I want to copy the entity's UUID, generated at run time to another field.
The entity id is generated via the code described bellow:
package eclipselink.example;
public class UUIDSequence extends Sequence implements SessionCustomizer {
public UUIDSequence() {
super();
}
public UUIDSequence(String name) {
super(name);
}
#Override
public Object getGeneratedValue(Accessor accessor,
AbstractSession writeSession, String seqName) {
return UUID.randomUUID().toString().toUpperCase();
}
...
public void customize(Session session) throws Exception {
UUIDSequence sequence = new UUIDSequence("system-uuid");
session.getLogin().addSequence(sequence);
}
}
Persitence.xml:
property name="eclipselink.session.customizer" value="eclipselink.example.UUIDSequence"
The entity:
public abstract class MyEntity{
private String id;
private String idCopy;
#Id
#Basic(optional = false)
#GeneratedValue(generator="system-uuid")
#XmlElement(name = "ID")
public String getId() {
return id;
}
}
How can I instruct JPA (Eclipse-link) to copy the UUID generated at runtime to idCopy field as well?
I'm not 100% sure this will work (I don't know if EclipseLink calls the setter or assigns the field directly), but give this a try:
public abstract class MyEntity{
private String id;
private String idCopy;
#Id
#Basic(optional = false)
#GeneratedValue(generator="system-uuid")
#XmlElement(name = "ID")
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
this.idCopy = id;
// or
// this.setIdCopy(id);
}
}
Related
i'm new to Springboot. I'm trying to implement a simple REST api using :
-Springboot, JPA & rest along with hibernate
I have a 2 tables database, Notebook that contains 1 to many notes
I already setup the 2 tables and relationships. I also created a NotebookRepository and NoteRepository to get basic CRUD operations via the springboot rest. The Database connection and relationships are functionning
but i don't know how to add a new note (it has a notebook_id foreign key which msut NOT be NULL) and everytime i tryto post something along these lines
{
"title:"abc",
"text":"whatever",
"notebook":{
"id":2
}
}
i get this error :
Caused by: java.sql.SQLIntegrityConstraintViolationException: Column 'notebook_id' cannot be null
#Entity
#Table(name="notebook")
public class NoteBook {
#Id
#GeneratedValue(strategy=GenerationType.IDENTITY)
#Column(name="id")
private int id;
#Column(name="name")
private String name;
#OneToMany(mappedBy="notebook", cascade=CascadeType.ALL)
List<Note> notes;
public NoteBook() {
}
public NoteBook(String name) {
this.name = name;
}
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 List<Note> getNotes() {
return notes;
}
public void setNotes(List<Note> notes) {
this.notes = notes;
}
public void addNote(Note note) {
if(notes == null) {
notes = new ArrayList<>();
}
note.setNotebook(this);
notes.add(note);
}
#Entity
#Table(name="note")
public class Note {
#Id
#GeneratedValue(strategy=GenerationType.IDENTITY)
#Column(name="id")
private int id;
#Column(name="title")
private String title;
#Column(name="text")
private String text;
#ManyToOne(cascade={CascadeType.MERGE, CascadeType.DETACH, CascadeType.PERSIST, CascadeType.REFRESH})
#JoinColumn(name="notebook_id")
private NoteBook notebook;
public Note() {
}
public Note(String title, String text) {
this.title = title;
this.text = text;
}
#RepositoryRestResource(collectionResourceRel = "note", path = "notes")
public interface NoteRepository extends JpaRepository<Note, Integer>{
//No code...
}
#RepositoryRestResource(collectionResourceRel = "notebook", path = "notebooks")
public interface NotebookRepository extends JpaRepository<NoteBook, Integer>{
}
The problem is that the class Note doesn't have a constructor with NoteBook parameter to pass the created NoteBook object to, so the solution is to add this constructor:
public Note(String title, String text, NoteBook noteBook) {
this.title = title;
this.text = text;
this.noteBook = noteBook;
}
and it's enough to send the JSON object as you do, but just be aware of case-sensitivity:
{ "title:"abc", "text":"whatever", "noteBook":{ "id":2 } }
I think you need to add referencedColumnName = "id" for JoinColumn annotation for notebook field in Note class.
