Updating values in an Embeddable class

Question

Here's what I'm trying to do...I have a Person

@Entity
@Table(name = "PERSON", 
   uniqueConstraints = {
       @UniqueConstraint(columnNames = {"SSN"})
   }
)
@DynamicInsert(true)
@DynamicUpdate(true)
@SelectBeforeUpdate(true)
public class Person implements java.io.Serializable {

    private static final long serialVersionUID = 6732775093033061190L;

    @Version
    @Column(name = "OBJ_VERSION")
    private Timestamp version;

    @Id
    @Column(name = "SSN", length = 12, nullable = false, insertable = true, updatable = true)
    private String ssn;

    @Column(name = "LAST_NAME", length = 50, nullable = false, insertable = true, updatable = true)
    private String lastName;

    @Column(name = "FIRST_NAME", length = 30, nullable = false, insertable = true, updatable = true)
    private String firstName;

    @Column(name = "MIDDLE_NAME", length = 30, nullable = true, insertable = true, updatable = true)
    private String middleName;

    @OneToOne(fetch = FetchType.LAZY, mappedBy = "person", cascade = CascadeType.ALL)
    private Passport passport;

    @OneToMany(fetch = FetchType.EAGER, mappedBy = "person", cascade = CascadeType.ALL, orphanRemoval = true)
    private Set<Citizenship> citizenship = new HashSet<>();

// Getters and setters left out for brevity

and each person can have one Passport

@Entity
@Table(name = "PASSPORT", 
   uniqueConstraints = {
       @UniqueConstraint(columnNames = {"SSN", "PASSPORT_NUMBER"})
   }
)
@DynamicInsert(true)
@DynamicUpdate(true)
@SelectBeforeUpdate(true)
public class Passport implements java.io.Serializable {

    private static final long serialVersionUID = 6732775093033061190L;

    @Version
    @Column(name = "OBJ_VERSION")
    private Timestamp version;

    @Id
    @Column(name = "SSN", length = 12, nullable = false, insertable = true, updatable = true)
    private String ssn;

    @OneToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "SSN")
    @MapsId
    private Person person;    

    @Column(name = "EXPIRATION_DATE", nullable = true, insertable = true, updatable = false)
    private GregorianCalendar expirationDate;

    @Column(name = "ISSUING_COUNTRY", nullable = true, insertable = true, updatable = false)
    private String issuingCountry;

    @Column(name = "PASSPORT_NUMBER", nullable = false, insertable = true, updatable = false)
    private String passportNumber;

// Getters and setters left out for brevity

This works, each person can have one Passport and the Passport.ssn is assigned the value of the Person.ssn. This is being done because SSN is a unique identifier and it avoids the need for link tables.

Each person can also have a Citizenship

@Entity
@Table(name = "CITIZENSHIP")
@DynamicInsert(true)
@DynamicUpdate(true)
@SelectBeforeUpdate(true)
public class Citizenship implements java.io.Serializable {

    private static final long serialVersionUID = 6732775093033061190L;

    @Version
    @Column(name = "OBJ_VERSION")
    private Timestamp version;   

    @EmbeddedId
    private CitizenshipId citizenshipId;

    @Column(name = "DATE_OF_CITIZENSHIP")
    private GregorianCalendar dateOfCitizenship;     

    @ManyToOne(fetch = FetchType.EAGER)
    @JoinColumn(name = "SSN")
    @MapsId("ssn")
    private Person person; 

// Getters and setters left out for brevity

I have successfully added a person with a passport and a person without a passport. I have added a third person with a passport and dual citizenship with

   // This person has a passport and is a dual citizen.
    person = new Person();
    person.setSsn("654-89-7531");
    person.setFirstName("Lois");
    person.setLastName("Lane");
    passport = new Passport();
    passport.setExpirationDate(new GregorianCalendar());
    passport.setIssuingCountry("USA");
    passport.setPassportNumber("987654");

    Set<Citizenship> citizenshipSet = new HashSet<>();

    CitizenshipId citizenshipId = new CitizenshipId();
    citizenshipId.setCountry("USA");

    Citizenship c = new Citizenship();
    c.setDateOfCitizenship(new GregorianCalendar());
    c.setCitizenshipId(citizenshipId);
    c.setPerson(person);
    citizenshipSet.add(c);

    citizenshipId = new CitizenshipId();
    citizenshipId.setCountry("CAN");
    c = new Citizenship();
    c.setDateOfCitizenship(new GregorianCalendar());
    c.setCitizenshipId(citizenshipId);   
    c.setPerson(person);
    citizenshipSet.add(c);

    person.setPassport(passport);
    passport.setPerson(person);

    session.saveOrUpdate(person);

    for(Citizenship citizen : citizenshipSet) {
        session.saveOrUpdate(citizen);            
    }
    session.flush();
    session.clear();

This looks weird/inefficient to me, but it does work (tips for improvement would be appreciated). But as desired, the Person.ssn is carried into the Citizenship. Here's the problem:

The Person with dual Citizenship currently has citizenship in USA and Canada. Let's assume this is wrong and the Person has citizenship in USA and Mexico, which means the CitizenshipId.country needs to change from "CAN" to "MEX". I have tried a bunch of variations of code like

        Criteria citCriteria = session.createCriteria(Citizenship.class);    
        citCriteria.add(Restrictions.eq("citizenshipId.ssn", "654-89-7531"));
        List<Citizenship> citizenship = citCriteria.list();

        for(Citizenship c : citizenship) {
            if("CAN".equalsIgnoreCase(c.getCitizenshipId().getCountry())) {
                session.evict(c);

                c.getCitizenshipId().setCountry("MEX");
                session.saveOrUpdate(c);
                session.flush();
                session.clear();
            }
        }

With "show_sql" on, this doesn't perform an update, even though I can see the values change when debugging. I did try an evict(), then set the country, then saveOrUpdate, which made a new entry (I figured it would).

