Mapped Entity null on @OneToOne with @JoinColumn

Question

I get the mapped entity always null but, FetchType.EAGER is set already. I have a Booking entity class that maps to two other entities - Slot and Subscriber. Both the entities are null when I fetch the booking entity

Booking class

import java.util.Date;
import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.OneToOne;
import javax.persistence.Table;
import javax.persistence.Temporal;
import javax.persistence.TemporalType;
import javax.persistence.Version;


@Entity
@Table(name = "BOOKING")
public class Booking {

    public Booking(){

    }

    @Id @GeneratedValue(strategy=GenerationType.IDENTITY)
    @Column(name = "id")
    private Integer id;

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

    @Column(name = "descr")
    private String desc;


    @OneToOne(fetch=FetchType.EAGER)
    @JoinColumn(name = "slotid",insertable = false, updatable = false)
    private Slot slot;

    private Integer slotid;

    private Integer subscriberid;


    @OneToOne(fetch=FetchType.EAGER)
    @JoinColumn(name = "subscriberid",insertable = false, updatable = false)
    private User subscriber;

    @Column(name = "created")
    @Temporal(TemporalType.TIMESTAMP)
    private Date created;

    public Integer getId() {
        return id;
    }

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

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    @OneToOne(fetch=FetchType.EAGER)
    @JoinColumn(name = "slotid",referencedColumnName="slotid")
    public Slot getSlot() {
        return slot;
    }

    public void setSlot(Slot slot) {
        this.slot = slot;
    }

    @OneToOne(fetch=FetchType.EAGER)
    @JoinColumn(name = "subscriberid",referencedColumnName="userid")
    public User getSubscriber() {
        return subscriber;
    }

    public void setSubscriber(User subscriber) {
        this.subscriber = subscriber;
    }

    public Date getCreated() {
        return created;
    }

    public void setCreated(Date created) {
        this.created = created;
    }

    public String getDesc() {
        return desc;
    }

    public void setDesc(String desc) {
        this.desc = desc;
    }

    public Integer getSlotid() {
        return slotid;
    }

    public void setSlotid(Integer slotid) {
        this.slotid = slotid;
    }

    public Integer getSubscriberid() {
        return subscriberid;
    }

    public void setSubscriberid(Integer subscriberid) {
        this.subscriberid = subscriberid;
    }



}

Slot class

import java.util.Date;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.OneToOne;
import javax.persistence.Table;
import javax.persistence.Temporal;
import javax.persistence.TemporalType;
import javax.persistence.Version;

@Entity
@Table(name="SLOT")
public class Slot {

    public Slot(){

    }

    @Id @GeneratedValue(strategy=GenerationType.IDENTITY)
    @Column(name="slotid")
    private Integer id;

    @OneToOne(fetch=FetchType.EAGER)
    @JoinColumn(name="ownerid",insertable = false, updatable = false)
    private User user;

    @Column(name="startdate")
    private Date startdate;

    @Column(name="enddate")
    private Date enddate;

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

    private Integer ownerid;

    @Temporal(TemporalType.TIMESTAMP)
    @Column(name = "created", nullable = false, updatable=false)
    @Version
    private Date created;

    public Integer getId() {
        return id;
    }

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

    public User getUser() {
        return this.user;
    }

    public void setUser(User owner) {
        this.user = owner;
    }




    public String getStatus() {
        return status;
    }

    public void setStatus(String status) {
        this.status = status;
    }

    public Integer getOwnerid() {
        return ownerid;
    }

    public void setOwnerid(Integer ownerid) {
        this.ownerid = ownerid;
    }

    public Date getCreated() {
        return created;
    }

    public void setCreated(Date created) {
        this.created = created;
    }

    public Date getStartdate() {
        return startdate;
    }

    public void setStartdate(Date startdate) {
        this.startdate = startdate;
    }

    public Date getEnddate() {
        return enddate;
    }

    public void setEnddate(Date enddate) {
        this.enddate = enddate;
    }

}

Subscriber - User class

import java.util.Date;

import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.OneToOne;
import javax.persistence.PrimaryKeyJoinColumn;
import javax.persistence.Table;
import javax.persistence.Temporal;
import javax.persistence.TemporalType;