Maybe you have problem with IDENTITY generation type. See this problem with null pointer
I am stuck with this error message, that appears every time I want to add a ManytoOne relationship with another entity class.
The class must use a consistent access type (either field or property). There is no ID defined for this entity hierarchy
This is my entity Transaction
#Entity
#Table(name = "CustomerTransaction")
public class CustomerTransaction implements Serializable {//this is the line with the error message
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
#ManyToOne //This generates the problem
#JoinColumns({
#JoinColumn(name = "CUS_ID", referencedColumnName = "IDCUSTOMER") })
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
private long transactionID;
#Temporal(TemporalType.TIMESTAMP)
private Date buyDate;
public Date getBuyDate() {
return buyDate;
}
public void setBuyDate(Date buyDate) {
this.buyDate = buyDate;
}
public long getTransactionID() {
return transactionID;
}
public void setTransactionID(long transactionID) {
this.transactionID = transactionID;
}
public String getCarYear() {
return carYear;
}
public void setCarYear(String carYear) {
this.carYear = carYear;
}
public Date getTransactionDate() {
return transactionDate;
}
public void setTransactionDate(Date transactionDate) {
this.transactionDate = transactionDate;
}
private String carYear;
#Temporal(TemporalType.TIMESTAMP)
private Date transactionDate;
JPA annotation should all be placed either on fields or on accessor methods. You've placed the #Id and #GeneratedValue annotation on a field (private Long id), but #ManyToOne and #JoinColumns on a getter (public Long getId()). Move the latter on a field as well.
i had similar error but in the end, i realized #Id was referencing this package org.springframework.data.annotation.Id instead of javax.persistence.Id. i was using #MappedSuperClass approach so as soon as i corrected this, everything worked fine
You need to import #Id from "import javax.persistence.Id;"
How can I implement a bidirectional one-to-one mapping using Google Application Engine (GAE) using Java Data Objects (JDO)?
I have a User class which holds contactInfo object and a ContactInfo class that holds a user object
#PersistenceCapable(identityType ="APPLICATION", detachable = "true")
public class User{
#PrimaryKey
#Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
private Long id;
private String name;
#Persistent(dependent = "true")
private ContactInfo child;
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public ContactInfo getChild() {
return child;
}
public void setChild(ContactInfo child) {
this.child = child;
}
}
#PersistenceCapable(identityType ="APPLICATION", detachable = "true")
public class ContactInfo {
#PrimaryKey
#Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
private Key id;
#Persistent(mappedBy = "child")
private User parent;
private String contactDetail;
public Key getId() {
return id;
}
public void setId(Key id) {
this.id = id;
}
public String getContactDetail() {
return contactDetail;
}
public void setContactDetail(String contactDetail) {
this.contactDetail = contactDetail;
}
}
Following error i am getting while testing API from API explorer
com.google.appengine.repackaged.org.codehaus.jackson.map.JsonMappingException: Infinite recursion (StackOverflowError) (through reference chain: com.demo.jdo.ContactInfo[\"user\"]->com.demo.jdo.User[\"contactInfo\"]->com.demo.jdo.ContactInfo[\"user\"]-
Standard JDO 1-1 bidir is simply found from http://www.datanucleus.org/products/accessplatform_3_1/jdo/orm/one_to_one.html#bi
GAE ought to be no different in this respect; last time I used it (maybe 3 yrs ago) they had some tests, think those under here http://code.google.com/p/datanucleus-appengine/source/browse/#svn%2Ftrunk%2Ftests%2Fcom%2Fgoogle%2Fappengine%2Fdatanucleus
Your question provides no definition of what you have tried in terms of annotations
Got the Solution, problem was with wrong use of mappedBy & presence of getter and setter of parent object in child.
