many to one relationship between composite keys - java

I am building a spring mvc application with hibernate, and JPA that needs to model a few underlying MYSQL data tables that each have composite keys with the same two data types, so each table has its own composite key class, even though all the composite keys are based on the same two data types with exact same property names. I am getting a hibernate mapping error when I try to compile the app, and I am wondering if this might be because hibernate might not be able to equate the different primary key classes. Can someone show me how to fix this so that my app will compile?
Here is the part of my Description class that establishes the ManyToOne relationship between Description and Concept classes based on their corresponding composite primary key classes:
#ManyToOne
#JoinColumn(name="descriptionPK", referencedColumnName = "conceptPK")
private Concept concept;
Here is the error that I am getting:
Caused by: org.hibernate.MappingException:
Unable to find column with logical name:
conceptPK in org.hibernate.mapping.Table(sct2_concept) and its related supertables and secondary tables
The code for ConceptPK is:
#Embeddable
class ConceptPK implements Serializable {
#Column(name="id", nullable=false)
protected BigInteger id;
#Column(name="effectiveTime", nullable=false)
#Type(type="org.jadira.usertype.dateandtime.joda.PersistentDateTime")
private DateTime effectiveTime;
public ConceptPK() {}
public ConceptPK(BigInteger bint, DateTime dt) {
this.id = bint;
this.effectiveTime = dt;
}
/** getters and setters **/
public DateTime getEffectiveTime(){return effectiveTime;}
public void setEffectiveTime(DateTime ad){effectiveTime=ad;}
public void setId(BigInteger id) {this.id = id;}
public BigInteger getId() {return id;}
#Override
public boolean equals(Object obj) {
if (this == obj) return true;
if (obj == null) return false;
if (getClass() != obj.getClass()) return false;
final ConceptPK other = (ConceptPK) obj;
if (effectiveTime == null) {
if (other.effectiveTime != null) return false;
} else if (!effectiveTime.equals(other.effectiveTime)) return false;
if (id == null) {
if (other.id != null) return false;
} else if (!id.equals(other.id)) return false;
return true;
}
#Override
public int hashCode() {
int hash = 3;
hash = 53 * hash + ((effectiveTime == null) ? 0 : effectiveTime.hashCode());
hash = 53 * hash + ((id == null) ? 0 : id.hashCode());
return hash;
}
}
The code for DescriptionPK is:
#Embeddable
class DescriptionPK implements Serializable {
#Column(name="id", nullable=false)
protected BigInteger id;
#Column(name="effectiveTime", nullable=false)
#Type(type="org.jadira.usertype.dateandtime.joda.PersistentDateTime")
private DateTime effectiveTime;
public DescriptionPK() {}
public DescriptionPK(BigInteger bint, DateTime dt) {
this.id = bint;
this.effectiveTime = dt;
}
/** getters and setters **/
public DateTime getEffectiveTime(){return effectiveTime;}
public void setEffectiveTime(DateTime ad){effectiveTime=ad;}
public void setId(BigInteger id) {this.id = id;}
public BigInteger getId() {return id;}
#Override
public boolean equals(Object obj) {
if (this == obj) return true;
if (obj == null) return false;
if (getClass() != obj.getClass()) return false;
final DescriptionPK other = (DescriptionPK) obj;
if (effectiveTime == null) {
if (other.effectiveTime != null) return false;
} else if (!effectiveTime.equals(other.effectiveTime)) return false;
if (id == null) {
if (other.id != null) return false;
} else if (!id.equals(other.id)) return false;
return true;
}
#Override
public int hashCode() {
int hash = 3;
hash = 53 * hash + ((effectiveTime == null) ? 0 : effectiveTime.hashCode());
hash = 53 * hash + ((id == null) ? 0 : id.hashCode());
return hash;
}
}

You need to change #ManyToOne annotation to use multiple columns as shown below, and also you dont need to create duplicate two embeddable classes ConceptPK and DescriptionPK if all properties are same, just create one EmbeddablePK and use in both entities.
#OneToMany(mappedBy = "concept", cascade = CascadeType.ALL, fetch = FetchType.EAGER)
public List<Description> descriptions = new LinkedList<Description>();
And Description class:
#ManyToOne
#JoinColumns({ #JoinColumn(name = "A_COLUMN", referencedColumnName = "A_COLUMN", insertable = false, updatable = false),
#JoinColumn(name = "B_COLUMN", referencedColumnName = "B_COLUMN", insertable = false, updatable = false),
})
public Concept concept;

Related

JPA stackoverflow error when fetching data

I have 2 entities namely Teacher and Club, I need to retrieve the teacher data along with its related club and/or sports.
