialSize">
<value>5</value>
</property>
<property name="maxActive">
<value>20</value>
</property>
<property name="maxIdle">
<value>5</value>
</property>
<property name="poolPreparedStatements">
<value>true</value>
</property>
</bean>
<bean id="sessionFactory"
class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean">
<property name="dataSource">
<ref local="dataSource" />
</property>
<property name="annotatedClasses">
<list>
<value>com.vh.lab.entities.User</value>
<value>com.vh.lab.entities.School</value>
</list>
</property>
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">org.hibernate.dialect.MySQL5InnoDBDialect</prop>
<prop key="show_sql">true</prop>
<prop key="hibernate.generate_statistics">true</prop>
<prop key="hibernate.use_sql_comments">true</prop>
<prop key="hibernate.hbm2ddl.auto">create-drop</prop>
<prop key="hibernate.show_sql">true</prop>
</props>
</property>
</bean>
</beans>
web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:jsp="http://java.sun.com/xml/ns/javaee/jsp" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5">
<display-name>SpringLab</display-name>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:/applicationContext.xml</param-value>
</context-param>
<listener>
<listener-class>com.vh.lab.listeners.AppContextListener</listener-class>
</listener>
<servlet>
<description></description>
<display-name>UserServlet</display-name>
<servlet-name>UserServlet</servlet-name>
<servlet-class>com.vh.lab.servlets.UserServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>UserServlet</servlet-name>
<url-pattern>/user/*</url-pattern>
</servlet-mapping>
<filter>
<filter-name>OpenSessionInViewFilter</filter-name>
<filter-class>org.springframework.orm.hibernate3.support.OpenSessionInViewFilter</filter-class>
<init-param>
<param-name>singleSession</param-name>
<param-value>true</param-value>
</init-param>
<init-param>
<param-name>sessionFactoryBeanName</param-name>
<param-value>sessionFactory</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>OpenSessionInViewFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<jsp-config>
<taglib>
<taglib-uri>http://java.sun.com/jstl/core</taglib-uri>
<taglib-location>/WEB-INF/c.tld</taglib-location>
</taglib>
<taglib>
<taglib-uri>http://java.sun.com/jstl/fmt</taglib-uri>
<taglib-location>/WEB-INF/fmt.tld</taglib-location>
</taglib>
</jsp-config>
</web-app>
Trecho do jsp (index.jsp) – Aqui é lançada a exceção
<c:forEach var="user" items="${school.userList}">
<c:out value="${user.firstName}"></c:out>
</c:forEach>
Entidades - School.java e User.java
@Data
@Entity
public class School {
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private Integer id;
private String Name;
@OneToMany(mappedBy = "school")
private List<User> userList;
//getter and setters
@Transactional
public List<User> getUserList(){
return userList;
}
}
@Data
@Entity
public class User {
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private Integer id;
private String firstName;
@ManyToOne
private School school;
//getter and setters
}
UserServiceImpl.java
public class UserServiceImpl implements UserService{
private SchoolDao schoolDao;
private UserDao userDao;
public void setUserDao(UserDao userDao) {
this.userDao = userDao;
}
public void setSchoolDao(SchoolDao schoolDao) {
this.schoolDao = schoolDao;
}
@Override
public void addUser() {
School school = new School();
school.setName("Grupo1");
schoolDao.save(school);
School school2 = new School();
school2.setName("Grupo2");
schoolDao.save(school2);
School school3 = new School();
school3.setName("Grupo3");
schoolDao.save(school3);
User user = new User();
user.setSchool(school2);
user.setFirstName("vh1");
userDao.save(user);
User user2 = new User();
user2.setSchool(school2);
user2.setFirstName("vh2");
userDao.save(user2);
}
public School getUserFromSchool(){
School school = schoolDao.load(School.class, new Integer(2));
return school;
}
}
Dao - UserDaoImpl.java
public class GenericDao<T> extends HibernateDaoSupport implements Dao<T> {
@Override
public List<T> listAll(Class clazz) {
return getHibernateTemplate().loadAll(clazz);
}
@Override
public T load(Class clazz, Serializable id) {
return (T) getHibernateTemplate().load(clazz, id);
}
@Override
public void save(T object) {
getHibernateTemplate().save(object);
}
}
public class UserDaoImpl extends GenericDao<User> implements UserDao {
@Override
public void saveOrUpdate(User user) {
getHibernateTemplate().saveOrUpdate(user);
}
}
Servlet - UserServlet.java
public class UserServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
public UserServlet() {
super();
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
UserService userService = (UserService) AppContextListener.ctx.getBean("userService");
userService.addUser();
School school = userService.getUserFromSchool();
request.setAttribute("school", school);
request.getRequestDispatcher("/index.jsp").forward(request, response);
}
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
}
}
O problema ocorre quando chamo o servlet e este envia a requisição para o JSP. A aplicação falha ao tentar buscar os atributos do objeto de tipo School. Quem puder ajudar desde já eu agradeço.