#Persistent(mappedBy = "") annotation should only be at non-owner side
In on-owner/ child side there should not be any getter/setter present for owner/parent object.
Working code:
User.java
import javax.jdo.annotations.IdGeneratorStrategy;
import javax.jdo.annotations.IdentityType;
import javax.jdo.annotations.PersistenceCapable;
import javax.jdo.annotations.Persistent;
import javax.jdo.annotations.PrimaryKey;
#PersistenceCapable(identityType = IdentityType.APPLICATION, detachable = "true")
public class User {
#PrimaryKey
#Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
private Long id;
private String name;
#Persistent(dependent = "true")
private ContactInfo contactInfo;
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public ContactInfo getContactInfo() {
return contactInfo;
}
public void setContactInfo(ContactInfo contactInfo) {
this.contactInfo = contactInfo;
}
}
ContactInfo.java
import javax.jdo.annotations.IdGeneratorStrategy;
import javax.jdo.annotations.IdentityType;
import javax.jdo.annotations.PersistenceCapable;
import javax.jdo.annotations.Persistent;
import javax.jdo.annotations.PrimaryKey;
import com.google.appengine.api.datastore.Key;
#PersistenceCapable(identityType = IdentityType.APPLICATION, detachable = "true")
public class ContactInfo {
#PrimaryKey
#Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
private Key id;
#Persistent(mappedBy = "contactInfo")
/*
* Important: Do not create getter and setters for this object else
* bidirectional mapping gives error
*/
private User user;
private String contactDetail;
public Key getId() {
return id;
}
public void setId(Key id) {
this.id = id;
}
public String getContactDetail() {
return contactDetail;
}
public void setContactDetail(String contactDetail) {
this.contactDetail = contactDetail;
}
}
I have a class hierarchy for JPA entities with the base class being a MappedSuperclass which has one ID defined. I am trying to use a composite key in a subclass however that does not seem to work
My code looks like this
#MappedSuperclass
public class BaseEntity implements Serializable {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Basic(optional = false)
#Column(name = "id")
protected Long id;
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
}
#Entity
#EntityListeners(EntityBaseListener.class)
#Inheritance(strategy=InheritanceType.JOINED)
#Table(name = "catalog_entity")
public class BaseCatalogEntity extends BaseEntity {
#Column(name = "created_at", nullable = false)
#Temporal(TemporalType.TIMESTAMP)
private Date createdAt;
#Column(name = "updated_at", nullable = false)
#Temporal(TemporalType.TIMESTAMP)
private Date updatedAt;
public void setCreatedAt(Date date)
{
createdAt = date;
}
public void setUpdatedAt(Date date)
{
updatedAt = date;
}
public Date getCreatedAt() {
return createdAt;
}
public Date getUpdatedAt() {
return updatedAt;
}
}
#Entity
#Table(schema = "student_catalog")
#IdClass(value = StudentCatalog.StudentCatalogPK.class)
public class StudentCatalog extends BaseCatalogEntity {
#Id
#Column(name = "name", nullable = false, length = 100)
private String name;
#Id
#Column(name = "version", nullable = false)
private Integer version;
#Column(name = "description" , length = 255)
private String description;
#Column(name = "vendor" , length = 50)
private String vendor;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Integer getVersion() {
return version;
}
public void setVersion(Integer version) {
this.version = version;
}
public String getDescription() {
return description;
}
public void setDescription(String description) {
this.description = description;
}
public String getVendor() {
return vendor;
}
public void setVendor(String vendor) {
this.vendor = vendor;
}
public static class StudentCatalogPK implements Serializable {
private Long id;
private String name;
private Integer version;
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Integer getVersion() {
return version;
}
public void setVersion(Integer version) {
this.version = version;
}
#Override
public boolean equals(Object obj) {
boolean result = false;
if(obj != null && (obj instanceof StudentCatalogPK)) {
StudentCatalogPK other = (StudentCatalogPK)obj;
result = (Objects.equals(this.id, other.id) && Objects.equals(this.name, other.name) &&
Objects.equals(this.version, other.version));
}
return result;
}
#Override
public int hashCode() {
return (27780 + (this.id != null ? this.id.hashCode() : 0) +
(this.version != null ? this.version.hashCode() : 0) +
(this.name != null ? this.name.hashCode() : 0));
}
}
}
I get the following exception:
Exception Description: Invalid composite primary key specification. The names of the primary key fields or properties in the primary key class [com.example.jpa.StudentCatalog$StudentCatalogPK] and those of the entity bean class [class com.example.jpa.StudentCatalog] must correspond and their types must be the same. Also, ensure that you have specified ID elements for the corresponding attributes in XML and/or an #Id on the corresponding fields or properties of the entity class.