I a bit new to JPA so am having trouble debugging the stack overflow error I get when I use the findAll method on the Teacher repository.
I had tried adding #JsonIgnore annotation to my one-to-many annotation to deal with the recursion problem as suggested in some similar questions but was still getting problems and am not sure how exactly it's supposed to solve the problem.
TEACHER ENTITY:
#Entity
#Table(name = "TEACHER")
public class Teacher {
private String id;
private String name;
private Collection<ClubTeacher> clubTeachersById;
#Id
#Column(name = "Id", nullable = false, length = 10)
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
#Basic
#Column(name = "NAME", nullable = true, length = 25)
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
#Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
Teacher teacher = (Teacher) o;
if (id != null ? !id.equals(teacher.id) : teacher.id != null) return false;
if (name != null ? !name.equals(teacher.name) : teacher.name != null) return false;
return true;
}
#Override
public int hashCode() {
int result = id != null ? id.hashCode() : 0;
result = 31 * result + (name != null ? name.hashCode() : 0);
return result;
}
#OneToMany(mappedBy = "TICClub" ,fetch = FetchType.EAGER)
public Collection<ClubTeacher> getClubTeachersById() {
return clubTeachersById;
}
public void setClubTeachersById(Collection<ClubTeacher> clubTeachersById) {
this.clubTeachersById = clubTeachersById;
}
}
CLUB ENTITY:
#Entity
#Table(name = "CLUB_TEACHER", schema = "abbc", catalog = "")
#IdClass(ClubTeacherPK.class)
public class ClubTeacher implements Serializable {
private String tic;
private String clubkey;
private Teacher teacherByTic;
#Id
#Column(name = "TIC", nullable = false, length = 10)
public String getTic() {
return tic;
}
public void setTic(String tic) {
this.tic = tic;
}
#Id
#Column(name = "CLUBKEY", nullable = false, length = 25)
public String getClubkey() {
return clubkey;
}
public void setClubkey(String clubkey) {
this.clubkey = clubkey;
}
#Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
ClubTeacher that = (ClubTeacher) o;
if (tic != null ? !tic.equals(that.tic) : that.tic != null) return false;
if (clubkey != null ? !clubkey.equals(that.clubkey) : that.clubkey != null) return false;
return true;
}
#Override
public int hashCode() {
int result = tic != null ? tic.hashCode() : 0;
result = 31 * result + (clubkey != null ? clubkey.hashCode() : 0);
return result;
}
#ManyToOne
#JoinColumn(name = "TIC", referencedColumnName = "Id", nullable = false,insertable=false, updatable=false)
public Teacher getTeacherByTic() {
return teacherByTic;
}
public void setTeacherByTic(Teacher teacherByTic) {
this.teacherByTic = teacherByTic;
}
}
STACK TRACE:
2021-02-17 21:42:56.516 ERROR 20546 --- [nio-3005-exec-2] o.a.c.c.C.[.[.[/].[dispatcherServlet] : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Handler dispatch failed; nested exception is java.lang.StackOverflowError] with root cause
java.lang.StackOverflowError: null
at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$Adapter.write(ReflectiveTypeAdapterFactory.java:245) ~[gson-2.8.6.jar:na]
at com.google.gson.Gson$FutureTypeAdapter.write(Gson.java:1027) ~[gson-2.8.6.jar:na]
at com.google.gson.internal.bind.TypeAdapterRuntimeTypeWrapper.write(TypeAdapterRuntimeTypeWrapper.java:69) ~[gson-2.8.6.jar:na]
at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$1.write(ReflectiveTypeAdapterFactory.java:127) ~[gson-2.8.6.jar:na]
at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$Adapter.write(ReflectiveTypeAdapterFactory.java:245) ~[gson-2.8.6.jar:na]
at com.google.gson.internal.bind.TypeAdapterRuntimeTypeWrapper.write(TypeAdapterRuntimeTypeWrapper.java:69) ~[gson-2.8.6.jar:na]
at com.google.gson.internal.bind.CollectionTypeAdapterFactory$Adapter.write(CollectionTypeAdapterFactory.java:97) ~[gson-2.8.6.jar:na]
at com.google.gson.internal.bind.CollectionTypeAdapterFactory$Adapter.write(CollectionTypeAdapterFactory.java:61) ~[gson-2.8.6.jar:na]
....

Updating a ManyToMany relationship to include a new field

So, I've got an existing ManyToMany relationship set up in my spring application. It appears that I made a mistake by setting this up using the #ManyToMany annotation, because now I need to add a field to the join table, and this does not appear to be an easy feat.