Phew...the question is: How can the values in an Embeddable class be updated when that class is being used as an EmbeddedId? I feel like I'm close but just missing one thing...

Thanks.

Adding CitizenshipID for reference

@Embeddable
public class CitizenshipId implements Serializable {

    private static final long serialVersionUID = 6732775093033061190L;

    String ssn;
    String country;

// Omitted getters, setters, constructors, hashcode, and equals

Have you tried updating the `Person`, setting the citizenship property to the newly updated version? — Dan, Jul 31 '18 at 20:07
@Dan - I tried with and without the evict(). And yes, I tried updating the Person as well. No update. — BigFish, Jul 31 '18 at 20:13
Not yet...I put the update code into a try catch block and it's catching an unhandled exception "A different object with the same identifier value was already associated with the session". This indicates I may need to deep copy all objects associated with Citizenship...which seems stupid so I'm probably wrong... — BigFish, Aug 01 '18 at 14:05

score 0 · Answer 1 · answered Jul 31 '18 at 20:09

0

Have you tried:

if("CAN".equalsIgnoreCase(c.getCitizenshipId().getCountry())) {
                session.evict(c);

                c.getCitizenshipId().setCountry("MEX");
                c.getPerson().getCitizenship().add(c);  // TRY ADDING THIS
                session.saveOrUpdate(c);
                session.flush();
                session.clear();
}

answered Jul 31 '18 at 20:09

Dan

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As expected...this added a third citizenship rather than updating one. – BigFish Jul 31 '18 at 20:20

Dan · Answer 2 · 2018-07-31T20:46:50.933

0

if("CAN".equalsIgnoreCase(c.getCitizenshipId().getCountry())) {

                // TRY ADDING THIS ------------------------
                //session.evict(c);
                CitizenshipId cid = new CitizenshipId();
                cid.setSsn(c.getCitizenshipId().getSsn();
                cid.setCountry("MEX");
                c.setCitizenshipId(cid); // references new CID -- should issue update
                // ----------------------------------------- 
                session.saveOrUpdate(c);
                session.flush();
                session.clear();
}

I removed the .evict due to the description in the API:

Remove this instance from the session cache. Changes to the instance will not be synchronized with the database. This operation cascades to associated instances if the association is mapped with cascade="evict".

edited Jul 31 '18 at 20:46

answered Jul 31 '18 at 20:25

Dan

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I know this looks exactly like what you're doing, however Hibernate is a strange beast and I've found little things like this sometimes do work – Dan Jul 31 '18 at 20:29
This added a third citizenship rather than updating one. Yes, it can be a little quirky. – BigFish Jul 31 '18 at 20:32
What properties are encompassed in `CitizenshipId` ? – Dan Jul 31 '18 at 20:35
Whoops, I meant to comment out `session.evict(c)'` when I posted this code. – Dan Jul 31 '18 at 20:38
CitizenshipId added to OP. – BigFish Jul 31 '18 at 20:42
Running the updated answer doesn't issue an update, this is one of the two perplexing parts of this. – BigFish Jul 31 '18 at 20:44
Ok, last edit on this answer... I updated it to reference a new CitizenshipId. If this doesnt work, I'm stumped. – Dan Jul 31 '18 at 20:50

score 0 · Accepted Answer · answered Aug 01 '18 at 15:27

Topic How to update values associated with Primary Key in Spring-JPA is inline with what Dan posted above about creating a new object with the old object Id. However, topic Hibernate - update the primary key 'id' column in the table does state that Hibernate doesn't allow updates to primary keys.

The objective here was to create a Person with a(n) SSN, possibly with a Passport, and a Citizenship. SSN is intended to be the primary key so I mapped Person to Passport and Citizenship and used SSN as the JoinColumn.

Person to Passport is a one to one relationship, so that wasn't a problem.

Person to Citizenship is a one to many relationship. This relationship means I had to create an embeddable ID. To make each Citizenship unique the embeddable class CitizenshipId was created with SSN and Country.

Using the accepted answer for Hibernate - update the primary key 'id' column in the table I changed the variations of

    Criteria citCriteria = session.createCriteria(Citizenship.class);    
    citCriteria.add(Restrictions.eq("citizenshipId.ssn", "654-89-7531"));
    List<Citizenship> citizenship = citCriteria.list();

    for(Citizenship c : citizenship) {
        if("CAN".equalsIgnoreCase(c.getCitizenshipId().getCountry())) {
            session.evict(c);

            c.getCitizenshipId().setCountry("MEX");
            session.saveOrUpdate(c);
            session.flush();
            session.clear();
        }
    }

to

Query query=session.createQuery("update Citizenship set country = :country1 where ssn = :ssn and country = :country2")
    .setString("country1", "MEX").setString("ssn", "654-89-7531").setString("country2", "CAN");
query.executeUpdate();

And an update did occur. Being unable to make an update via typical code (use criteria to get data, update it, then call saveOrUpdate) but being able to make an update via a query doesn't make a whole lot of sense to me. I know that key management is more times than not best left to the database, but when a unique value such as SSN is being used there is no need for another key. If an ID is identified within the code without a generation strategy it stands to reason that the IDs can be updated...JMHO.

Thanks to Dan for his ideas. I hope this topic and its references helps others.

Updating values in an Embeddable class

3 Answers3