@Entity
@Table(name="users")
public class User {


    public User(){

    }

    @Id@GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name="userid")
    private Integer userid = 0;

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

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

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

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

    @Column(name = "type")
    private String userType;

    @OneToOne(fetch=FetchType.EAGER)
    @JoinColumn(name="cityid",insertable = false, updatable = false)
    private City city;

    private String cityid;


    @OneToOne(fetch=FetchType.EAGER)
    @JoinColumn(name="specialityid",insertable = false, updatable = false)
    private Speciality speciality;

    private Integer specialityid;


    @Column(name="medregno")
    private String regno;

    @Column(name="refcode")
    private String referalcode;

    public String getRegno() {
        return regno;
    }

    public void setRegno(String regno) {
        this.regno = regno;
    }

    public String getReferalcode() {
        return referalcode;
    }

    public void setReferalcode(String referalcode) {
        this.referalcode = referalcode;
    }

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

    @Column(name = "active")
    private boolean active;

    @Temporal(TemporalType.TIMESTAMP)
    @Column(name = "updated")
    private Date updated;

    @Temporal(TemporalType.TIMESTAMP)
    @Column(name = "created")
    private Date created;

    @Override
    public boolean equals(Object obj) {
        if (this == obj)
            return true;
        if (obj == null)
            return false;
        if (getClass() != obj.getClass())
            return false;
        User other = (User) obj;
        if (userid != other.userid)
            return false;
        return true;
    }

    public Integer getUserid() {
        return userid;
    }

    public void setUserid(Integer userid) {
        this.userid = userid;
    }

    public String getName() {
        return name;
    }

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

    public String getMobile() {
        return mobile;
    }

    public void setMobile(String mobile) {
        this.mobile = mobile;
    }

    public String getPassword() {
        return password;
    }

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

    public String getEmail() {
        return email;
    }

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

    public String getUserType() {
        return userType;
    }

    public void setUserType(String userType) {
        this.userType = userType;
    }


    public City getCity() {
        return city;
    }

    public void setCity(City city) {
        this.city = city;
    }

    public String getGender() {
        return gender;
    }

    public void setGender(String gender) {
        this.gender = gender;
    }


    public boolean isActive() {
        return active;
    }

    public void setActive(boolean active) {
        this.active = active;
    }

    public Date getCreated() {
        return created;
    }

    public void setCreated(Date created) {
        this.created = created;
    }

    public Date getUpdated() {
        return updated;
    }

    public void setUpdated(Date updated) {
        this.updated = updated;
    }

    public String getCityid() {
        return cityid;
    }

    public void setCityid(String cityid) {
        this.cityid = cityid;
    }

    public Speciality getSpeciality() {
        return speciality;
    }

    public void setSpeciality(Speciality speciality) {
        this.speciality = speciality;
    }

    public Integer getSpecialityid() {
        return specialityid;
    }

    public void setSpecialityid(Integer specialityid) {
        this.specialityid = specialityid;
    }


}

booking.getSlot() and booking.getSubscriber() returns null

Please let me know if i miss some configuration while mapping

EDIT1 Added code how the entity is getting loaded

public Booking addBooking(String title,String desc,int slotid,int subscriberid,Session session){
        Booking booking = new Booking();
        booking.setTitle(title);
        booking.setDesc(desc);
        booking.setSlotid(slotid);
        booking.setSubscriberid(subscriberid);
        booking.setCreated(new Date());
        Integer bookingid = (Integer) session.save(booking);
        session.flush();
        Booking bookingEntity = (Booking) session.createQuery("From Booking where id = ?").
                setParameter(0, bookingid).list().get(0);
        return bookingEntity;
    }

I am saving the entity and reloading it.

Answer 1

In your code :

booking.setSlotid(slotid);
booking.setSubscriberid(subscriberid);

You're just setting Integer values and not objects. Instead of this, try to set objects :

booking.setSlot(new Slot(slotid));
booking.setSubscriber(new Subscriber(subscriberid));

But as @Augusto said, the associations you're having in the session (Slot and Subscriber) are not full objects they contain only their ids. That's why you can't get other fields of these objects.

Answer 2

It's not working because Hibernate is retuning the same instance it has already in its 1st level cache, which doesn't have a reference to any of the 2 other entities.

To fix this, you have to do a session.refresh(booking) rather than executing a query.