My structure is shipments and products. The shipment table stores information about who the shipment was sent to, what date it was sent, etc. The product table stores information about the product, who makes it, description, size, etc.
What I failed to consider when building this out was, I will need to track quantity of product shipped when I create a shipment, which should be done on the join table.
I've been working along with this example: https://vladmihalcea.com/the-best-way-to-map-a-many-to-many-association-with-extra-columns-when-using-jpa-and-hibernate/
UPDATE:
I've been working through the example above and have run into an issue with infinite recursive calls between the product and shipment tables. My structure is as follows:
ShipmentProductID.java:
// Package and Imports here
#Embeddable
public class ShipmentProductId
implements Serializable {
#Column(name = "product_id")
private Long productId;
#Column(name = "shipment_id")
private Long shipmentId;
private ShipmentProductId() {}
public ShipmentProductId(
Long productId,
Long shipmentId) {
this.productId = productId;
this.shipmentId = shipmentId;
}
// Getters and Setters here
#Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass())
return false;
ShipmentProductId that = (ShipmentProductId) o;
return Objects.equals(productId, that.productId) &&
Objects.equals(shipmentId, that.shipmentId);
}
#Override
public int hashCode() {
return Objects.hash(productId, shipmentId);
}
}
ShipmentProduct.java:
// Package and Imports here
#Entity(name = "ShipmentProduct")
#Table(name = "shipment_product")
public class ShipmentProduct {
#EmbeddedId
private ShipmentProductId id;
#ManyToOne(fetch = FetchType.LAZY)
#MapsId("productId")
private Product product;
#ManyToOne(fetch = FetchType.LAZY)
#MapsId("shipmentId")
private Shipment shipment;
#Column(name = "created_on")
private Date createdOn = new Date();
private ShipmentProduct() {}
public ShipmentProduct(Product product, Shipment shipment) {
this.product = product;
this.shipment = shipment;
this.id = new ShipmentProductId(product.getId(),
shipment.getId());
}
// Getters and Setters here
#Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass())
return false;
ShipmentProduct that = (ShipmentProduct) o;
return Objects.equals(product, that.product) &&
Objects.equals(shipment, that.shipment);
}
#Override
public int hashCode() {
return Objects.hash(product, shipment);
}
}
Product.java:
// Package and Imports here
#Entity
#Data
#Cache( usage = CacheConcurrencyStrategy.READ_WRITE )
public class Product extends AbstractEntity {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "id")
private Long id;
#JsonIgnoreProperties("products")
// Have tried #JsonIgnore as well
#OneToMany(
mappedBy = "product",
orphanRemoval = true
)
private List<ShipmentProduct> shipments = new ArrayList<>();
#NotNull
private Integer quantity;
public boolean isAssociated(Client client){
if( this.client == null || this.client.getId() == null ||
client == null || client.getId() == null ) return
false;
return this.client.getId() == client.getId();
}
public boolean isAssociated(Expression expression){
if( this.expression == null || this.expression.getId() == null
||
expression == null || expression.getId() == null )
return false;
return this.expression.getId() == expression.getId();
}
public void addShipment(Shipment shipment) {
ShipmentProduct shipmentProduct = new ShipmentProduct(this,
shipment);
shipments.add(shipmentProduct);
shipment.getProducts().add(shipmentProduct);
}
public Set<Shipment> getAllShipments(){
Set<Shipment> shipmentList = new HashSet<>();
for (ShipmentProduct shipmentProduct : shipments) {
shipmentList.add(shipmentProduct.getShipment());
}
return shipmentList;
}
#Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
Product product = (Product) o;
return Objects.equals(id, product.id);
}
#Override
public String toString(){
return "";
}
#Override
public int hashCode() {
return Objects.hash(id);
}
}
Shipment.java:
// Package and Imports here
#Entity
#Data
#ToString(exclude = {"products", "contacts"})
#EqualsAndHashCode(exclude = {"products", "contacts"})
public class Shipment extends AbstractEntity {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#JsonIgnoreProperties("shipments")
#OneToMany(
mappedBy = "shipment",
orphanRemoval = true
)
private List<ShipmentProduct> products = new ArrayList<>();
public Set<Product> getAllProducts(){
Set<Product> productList = new HashSet<>();
for (ShipmentProduct shipmentProduct : products) {
productList.add(shipmentProduct.getProduct());
}
return productList;
}
public void addProduct(Product product) {
ShipmentProduct shipmentProduct = new ShipmentProduct(product,
this);
