Nested in org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'populator' defined in class path resource [spring-core.xml]: Invocation of init method failed; nested exception is org.springframework.beans.factory.BeanInitializationException: Initialization of DAO failed; nested exception is org.hibernate.HibernateException: Illegal attempt to associate a collection with two open sessions:
org.hibernate.HibernateException: Illegal attempt to associate a collection with two open sessions

    <!-- Enable annotation configuration -->
    <context:annotation-config/>

    <!-- Scan packages for Spring annotations -->
    <context:component-scan base-package="myapp.service"/>

    <bean id="sessionFactory" class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean">
        <!-- ommitted -->
    </bean>

    <!-- Transaction support beans -->
    <bean id="transactionManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager">
        <property name="sessionFactory" ref="sessionFactory"/>
    </bean>

    <bean id="hibernateTemplate" class="org.springframework.orm.hibernate3.HibernateTemplate">
        <property name="sessionFactory" ref="sessionFactory"/>
    </bean>

    <!-- Spring AOP auto-proxy creation (required to support Shiro annotations) -->
    <bean class="org.springframework.aop.framework.autoproxy.DefaultAdvisorAutoProxyCreator"/>

    <!-- Populates the database with default data. -->
    <bean id="populator" class="myapp.service.BootstrapDataPopulator">
        <property name="sessionFactory" ref="sessionFactory"/>
    </bean>

    <!-- Post processor that automatically invokes init() and destroy() methods -->
    <bean id="lifecycleBeanPostProcessor" class="org.apache.shiro.spring.LifecycleBeanPostProcessor"/>

@Transactional
public class BootstrapDataPopulator extends HibernateDaoSupport {
   
    private static final Logger log = LoggerFactory.getLogger(BootstrapDataPopulator.class);

    public void initDao() throws Exception {
      buildRolesData();
      buildMemberData();
    }
   
    private static final String[][] ROLES = {
      {"member"},
      {"manager"},
      {"admin"}
    };

    private void buildRolesData() {
       log.debug("Building Roles Data");
   for (int i = 0; i < ROLES.length; i++) {
      Role r = new Role(ROLES[i][0]);
           getSession().save(r);
   }
    }

    private static final String[][] MEMBERS = {
      {"tom","Tom","Smith"},
      {"member","Sue","Stark"},
      {"admin","Mark","Brisk"}
    };

    private static final String[][] MEMBER_ROLES = {
      {
         "member","manager"
      },
      {
         "member"
      },
      {
         "member","manager","admin"
      }
    };

    private void buildMemberData() {
       log.debug("Building Member Data");
   for (int i = 0; i < MEMBERS.length; i++) {
      Member m= new Member();
      m.setUsername(MEMBERS[i][0]);
      m.setPassword(MEMBERS[i][0]);

      for (int j = 0; j < MEMBER_ROLES[i].length; j++) {
              Role r = (Role) getSession().createCriteria(Role.class)
            .add(Restrictions.eq("name", MEMBER_ROLES[i][j]))
            .uniqueResult();
         if (r != null) {
            m.addRole(r);
         }
      }
           getSession().save(m);
   }
    }
}

@Entity
@Table(name="members")
@Cache(usage= CacheConcurrencyStrategy.READ_WRITE)
public class Member extends AbstractEntity {
    private static final long serialVersionUID = 1L;

    private String username;
    private String password;
    private Set<Role> roles = new HashSet<Role>();
   
   public Member() {
      super();
   }

    @Basic(optional=false)
    @Column(length=100)
    @Index(name="idx_members_username")
    public String getUsername() {
        return username;
    }
    public void setUsername(String username) {
        this.username = username;
    }

    @Basic(optional=false)
    @Column(length=255)
    public String getPassword() {
        return password;
    }
    public void setPassword(String password) {
        this.password = password;
    }

   @ManyToMany(cascade = CascadeType.ALL)
    @JoinTable(name="members_roles")
    @Cache(usage=CacheConcurrencyStrategy.READ_WRITE)
   public Set<Role> getRoles() {
      return this.roles;
   }
   public void setRoles(Set<Role> roles) {
      this.roles = roles;
   }
   public Role hasRole(Role role) {
      if (this.roles.contains(role)) {
         return role;
      }
      return null;
   }
   public boolean addRole(Role role) {
      return this.roles.add(role);
   }
   public boolean removeRole(Role role) {
      return this.roles.remove(role);
   }

}

@Entity
@Table(name="roles")
@Cache(usage= CacheConcurrencyStrategy.READ_WRITE)
public class Role implements Serializable {
   private static final long serialVersionUID = 1L;

    private Long id;
    private String name;

    protected Role() {
    }
    public Role(String name) {
        this.name = name;
    }

    @Id
    @GeneratedValue
    public Long getId() {
        return id;
    }
    public void setId(Long id) {
        this.id = id;
    }

    @Basic(optional=false)
    @Column(length=100)
    @Index(name="idx_roles_name")
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
}