Excerpt from sdms/simple-spring-mvc/simple-spring-mvc-person/src/main/java/org/springbyexample/sdms/simpleForm/orm/bean/Person.java

                    
@Entity
@Table(name="PERSON")
public class Person implements Comparable<Person>, Serializable {

    ...
    
    private Integer id = null;
    private String firstName = null;
    private String lastName = null;
    private Set<Address> addresses = null;
    private Date created = null;
    
    /**
     * Gets id (primary key).
     */
    @Id
    @GeneratedValue(strategy=GenerationType.AUTO)
    public Integer getId() {
        return id;
    }

    /**
     * Sets id (primary key).
     */
    public void setId(Integer id) {
        this.id = id;
    }
    
    /**
     * Gets first name.
     */
    @Column(name="FIRST_NAME")
    public String getFirstName() {
        return firstName;
    }

    /**
     * Sets first name.
     */
    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }
    
    /**
     * Gets last name.
     */
    @Column(name="LAST_NAME")
    public String getLastName() {
        return lastName;
    }
    
    /**
     * Sets last name.
     */
    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

    /**
     * Gets list of <code>Address</code>es.
     */
    @OneToMany(fetch=FetchType.EAGER, cascade=CascadeType.ALL)
    @JoinColumn(name="PERSON_ID", nullable=false)
	public Set<Address> getAddresses() {
		return addresses;
	}

    /**
     * Sets list of <code>Address</code>es.
     */
	public void setAddresses(Set<Address> addresses) {
		this.addresses = addresses;
	}

    /**
     * Gets date created.
     */
	public Date getCreated() {
		return created;
	}

    /**
     * Sets date created.
     */
	public void setCreated(Date created) {
		this.created = created;
	}
	
	public Address findAddressById(Integer id) {
	    Address result = null;
	    
	    if (addresses != null) {
	        for (Address address: addresses) {
	            if (address.getId().equals(id)) {
	                result = address;
	                
	                break;
	            }
	        }
	    }
	    
	    return result;
	}
	
    ...

}
                    
                

                    
@Repository("personDao")
@Transactional(readOnly = true)
public class PersonDaoImpl implements PersonDao {

    private EntityManager em;

    @PersistenceContext
    public void setEntityManager(EntityManager em) {
        this.em = em;
    }
    
    /**
     * Find persons.
     */
    @SuppressWarnings("unchecked")
    public Person findPersonById(Integer id) {
        return em.find(Person.class, id);
    }
    
    /**
     * Find persons using a start index and max number of results.
     */
    @SuppressWarnings("unchecked")
    public Collection<Person> findPersons(final int startIndex, final int maxResults) {
        return em.createQuery("select p from Person p order by p.lastName, p.firstName")
            .setFirstResult(startIndex).setMaxResults(maxResults).getResultList();
    }

    /**
     * Find persons.
     */
    @SuppressWarnings("unchecked")
    public Collection<Person> findPersons() {
        return em.createQuery("select p from Person p order by p.lastName, p.firstName").getResultList();
    }

    /**
     * Find persons by last name.
     */
    @SuppressWarnings("unchecked")
    public Collection<Person> findPersonsByLastName(String lastName) {
        return em.createQuery("select p from Person p where p.lastName = :lastName order by p.lastName, p.firstName")
            .setParameter("lastName", lastName).getResultList();
    }
    
    /**
     * Saves person.
     */
    @Transactional(readOnly = false, propagation = Propagation.REQUIRES_NEW)
    public Person save(Person person) {
        return em.merge(person);
    }

    /**
     * Deletes person.
     */
    @Transactional(readOnly = false, propagation = Propagation.REQUIRES_NEW)
    public void delete(Person person) {
        em.remove(em.merge(person));
    }

    /**
     * Saves address to person.
     */
    @Transactional(readOnly = false, propagation = Propagation.REQUIRES_NEW)
    public Person saveAddress(Integer id, Address address) {
        Person person = findPersonById(id);

        if (person.getAddresses().contains(address)) {
            person.getAddresses().remove(address);
        }
        
        person.getAddresses().add(address);
        
        return save(person);
    }
    
    /**
     * Deletes address from person.
     */
    @Transactional(readOnly = false, propagation = Propagation.REQUIRES_NEW)
    public Person deleteAddress(Integer id, Integer addressId) {
        Person person = findPersonById(id);
        
        Address address = new Address();
        address.setId(addressId);
        
        if (person.getAddresses().contains(address)) {
            person.getAddresses().remove(address);
        }
        
        return save(person);
    }
    
}