products.add(shipmentProduct);
product.getShipments().add(shipmentProduct);
}
public void removeProduct(Product product) {
for (Iterator<ShipmentProduct> iterator = products.iterator();
iterator.hasNext(); ) {
ShipmentProduct shipmentProduct = iterator.next();
if (shipmentProduct.getShipment().equals(this) &&
shipmentProduct.getProduct().equals(product)) {
iterator.remove();
shipmentProduct.getProduct().getShipments().remove(shipmentProduct);
shipmentProduct.setShipment(null);
shipmentProduct.setProduct(null);
}
}
}
public Optional<Product> getProductById(Long productId){
Optional<ShipmentProduct> shipmentProduct =
products.stream().filter(product ->
product.getId().equals(productId)).findFirst();
return productId == null ? Optional.empty() :
Optional.of(shipmentProduct.get().getProduct());
}
#Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
Shipment shipment = (Shipment) o;
return Objects.equals(id, shipment.id);
}
#Override
public String toString(){
return "";
}
#Override
public int hashCode() {
return Objects.hash(id);
}
}
It seems like I'm getting close, as this appears to be working aside from creating an infinitely large JSON object. I've tried all sorts of combinations of EAGER vs LAZY and JsonIgnore and JsonIgnoreProperties. Any thoughts on how to resolve this? My best guess is some interaction with Lombok, but I have not been able to figure this out.
Looks like I finally figured this out... I removed the following methods:
getAllProducts()
getAllShipments()
and replaced them with:
allProducts()
allShipments()
Having them as getters was always adding them to my return object, and they were not being cut off by #JsonIgnore, or anything else.
Next, I updated ShipmentProduct.java and added #JsonIgnore to both shipment and product, while removing #JsonIgnore and/or #JsonIgnoreProperties from Shipment.java and Product.java.
Then, in order to not receive errors when utilizing allProducts() or allShipments(), I added this to my application.properties file: spring.jackson.serialization.fail-on-empty-beans=false
Once this was all complete, I was also able to keep lombok.
Hopefully this helps somebody else in a similar situation. Also, if anybody has additional constructive criticism, please let me know!
You can keep #ManyToMany annotation, just add the joining table in your db and map it:
#JoinTable(
name = "joining_table",
joinColumns = #JoinColumn(
name = "this_id_in_jt",
referencedColumnName = "this_id"
),
inverseJoinColumns = #JoinColumn(
name = "other_id_in_jt",
referencedColumnName = "other_id"
)
)
#ManyToMany
private List<Other> others;

Transaction is getting rolledback while persisting objects in hibernate

I have following code to persist data in Oracle.
Language lang = new Language();
lang.setLangCode("06");
lang.setLanguage("german");
Data dc = new Data();
dc.setDescription("description_german");
dc.setName("name_german");
dc.setLanguage(lang);
//2.
Language lang2 = new Language();
lang2.setLangCode("06");
lang2.setLanguage("german");
Document doc = new Document();
doc.setDescription("description_de");
doc.setName("name_de");
doc.setLanguage(lang2); // When I do like: doc.setLanguage(lang) it persists the data
doc.setDataCollection(dc);
em.merge(doc);
When I run the above code it give me transaction rollback following are the logs
TRACE org.hibernate.engine.spi.ActionQueue.addResolvedEntityInsertAction - Adding resolved non-early insert action.
09-02-2018 15:14:54.273 TRACE org.hibernate.engine.internal.Cascade.cascade - Processing cascade ACTION_MERGE for: com.fis.cdpr.model.DataCollection
09-02-2018 15:14:54.273 TRACE org.hibernate.engine.internal.Cascade.cascade - Done processing cascade ACTION_MERGE for: com.fis.cdpr.model.DataCollection
09-02-2018 15:14:54.273 TRACE org.hibernate.engine.spi.CascadingAction.cascade - Cascading to merge: com.fis.cdpr.model.Language
09-02-2018 15:14:54.274 TRACE org.hibernate.event.internal.DefaultMergeEventListener.entityIsDetached - Merging detached instance
09-02-2018 15:14:54.274 TRACE org.hibernate.event.internal.DefaultLoadEventListener.proxyOrLoad - Loading entity: [com.fis.cdpr.model.Language#06]
09-02-2018 15:14:54.274 TRACE org.hibernate.event.internal.DefaultLoadEventListener.doLoad - Attempting to resolve: [com.fis.cdpr.model.Language#06]
09-02-2018 15:14:54.274 TRACE org.hibernate.event.internal.DefaultLoadEventListener.doLoad - Resolved object in session cache: [com.fis.cdpr.model.Language#06]
09-02-2018 15:14:54.274 DEBUG org.hibernate.jpa.spi.AbstractEntityManagerImpl.markForRollbackOnly - Mark transaction for rollback
I have overriden equals and hashcode for Language object
Then I tried following code just o check the problem and it worked!!
