I have the below entities
#Entity
#Getter
#Setter
public class Aggregate {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
#OneToMany(mappedBy = "aggregate")
private Set<Single> singleSet;
}
#Entity
#Getter
#Setter
public class Single {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private String id;
private Integer number;
#ManyToOne
#JoinColumn(name = "agg_id")
private Aggregate aggregate;
}
I also have the below repository
public interface AggregateRepo extends CrudRepository<Aggregate, Long> {
}
I want to return all associated Single records where number in object Single is equal to some random number
I am assuming that the query will be something like this
public interface AggregateRepo extends CrudRepository<Aggregate, Long> {
public List<Single> findBySingleSet_Number(Integer number);
}
However when I try to use Intellij to complete my named query it always populates like this
public interface AggregateRepo extends CrudRepository<Aggregate, Long> {
public List<Single> findBySingleSet_Empty_Number(Integer number);
}
I am wondering what the Empty stands for ?
Also should I create another Single repository since the query is related to returning Single records.
Related
I have following object mapping in our project. One contact can have multiple quotes from typeA and typeB.
#Entity
#Table(name = "t_ind_contact")
public class Contact implements Serializable {
#Id
#Column(name = "id", unique = true)
private Long id;
#OneToMany
private List<Quote> quotes;
}
Abstract Quote class.
#Entity
#Inheritance
#DiscriminatorColumn(name = "app_code")
#Table(name = "t_ind_quote")
public abstract class Quote implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#Column(name = "id")
private long id;
#OneToMany
#JoinColumn(name = "contact_id")
private Contact contact;
#Column(name = "app_code", insertable = false, updatable = false)
private int appCode;
}
TypeA Quote class
#Entity
#DiscriminatorValue("1")
public class TypeAQuote implements Serializable {
private static final long serialVersionUID = 1L;
}
TypeB Quote class
#Entity
#DiscriminatorValue("2")
public class TypeBQuote implements Serializable {
private static final long serialVersionUID = 1L;
}
This mapping is working fine for all operations. But for some operations we need the contact object with typeA quotes only. As of now, we will filter typeA quotes after system loads data from the database.
Is there a way that we can populate a contact object only with typeA quotes? I mean even the generated queries will load only typeA quotes.
How can I extend an entity with another entity but both of them referring to the same table ? Is it possible ? The structure is something like this :
#Entity
#Table(name = "users")
#NamedQuery(name="User.findAll", query="SELECT u FROM User u")
public class User implements Serializable{
private int id;
private String name;
}
#Entity
#Table(name = "users")
#NamedQuery(name="SubUser.findAll", query="SELECT su FROM SubUser su")
public class SubUser extends User {
#Override
#Id
#GeneratedValue(strategy=GenerationType.AUTO)
public int getId() {
return super.getId();
}
//- Other fields and getter setter
}
I tried this way Extend JPA entity to add attributes and logic
but I got this exception
org.hibernate.mapping.SingleTableSubclass cannot be cast to org.hibernate.mapping.RootClass
Update 1
I already put the #Id for the SubUser because the #Entity shows this exception
The entity has no primary key attribute defined
Add the #Inheritance annotation to the super class
Implement Serializable
Add a getter for id (you don't need a setter necessarily)
id should be Integer, not int, so that you can represent unassigned ids with null.
Code:
#Entity
#Table(name = "users")
#Inheritance(strategy = InheritanceType.SINGLE_TABLE)
public class User implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#GeneratedValue(strategy=GenerationType.AUTO)
private Integer id;
private String name;
public Integer getId() {
return id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
#Entity
public class SubUser extends User {
}
Any basic JPA docs would describe inheritance, discriminators and use of #Id.
#Entity
#Inheritance(strategy=InheritanceType.SINGLE_TABLE)
#DiscriminatorColumn(name="DISCRIM", discriminatorType=DiscriminatorType.STRING)
#DiscriminatorValue("User")
#Table(name="users")
#NamedQuery(name="User.findAll", query="SELECT u FROM User u")
public class User implements Serializable{
#Id
#GeneratedValue(strategy=GenerationType.AUTO)
private int id;
private String name;
}
#Entity
#DiscriminatorValue("SubUser")
#NamedQuery(name="SubUser.findAll", query="SELECT su FROM SubUser su")
public class SubUser extends User {
}
I am trying to write a NamedQuery with multiple joins and one sub-Query.