I am using Eclipselink 2.5.1. Is there a way I can get this to work without changing the BaseEntity and BaseCatalogEntity classes?
It is not legal in JPA to redefine the id in subclasses. This would lead to ambiguities in the table mappings as well as in polymorphic queries.
The desire to extend the key defined in a superclass is a common issue when business keys are used for DB identity. I would advise to use only surrogate keys (like UUID) for DB identity and business keys for instance identity.
Under following conditions:
your base entity should use TABLE_PER_CLASS inheritance (and as I can see it is)
your base entity (composite key) key is of the same type as that one you want to have in your derived class (so there should be also composite key of String and Integer).
You can use #AttributeOverride annotation under class declaration, removing #Id fields from it:
#AttributeOverride(name = "id", column = #Column(name = "NAME"))
This - in result, can change column name in derived entity's table and that's the most you can acheive.
When using #MappedSuperClass, it would be advisable to make the BaseEntity Class as abstract and then extending the Base class from other Entity classes.
Cleaner approach keeping inheritance in mind and designing your application.
I have one exception, which yold what I have no mapping on table. But I have this
Exeption is : \
AnnotationException: mappedBy reference an unknown target entity property: Relative.people in Person.relations
Relative entity is here:
#Entity
#Table(name = "relation")
public class Relative extends AbstractModel<UUID> implements Model<UUID> {
private UUID id;
private Person person;
private RelationTypeEnum relation;
public Relative() {
}
#Override
public void assignId() {
id = UUID.randomUUID();
}
#Override
#Id
#Column(name = "id")
public UUID getId() {
return id;
}
#ManyToOne
#JoinColumn(name="person_id", nullable=false)
public Person getPerson() {
return person;
}
#Column(name = "relation")
public RelationTypeEnum getRelation() {
return relation;
}
public void setId(UUID id) {
this.id = id;
}
public void setPerson(Person person) {
this.person = person;
}
public void setRelation(RelationTypeEnum relation) {
this.relation = relation;
}
}
And Person entity is here:
#Entity
#Table(name = "people")
public class Person extends AbstractModel<UUID> implements Model<UUID> {
private UUID id;
private String name;
private List<Relative> relations;
#Override
public void assignId() {
id = UUID.randomUUID();
}
#Override
#Id
#Column(name = "id")
public UUID getId() {
return id;
}
#Column(name = "name")
public String getName() {
return name;
}
#OneToMany(targetEntity=Relative.class, cascade=CascadeType.ALL,
mappedBy="people")
public List<Relative> getRelations() {
return relations;
}
public void setId(UUID id) {
this.id = id;
}
public void setName(String username) {
this.name = username;
}
public void setRelations(List<Relative> relations) {
this.relations = relations;
}
}
Solved.
Just changed
#Table(name = "people")
to
#Table(name = "person")
In my case there was a project which included a copy of the jar causing this issue. It was a web project which is including the jar inside its lib i.e. 2 copies of the same jar one with a different class version. Only discovered this when I physically opened the main ear and found the 2nd jar inside a web project.