Language lang1 = new Language();
lang1.setLangCode("06");
Language lang2 = new Language();
lang2.setLangCode("06");
em.merge(lang1);
em.merge(lang2);
See logs below:
09-02-2018 16:59:44.840 TRACE org.hibernate.engine.spi.ActionQueue.addInsertAction - Adding insert with no non-nullable, transient entities: [EntityInsertAction[com.fis.cdpr.model.Language#06]]
09-02-2018 16:59:44.840 TRACE org.hibernate.engine.spi.ActionQueue.addResolvedEntityInsertAction - Adding resolved non-early insert action.
09-02-2018 16:59:44.842 TRACE org.hibernate.event.internal.DefaultMergeEventListener.entityIsDetached - Merging detached instance
09-02-2018 16:59:44.842 TRACE org.hibernate.event.internal.DefaultLoadEventListener.proxyOrLoad - Loading entity: [com.fis.cdpr.model.Language#06]
09-02-2018 16:59:44.843 TRACE org.hibernate.event.internal.DefaultLoadEventListener.doLoad - Attempting to resolve: [com.fis.cdpr.model.Language#06]
09-02-2018 16:59:44.843 TRACE org.hibernate.event.internal.DefaultLoadEventListener.doLoad - Resolved object in session cache: [com.fis.cdpr.model.Language#06]
09-02-2018 16:59:44.847 DEBUG org.hibernate.engine.transaction.internal.TransactionImpl.commit - committing
I need to understand why hibernate after looking Language object from cache is not able to persist same language object( diff reference ) but able to persist same object reference and also different language objects
I have provided relation on both Data and Document entites with Language as below
#ManyToOne(cascade= CascadeType.ALL)
#JoinColumn(name = "language_fk")
private Language language;
Update=> exception says
exception [java.lang.IllegalStateException: Multiple representations of the same entity [spring.model.Language#06] are being merged. Detached: [spring.model.Language#b588a401]; Detached: [spring.model.Language#b588a401]]
Document class
#Entity
public class Document {
#Id
#GeneratedValue(strategy=GenerationType.AUTO)
private int id;
#Column(name="doc_name", nullable=true)
private String name;
#ManyToOne(cascade=CascadeType.ALL)
#JoinColumn
private Language lang;
#ManyToOne(cascade=CascadeType.ALL)
#JoinColumn
private Data data;
public Data getData() {
return data;
}
public void setData(Data data) {
this.data = data;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Language getLang() {
return lang;
}
public void setLang(Language lang) {
this.lang = lang;
}
#Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + id;
result = prime * result + ((lang == null) ? 0 : lang.hashCode());
return result;
}
#Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (obj == null)
return false;
if (getClass() != obj.getClass())
return false;
Document other = (Document) obj;
if (id != other.id)
return false;
if (lang == null) {
if (other.lang != null)
return false;
} else if (!lang.equals(other.lang))
return false;
return true;
}
Data Class
#Entity
public class Data {
#Id
#GeneratedValue(strategy=GenerationType.AUTO)
private int id;
#Column(name="doc_name", nullable=true)
private String name;
#ManyToOne(cascade=CascadeType.ALL)
#JoinColumn(name="doc_fk")
private Document doc;
#ManyToOne(cascade=CascadeType.ALL)
#JoinColumn
private Language lang;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Document getDoc() {
return doc;
}
public void setDoc(Document doc) {
this.doc = doc;
}
public Language getLang() {
return lang;
}
public void setLang(Language lang) {
this.lang = lang;
}
#Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + id;
result = prime * result + ((lang == null) ? 0 : lang.hashCode());
return result;
}
#Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (obj == null)
return false;
if (getClass() != obj.getClass())
return false;
Data other = (Data) obj;
if (id != other.id)
return false;
if (lang == null) {
if (other.lang != null)
return false;
} else if (!lang.equals(other.lang))
return false;
return true;
}
}
}
Language class
#Entity
public class Language {
#Id
private String langCode;
private String language;
public String getLangCode() {
return langCode;
}
public void setLangCode(String langCode) {
this.langCode = langCode;
}
public String getLanguage() {
return language;
}
public void setLanguage(String language) {
this.language = language;
}
#Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + ((langCode == null) ? 0 : langCode.hashCode());
result = prime * result + ((language == null) ? 0 : language.hashCode());
return result;
}
#Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (obj == null)
return false;
if (getClass() != obj.getClass())
return false;
Language other = (Language) obj;
if (langCode == null) {
if (other.langCode != null)
return false;
} else if (!langCode.equals(other.langCode))
return false;
if (language == null) {
if (other.language != null)
return false;
} else if (!language.equals(other.language))
return false;
return true;
}
}
From the exception and when I executed em.merge(lang); em.merge(lang2) I believe it worked because there are two seperate calls to persist/merge the data thats why I never got exception while doing so. But otherwise it gives exception. Isn't hibernate suppose to merge objects when it finds one same object in Session. ?