These are my Entities (I have removed most of the columns so that Question doesn't get too long and reader wouldn't need to go through unnecessary columns)
#Entity
public class progressEntry implements Serializable {
#Id
#GeneratedValue
private int id;
}
#Entity
public class KnowledgeTransfer implements Serializable {
#Id
#GeneratedValue
private int id;
#ManyToOne
private progressEntry pEntry;
}
#Entity
public class ColleagueActivity implements Serializable {
#Id
#GeneratedValue
private int id;
#ManyToOne
private KnowledgeTransfer knowledgeTransfer;
#ManyToOne
private College college;
}
#Entity
public class College implements Serializable {
#Id
#GeneratedValue
private Integer id;
private Integer studentNumber;
}
When I wrote the Native Query for this one, it works fine but I was wanted to learn how to write a Named Query with this one.
Here is what I tried which throws an Exception:
select progressEntry p where p.id in (select kt.progressEntryId from KnowledgeTransfer kt join ColleagueActivity cc on cc.ktid=kt.id join College c on c.id=cc.colleagueId where c.student.studentNumber= :studentNumber)
Please let me know if there is any more information that you would like me to post.
Thanks in advance.
I am using Hibernate-search for searching data in my Jboss application. I have 3 JPA entity classes that all extend BaseEntity class and each are indexed by Lucene. For example:
#MappedSuperclass
public abstract class BaseEntity implements Serializable {
#Temporal(TemporalType.TIMESTAMP)
private Date created;
public abstract Long getId();
}
#Entity
#Table(name = "DVD")
public class Dvd extends BaseEntity {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
#Field
private String title;
}
#Entity
#Table(name = "BOOK")
public class Book extends BaseEntity {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
#Field
private String author;
}
Now I would like to search for either DVD title or Book author by wildcard search query and get the result list as List. This is what I have this far:
public List<BaseEntity> search(String query, int firstResult, int maxResults) {
List<BaseEntity> results = null;
FullTextEntityManager fullTextEntityManager = Search.getFullTextEntityManager(em);
Query luceneQuery = new WildcardQuery(new Term("*", "*" + query + "*"));
FullTextQuery fullTextQuery = fullTextEntityManager.createFullTextQuery(luceneQuery, BaseEntity.class);
fullTextQuery.setFirstResult(firstResult);
fullTextQuery.setMaxResults(maxResults);
results = fullTextQuery.getResultList();
return results;
}
But with this I am not getting any results. How is it possible to get this to work or is there even way without using buildQueryBuilder for each entity? Thanks!
You'll want to use the varargs-style method for the classes, like so:
FullTextQuery fullTextQuery = fullTextEntityManager.createFullTextQuery(luceneQuery, DVD.class, Book.class);
This is because when Hibernate Search creates the search query, it adds the class name(s) to the query (for the _hibernate_class field, which is the indexed class' name).
I have two or more tables resembles each other.
PARENT
ID | PK
NAME | VARCHAR
CHILD
ID |PK
NAME | VARCHAR
AGE | INT
It's not #Inheritance situation because they are independent entities and related to each other by #OneToMany or #ManyToOne.
I create entity class for each other.
#Entity
public class Parent {
#Id
private Long id;
private String name;
#ManyToOne(mappedBy = "parent")
private Collection<Child> children;
}
#Entity
public class Child {
#Id
private Long id;
private String name;
private int age;
#OneToMany
private Parent parent;
}
Is there any nice way to share common fields mappings?
// #MappedSuperclass // is this what it is exactly for?
public abstract class Base {
// #Id protected Long id; // ##?
#Column(name = "name", nullable = false)
private String name;
}
#Entity
public class Parent extends Base {
#Id
#TableGenerator(...)
#GeneratedValue(...)
protected Long id;
#ManyToOne(mappedBy = "parent")
private Collection<Child> children;
}
#Entity
public class Child extends Base {
#Id
#TableGenerator(...)
#GeneratedValue(...)
protected Long id;
private int age;
#OneToMany
private Parent parent;
}
Is this OK?
Is it even possible declaring #Id protected Long id; on the Base leaving #TableGenerator and #GeneratedVAlue on extended classes?
Is there any nice way to share common fields mappings?
MappedSuperclass is exactly right tool for that.
Is it even possible declaring #Id protected Long id; on the Base
leaving #TableGenerator and #GeneratedVAlue on extended classes?
No, it is not possible.