I am developing an application to help my office track and manage reviews. In the application, I am using JPA 2.0 with Hibernate 3.6.3 as my underlying provider. I am also using spring to inject the persistence context into my DAO. I have built the domain such that there is a Review, a Participant and a Role Entity.
The problem I am having is when I get a Review from the Entity Manager there are duplicate copies of the same Participant(i.e. same ID) in the list of participants if the Participant has more than one Role. I have also found the number of duplicates is directly related to the number Roles (i.e. if the a Participant has 3 Roles then the Participant occurs 3 times in the Review's list of participants)
I have used straight Hibernate before but this is my first time using JPA so I am sure I have configured something wrong. I just don't know what it is.
Here is the code:
Review:
@Entity
public class Review extends BaseModel{
@ManyToOne(cascade=CascadeType.ALL, fetch=FetchType.EAGER, optional=false)
private Item item;
@Column(name="ISNEW", nullable=false)
private boolean isNew;
@Enumerated(EnumType.STRING)
@Column(name="STATUS", nullable=false)
private ReviewStatus status;
@Enumerated(EnumType.STRING)
@Column(name="PHASE", nullable=false)
private Phase phase;
@Enumerated(EnumType.STRING)
@Column(name="REVIEW_TYPE", nullable=false)
private ReviewType reviewType;
@OneToMany( cascade=CascadeType.ALL, fetch=FetchType.EAGER)
private List<Participant> participants;
@OneToMany(cascade=CascadeType.ALL)
private List<Defect> defects;
@Column(name="START_DATE", nullable=false)
private Date startDate;
@Column(name="MEETING_DATE", nullable=false)
private Date meetingDate;
@Column(name="FINISH_DATE")
private Date finishDate;
@Column(name="DURATION", nullable=false)
private Double duration;
public Item getItem()
{
return item;
}
public void setItem(Item item)
{
this.item = item;
}
public List<Participant> getParticipants() {
return participants;
}
public void setParticipants(List<Participant> participants) {
this.participants = participants;
}
public List<Defect> getDefects() {
return defects;
}
public void setDefects(List<Defect> defects) {
this.defects = defects;
}
public boolean isNew() {
return isNew;
}
public void setNew(boolean isNew) {
this.isNew = isNew;
}
public Phase getPhase() {
return phase;
}
public void setPhase(Phase phase) {
this.phase = phase;
}
public Double getDuration() {
return duration;
}
public void setDuration(Double duration) {
this.duration = duration;
}
public ReviewStatus getStatus() {
return status;
}
public void setStatus(ReviewStatus status) {
this.status = status;
}
public Date getStartDate() {
return startDate;
}
public void setStartDate(Date startDate) {
this.startDate = startDate;
}
public Date getMeetingDate() {
return meetingDate;
}
public void setMeetingDate(Date meetingDate) {
this.meetingDate = meetingDate;
}
public Date getFinishDate() {
return finishDate;
}
public void setFinishDate(Date finishDate) {
this.finishDate = finishDate;
}
public ReviewType getReviewType()
{
return reviewType;
}
public void setReviewType(ReviewType reviewType)
{
this.reviewType = reviewType;
}
}
Participant:
@Entity
public class Participant extends BaseModel{
private Double inspectionTime;
@ManyToOne(cascade=CascadeType.ALL, optional=false)
private Person person;
@ManyToMany(cascade=CascadeType.ALL, fetch=FetchType.EAGER )
private Set<Role> roles;
public Double getInspectionTime() {
return inspectionTime;
}
public void setInspectionTime(Double preInspectionTime) {
this.inspectionTime = preInspectionTime;
}
public Person getPerson() {
return person;
}
public void setPerson(Person person) {
this.person = person;
}
public Set<Role> getRoles() {
return roles;
}
public void setRoles(Set<Role> roles) {
this.roles = roles;
}
}
Role:
@Entity
public class Role extends BaseModel{
@Column(nullable=false, unique=true)
private String name;
private String responsiblity;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getResponsiblity() {
return responsiblity;
}
public void setResponsiblity(String responsiblity) {
this.responsiblity = responsiblity;
}
}
Base:
@MappedSuperclass
public abstract class BaseModel {
@Id
@GeneratedValue
private Long id;
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
}
DataAccessObject which uses the entityManager:
@Transactional(readOnly = false, propagation = Propagation.REQUIRED)
public class ReviewDaoJpaImpl implements ReviewDao
{
@PersistenceContext
private EntityManager em;
public Review getReviewById(Long id)
{
return em.find(Review.class, id);
}
}
Call which receives duplicates:
Review review = reviewDao.getReviewById(1776L);
List<Participant> participants = review.getParticipants();
for (Participant participant : participants)
{
System.out.println(participant.getPerson().getName());
}