Using Hibernate and TreeSet does not work the remove() and contains() methods

I want to have a sorted set by age;
The method compareTo() in this case works fine but the problem is that remove() and contians() methods returns always false;
INTERESTING: In case I uncomment the lines form compareTo() method, remove() and contains() methods works fine; but I want to use the other field as sorting.
Does someone have any idea why does not work properly; Found old Hibernate issue: https://hibernate.atlassian.net/browse/HHH-2634;
is this already fixed?
Bellow are the used classes:
#Entity(name = "CAMPAIGN")
public class Campaign implements Identifiable, Serializable {
public static final long serialVersionUID = 1L;
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "ID")
private Long id;
#OneToMany(mappedBy = "campaign", cascade = CascadeType.ALL, fetch = FetchType.EAGER, orphanRemoval = true)
#OrderBy("age ASC")
private SortedSet<MailingAddress> mailingAddresses = new TreeSet<>();
...
public void removeMailingAddress(MailingAddress mailingAddress) {
this.mailingAddresses.remove(mailingAddress);
//this.mailingAddresses.contains(mailingAddress);
mailingAddress.setCampaign(null);
}
}
And
#Entity(name = "MAILING_ADDRESS")
public class MailingAddress implements Identifiable, Comparable, Serializable {
public static final long serialVersionUID = 1L;
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "ID")
private Long id;
#ManyToOne
#JoinColumn(name = "CAMPAIGN_ID")
private Campaign campaign;
#Column(name = "AGE")
private Integer age;
#Override
public int compareTo(Object o) {
if (o == null) {
return 1;
}
if (!(o instanceof MailingAddress)) {
throw new ClassCastException("Cannot compare MailingAddress with " + o.getClass());
}
MailingAddress o1 = (MailingAddress) o;
int comparison;
// comparison for id
/*comparison = compareFields(this.id, o1.id);
if (comparison != 0) {
return comparison;
}*/
// comparison for ageBand
comparison = compareFields(this.age, o1.age);
if (comparison != 0) {
return comparison;
}
return 0;
}
private int compareFields(Comparable field1, Comparable field2) {
if (field1 == null && field2 == null) {
return 0;
} else if (field1 == null && field2 != null) {
return -1;
} else if (field1 != null && field2 == null) {
return 1;
}
return field1.compareTo(field2);
}
#Override
public boolean equals(Object o) {
return this.compareTo(o) == 0;
}
}
UPDATE:
Found that using SortedSet as interface for TreeSet in combination with Hibernate the methods remove() and contains() does not work properly.
"SortedSet mailingAddresses = new TreeSet<>();"
Changed the definition to "Set mailingAddresses = new TreeSet<>();" and the methods remove() and contains() works fine; Also the sorting that is using compareTo() is working also for other fields than id.
Probably there is a bug in combination of TreeSet, SortedSet and Hibernate. If someone found an explanation for this "bug" please let me know.
Here is a working version:
#Entity
public class MailingAddress implements Identifiable, Comparable, Serializable {
public static final long serialVersionUID = 1L;
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "ID")
private Long id;
private Integer age;
#Override
public int compareTo(Object o) {
if (o == null) {
return 1;
}
if (!(o instanceof MailingAddress)) {
throw new ClassCastException("Cannot compare MailingAddress with " + o.getClass());
}
MailingAddress o1 = (MailingAddress) o;
int comparison = compareFields(this.age, o1.age);
if (comparison != 0) {
return comparison;
}
return 0;
}
#Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
MailingAddress that = (MailingAddress) o;
if (id != null ? !id.equals(that.id) : that.id != null) return false;
return age != null ? age.equals(that.age) : that.age == null;
}
#Override
public int hashCode() {
return 31;
}
private int compareFields(Comparable field1, Comparable field2) {
if (field1 == null && field2 == null) {
return 0;
} else if (field1 == null && field2 != null) {
return -1;
} else if (field1 != null && field2 == null) {
return 1;
}
return field1.compareTo(field2);
}
}
AND
#Entity
public class Campaign implements Identifiable, Serializable {
public static final long serialVersionUID = 1L;
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "ID")
private Long id;
#OneToMany(mappedBy = "campaign", cascade = CascadeType.ALL, fetch = FetchType.EAGER, orphanRemoval = true)
#OrderBy("age ASC")
private Set<MailingAddress> mailingAddresses = new TreeSet<>();
...
