Architecture to Avoid Hibernate LazyInitializationExceptions

I am at the beginning of my project. So I am trying to create an architecture that avoids Hibernate LazyInitializationExceptions exceptions. So far, my Context.xml application has:

<bean id="sessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
    <property name="dataSource" ref="dataSource"/>
    <property name="configLocation">
        <value>/WEB-INF/hibernate.cfg.xml</value>
    </property>
    <property name="configurationClass">
        <value>org.hibernate.cfg.AnnotationConfiguration</value>
    </property>        
    <property name="hibernateProperties">
        <props>
            <prop key="hibernate.dialect">${hibernate.dialect}</prop>        
            <prop key="hibernate.show_sql">${hibernate.show_sql}</prop>     
        </props>
    </property>
    <property name="eventListeners">
        <map>
            <entry key="merge">
                <bean class="org.springframework.orm.hibernate3.support.IdTransferringMergeEventListener"/>
            </entry>
        </map>
    </property>
</bean>

<bean id="dao" class="info.ems.hibernate.HibernateEMSDao" init-method="createSchema">
    <property name="hibernateTemplate">
        <bean class="org.springframework.orm.hibernate3.HibernateTemplate">
            <property name="sessionFactory" ref="sessionFactory"/>
            <property name="flushMode">
                <bean id="org.springframework.orm.hibernate3.HibernateAccessor.FLUSH_COMMIT" class="org.springframework.beans.factory.config.FieldRetrievingFactoryBean"/>                    
            </property>
        </bean>
    </property>        
    <property name="schemaHelper">
        <bean class="info.ems.hibernate.SchemaHelper">                                
            <property name="driverClassName" value="${database.driver}"/>
            <property name="url" value="${database.url}"/>
            <property name="username" value="${database.username}"/>
            <property name="password" value="${database.password}"/>
            <property name="hibernateDialect" value="${hibernate.dialect}"/>   
            <property name="dataSourceJndiName" value="${database.datasource.jndiname}"/>
        </bean>                
    </property>
</bean>       

Hibernate.cfg.xml file:

<hibernate-configuration>
    <session-factory>       
        <mapping class="info.ems.models.User" />
        <mapping class="info.ems.models.Role" />
    </session-factory>
</hibernate-configuration>

The Role.java:

@Entity
@Table(name="ROLE")
@Access(AccessType.FIELD)
public class Role implements Serializable {

    private static final long serialVersionUID = 3L;

    @Id
    @Column(name="ROLE_ID", updatable=false, nullable=false)
    @GeneratedValue(strategy = GenerationType.IDENTITY) 
    private long id;

    @Column(name="USERNAME")
    private String username;

    @Column(name="ROLE")
    private String role;

    public long getId() {
        return id;
    }

    public void setId(long id) {
        this.id = id;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getRole() {
        return role;
    }

    public void setRole(String role) {
        this.role = role;
    }
}

And User.java:

@Entity
@Table(name = "USER")
@Access(AccessType.FIELD)
public class User implements UserDetails, Serializable {

    private static final long serialVersionUID = 2L;

    @Id
    @Column(name = "USER_ID", updatable=false, nullable=false)
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private long id;

    @Column(name = "USERNAME")
    private String username;

    @Column(name = "PASSWORD")
    private String password;

    @Column(name = "NAME")
    private String name;

    @Column(name = "EMAIL")
    private String email;

    @Column(name = "LOCKED")
    private boolean locked;

    @OneToMany(cascade = CascadeType.ALL, fetch = FetchType.EAGER, targetEntity = Role.class)
    @JoinTable(name = "USER_ROLE", joinColumns = { @JoinColumn(name = "USER_ID") }, inverseJoinColumns = { @JoinColumn(name = "ROLE_ID") })
    private Set<Role> roles;

    @Override
    public GrantedAuthority[] getAuthorities() {
        List<GrantedAuthorityImpl> list = new ArrayList<GrantedAuthorityImpl>(0);
        for (Role role : roles) {
            list.add(new GrantedAuthorityImpl(role.getRole()));
        }
        return (GrantedAuthority[]) list.toArray(new GrantedAuthority[list.size()]);
    }

    @Override
    public boolean isAccountNonExpired() {
        return true;
    }

    @Override
    public boolean isAccountNonLocked() {
        return !isLocked();
    }

    @Override
    public boolean isCredentialsNonExpired() {
        return true;
    }

    @Override
    public boolean isEnabled() {
        return true;
    }

    public long getId() {
        return id;
    }

    public void setId(long id) {
        this.id = id;
    }

    @Override
    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    @Override
    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public boolean isLocked() {
        return locked;
    }

    public void setLocked(boolean locked) {
        this.locked = locked;
    }

    public Set<Role> getRoles() {
        return roles;
    }

    public void setRoles(Set<Role> roles) {
        this.roles = roles;
    }
}

HibernateEMSDao has two methods for saving and loading a user from a database:

public void saveUser(final User user) {     
    getHibernateTemplate().execute(new HibernateCallback() {

        @Override
        public Object doInHibernate(Session session) throws HibernateException, SQLException {
            session.flush();
            session.setCacheMode(CacheMode.IGNORE);
            session.save(user);
            session.flush();
            return null;
        }
    });     
}

public User getUser(final Long id) {
    return (User) getHibernateTemplate().execute(new HibernateCallback() {

        @Override
        public Object doInHibernate(Session session) throws HibernateException, SQLException {
            return session.get(User.class, id);
        }
    });
}

Now I tested that if I implement HibernateEMSDao#getUseras:

public User getUser(final Long id) {
    getHibernateTemplate().load(User.class, id);        
}

I get a LazyInitializationExcaption - the session is closed. But the first way works fine. Therefore, I need to suggest avoiding this exception in the near future. Any small piece of information is noticeable.

Thank you and welcome.

Note. I got this error after rebooting my server.

Edit: code added:

public void saveUser(final User user) {     
    Session session = getSession();
    Transaction transaction = session.beginTransaction();
    session.save(user);
    transaction.commit();
    session.close();
}
public User getUser(final Long id) {
    Session session = getSession();
    session.enableFetchProfile("USER-ROLE-PROFILE");
    User user = (User) session.get(User.class, id);
    session.disableFetchProfile("USER-ROLE-PROFILE");
    session.close();
    return user;
}
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