}
The problem here is that you override equals without overriding hashCode.
Also, the reference check does not work for the merge entity state transition.
Since you don't have a natural business key in MailingAddress, you need to use the entity identifier like this:
#Override
public boolean equals(Object o) {
if (this == o) return true;
if (!(o instanceof MailingAddress)) return false;
MailingAddress ma = (MailingAddress) o;
return getId() != null && Objects.equals(getId(), ma.getId());
}
#Override
public int hashCode() {
return getClass().hashCode();
}
The getClass().hashCode() returns a constant value for allinstances, therefore allowing an entity that has a null id to be found in a HashSet even after the id is changed after calling persist on the transient entity.
But, that's not all.
Why do you use a TreeSet with #OrderBy("age ASC"). The order is given at query-time, and then you override that in Java. Since you use #OrderBy, it makes more sense to use a List since the sorting is done when executing the SELECT statement.

Column does not exist - Hibernate ManyToMany association class

I'm facing the following problem. Imagine this data model:
As you can see project_function entity is association many to many entity.
Here are my entity classes.
PeronalCard:
#Entity
#Table(name = "personal_card")
#XmlRootElement
public class PersonalCard implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Basic(optional = false)
#Column(name = "id_person")
private Integer idPerson;
/* SOME OTHER ATTRIBUTES */
#OneToMany(cascade = CascadeType.ALL, mappedBy = "projectFunctionPK.personalCard")
private Set<ProjectFunction> projectFunctionSet;
public PersonalCard() {
}
public Integer getIdPerson() {
return idPerson;
}
public void setIdPerson(Integer idPerson) {
this.idPerson = idPerson;
}
#XmlTransient
public Set<ProjectFunction> getProjectFunctionSet() {
return projectFunctionSet;
}
public void setProjectFunctionSet(Set<ProjectFunction> projectFunctionSet) {
this.projectFunctionSet = projectFunctionSet;
}
#Override
public int hashCode() {
int hash = 0;
hash += (idPerson != null ? idPerson.hashCode() : 0);
return hash;
}
#Override
public boolean equals(Object object) {
// TODO: Warning - this method won't work in the case the id fields are not set
if (!(object instanceof PersonalCard)) {
return false;
}
PersonalCard other = (PersonalCard) object;
if ((this.idPerson == null && other.idPerson != null) || (this.idPerson != null && !this.idPerson.equals(other.idPerson))) {
return false;
}
return true;
}
}
Project:
#Entity
#Table(name = "project")
#XmlRootElement
public class Project implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Basic(optional = false)
#Column(name = "id_project")
private Integer idProject;
/* OTHER ATTRIBUTES*/
#OneToMany(cascade = CascadeType.ALL, mappedBy = "projectFunctionPK.project")
private Set<ProjectFunction> projectFunctionSet;
public Project() {
}
public Integer getIdProject() {
return idProject;
}
public void setIdProject(Integer idProject) {
this.idProject = idProject;
}
#XmlTransient
public Set<ProjectFunction> getProjectFunctionSet() {
return projectFunctionSet;
}
public void setProjectFunctionSet(Set<ProjectFunction> projectFunctionSet) {
this.projectFunctionSet = projectFunctionSet;
}
#Override
public int hashCode() {
int hash = 0;
hash += (idProject != null ? idProject.hashCode() : 0);
return hash;
}
#Override
public boolean equals(Object object) {
// TODO: Warning - this method won't work in the case the id fields are not set
if (!(object instanceof Project)) {
return false;
}
Project other = (Project) object;
if ((this.idProject == null && other.idProject != null) || (this.idProject != null && !this.idProject.equals(other.idProject))) {
return false;
}
return true;
}
}
ProjectFunction:
#Entity
#Table(name = "project_function")
#XmlRootElement
#AssociationOverrides({
#AssociationOverride(name = "projectFunctionPK.project",
joinColumns = #JoinColumn(name = "id_project", referencedColumnName = "id_project")),
#AssociationOverride(name = "projectFunctionPK.personalCard",
joinColumns = #JoinColumn(name = "id_person", referencedColumnName = "id_person")) })
public class ProjectFunction implements Serializable {
private static final long serialVersionUID = 1L;
protected ProjectFunctionPK projectFunctionPK;
private Date fromd;
private Date tod;
public ProjectFunction() {
this.projectFunctionPK = new ProjectFunctionPK();
}
#EmbeddedId
public ProjectFunctionPK getProjectFunctionPK() {
return projectFunctionPK;
}
public void setProjectFunctionPK(ProjectFunctionPK projectFunctionPK) {
this.projectFunctionPK = projectFunctionPK;
}
#Column(name = "fromd")
#Temporal(TemporalType.DATE)
public Date getFromd() {
return fromd;
}
public void setFromd(Date fromd) {
this.fromd = fromd;
}
#Column(name = "tod")
#Temporal(TemporalType.DATE)
public Date getTod() {
return tod;
}
public void setTod(Date tod) {
this.tod = tod;
}
#Transient
public Project getProject() {
return projectFunctionPK.getProject();
}
public void setProject(Project project) {
this.projectFunctionPK.setProject(project);
}
#Transient
public PersonalCard getPersonalCard() {
return this.projectFunctionPK.getPersonalCard();
}
public void setPersonalCard(PersonalCard personalCard) {
//this.personalCard = personalCard;
this.projectFunctionPK.setPersonalCard(personalCard);
}
#Override
public int hashCode() {
int hash = 0;
hash += (projectFunctionPK != null ? projectFunctionPK.hashCode() : 0);
return hash;
}
#Override
public boolean equals(Object object) {
// TODO: Warning - this method won't work in the case the id fields are not set
if (!(object instanceof ProjectFunction)) {
return false;
}
ProjectFunction other = (ProjectFunction) object;
if ((this.projectFunctionPK == null && other.projectFunctionPK != null) || (this.projectFunctionPK != null && !this.projectFunctionPK.equals(other.projectFunctionPK))) {
return false;
}
return true;
}
}
And finally my embedded Primary Key ProjectFunctionPK:
#Embeddable
public class ProjectFunctionPK implements Serializable {
#ManyToOne
private Project project;
#ManyToOne
private PersonalCard personalCard;
public ProjectFunctionPK() {
}
public Project getProject() {
return project;
}
public void setProject(Project project) {
this.project = project;
}
public PersonalCard getPersonalCard() {
return personalCard;
}
public void setPersonalCard(PersonalCard personalCard) {
this.personalCard = personalCard;
}
#Override
public int hashCode() {
int hash = 3;
hash = 41 * hash + Objects.hashCode(this.project);
hash = 41 * hash + Objects.hashCode(this.personalCard);
return hash;
}
#Override
public boolean equals(Object obj) {
if (obj == null) {
return false;
}
if (getClass() != obj.getClass()) {
return false;
}
final ProjectFunctionPK other = (ProjectFunctionPK) obj;
if (!Objects.equals(this.project, other.project)) {
return false;
}
if (!Objects.equals(this.personalCard, other.personalCard)) {
return false;
}
return true;
}
}
First I save the Project. It works fine. Then i want to connect it using project_function - so I create project_function set them existing project and personal_card and after trying to persist I get following error:
Caused by: org.postgresql.util.PSQLException: ERROR: column projectfun0_.personalcard does not exist
Position: 8
at org.postgresql.core.v3.QueryExecutorImpl.receiveErrorResponse(QueryExecutorImpl.java:2198)
at org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:1927)
at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:255)
at org.postgresql.jdbc2.AbstractJdbc2Statement.execute(AbstractJdbc2Statement.java:561)
at org.postgresql.jdbc2.AbstractJdbc2Statement.executeWithFlags(AbstractJdbc2Statement.java:419)
at org.postgresql.jdbc2.AbstractJdbc2Statement.executeQuery(AbstractJdbc2Statement.java:304)
at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.extract(ResultSetReturnImpl.java:82)
... 119 more
So apparently Hibernate does not know projectfun0_.personalcard . But I dont know why. Do you see any error in the entity classes? Or could the error possibly be somewhere else ?
Thank you very much for all your answers :)
EmbeddedId documentation
Relationship mappings defined within an embedded id class are not supported.
So, ProjectFunctionPK should contain only basic mappings, and entity mappings should be done in the entity itself. Here are some related posts
https://stackoverflow.com/a/9760808/4074715
https://stackoverflow.com/a/4692144/4074715

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