I have an Entity "Person" which has following properties,
Id
Name
F-Name
Age
Address
When I call a repository function findAll() on Person, it returns a list of Persons.
List<Person> list = somefuntionToConvertIterableToList(personRepository.findAll());
this list has multiple objects of Person Type.
Person ...... Id1,Name1, F-Name1, Age1, Address1
Person .......IdN,NameN, F-NameN, AgeN, AddressN
I need to remove "Id" from all Persons, what should I do?
I know we can use "remove" to delete an element of list, but how to delete a property with in an element?
I think you need used : #JsonIgnore in Id look like:
#JsonIgnore
Field you want remove in reponse.
Or you can create DTO and put all field you want return look like :
public class PersonDTO {
//all field you want return
}
You can of course set id null or add ignores in serialization but maybe you do not want to load id at all. Usually you then would use DTO or Tuple to decide what fields to populate. So not first to populate all and then remove unneeded (I have not used your Person but just one simplified example class).
Tuple query in your repository would simply be like (JPQL):
#Query("SELECT te.name AS name, te.created as created FROM TestEntity te")
List<Tuple> findAllTuple();
This would need then do extra work to have tuple to correspond original entity when serialized. So preferably with a DTO, like:
// This class would be exactly as your Person but without that id
#AllArgsConstructor // you need the constructor for new in jpql
public class TestEntityDto {
private String name;
private LocalDateTime created;
}
while the query in your repository would be like:
#Query("SELECT NEW org.example.data.entity.dto.TestEntityDto(te.name, te.created) FROM TestEntity te")
List<TestEntityDto> findAllDto();
Related
I'm using spring-boot-starter-data-jdbc 2.4.2. In my domain aggregate I need to map a List of Strings that is populated from a column in another table. It is a legacy database so I have no control over the table and column names and need to use custom names. I see there is an #MappedCollection annotation, but can't see how to use it in this scenario. Below is my class:
#Data
#Table("NMT_MOVIE_THEATRE")
public class MovieTheatre {
#Id
#Column("MOVIE_THEATRE_ID")
private Long id;
#Column("ZIP_CODE")
private String zipCode;
// this comes from table NMT_CURRENT_MOVIE, column CM_ID, joined by MOVIE_THEATRE_ID
private List<String> currentMovieIds;
}
Using Spring Data JDBC, how can I create the one-to-many relation?
Wrap your String in a little entity.
#Table("NMT_CURRENTMOVIE")
class MovieId {
#Id
#Column("CM_ID")
final String id
// add constructor, equals and hashCode here or generate using Lombok
}
Then use it in the MovieTheatre. Since you don't have a column for an index, the proper collection to use is a Set
// ...
class MovieTheatre {
// ...
#MappedCollection(idColumn="MOVIE_THEATRE_ID")
Set<MovieId> currentMovieIds;
}
Note that equals and hashCode is important as well as the constructor taking all arguments used in those, since the entity is used in a Set.
I have a list of ids of a PanacheEntity. I want to find the list of PanacheEntities corresponding to these Id. Is there a built in or suggested API which can do this.
public class Person extends PanacheEntity {
public String name;
}
After a previous search, I have with me a list of ids of the Person entity. I would now like to get a list of the Person objects in a single DB query.
I tried Person.list("id", listOfIds), but this fails when there is more than one object in the list. Is there a better way than this
You should be able to do:
Person.list("id in ?1", listOfIds)
Lets say in my dao class i have a method annotated with sql: SELECT id, name, lat, long FROM table WHERE id = :id.
i want to map that to object like (pseudo):
public class Something {
public string Id;
public string Name;
public GeoLocation Location;
public Something(id, name, lat, long) {
this.Id = id;
this.Name = name;
this.Location = new GeoLocation(lat, long);
}
}
so, point is that i want to map flat select result into model with children made from some of the return fields.
Important is that i don’t want to have public get/set for all fields that sql returns.
I also want to avoid any room annotations on Something if possible (i am aware of solutions that involve #Embedded annotations).
In room the only possible way to convert fields into POJO that has no boiler point is indeed #Embedded annotation. Thats the best and simplest way to do it.
You can convert your sql query to your desired model with some other few methods which are not feasible.
Intermediate Model. That is convert your SQL result to a model that one to one matches to your fields. i.e.
public class PreSomething {
public string id;
public string name;
public long lat;
public long long;
}
After converting to PreSomething, you can have it get converted Something with any fashion you like.
Another way would be TypeConverters which changes database schema and will require you have database migration.
So, the only possible way is infact #Embedded. Now coming to your requirements,
Important is that i don’t want to have public get/set for all fields
that sql returns.
Every field that's stored in the database needs to be either public or have a "getter" method. Since your fields are all public you don't have to have any get/set for the fields.
I also want to avoid any room annotations on Something if possible (i
am aware of solutions that involve #Embedded annotations).
You have to annotate #Embedded the GeoLocation object (not Something) in order to be able to map your fields to a POJO.
One other thing to note that you SQLite, in that fashion Room, is case sensitive so. If you have to specify your fields with lowercase if your columns are lowercase. Otherwise you have to annotate them with #ColumnInfo and correct column name.
Let's say I have an entity
public class Person {
private String id;
private String firstname;
private String lastname;
private Set<Car> ownedCars;
}
Is there a way I can use query by example to find any person named James having both a Ferrari and Lamborghini?
If I use:
Person p = new Person();
p.setName("James");
p.getOwnedCars.addCar(new Car("Lamborgnihi"));
p.getOwnedCars.addCar(new Car("Ferrari"));
Example<Person> exampleOfPerson = Example.of(p);
List<Person> foundPersons = personRepository.finaAll(exampleOfPerson);
it seems it queries only on person's attributes and ignores any child collections.
You can use a query method for that. Let's say your Car has a property name that can be "Lamborghini" or "Ferrari"
interface PersonRepository extends JpaRepository<Person, String> {
List<Person> findByOwnedCarsNameIn(Collection<String> names);
}
Then you use it like this:
personRepository.findByOwnedCarsNameIn(Arrays.asList("Ferrari","Lamborghini"));
Some gotchas:
The method parameter can take any subclass of Collection, or an array.
The property names on Person and Car must match the method signature and the parameter name as shown above for spring to know how to generate the query, i.e. Person must have a property called "cars", and Car must have a property called "name".
I used JpaRepository, but this works with any of the Repository interfaces provided with spring data JPA
Does Spring Data have a mechanism for returning specific fields?
I'm familiar with the syntax:
Invoice findByCode(String code);
How about this:
Integer findIdByCode(String code);
which returns the id field only. Or
Tuple findIdAndNameByCode(String code);
which returns a tuple. Or
Invoice findIdAndNameByCode(String code);
which returns an entity only populated with specific fields. Can use a constructor taking only those field if defined - else construct empty and populate the fields.
EDIT
To qualify some more, I'm aware of solutions like #Query, constructor expressions and now, #NamedEntityGraph. My question is simply - does Spring data support such a shorthand syntax as I'm suggesting?
If not, perhaps this is a cool enhancement for a later version...
I'm not looking for workarounds.
You can use JPQL Constructor Expressions:
SELECT NEW com.company.PublisherInfo(pub.id, pub.revenue, mag.price)
FROM Publisher pub JOIN pub.magazines mag WHERE mag.price > 5.00
The constructor name must be fully qualified
If you want to return just 1 field from table and it's primitive(or autoboxing), you can use next:
#Query("select distinct t.locationId from Table t")
List<Long> findAllWashroomLocationId();
Where:
Table - name of class which represent your table
t - alias
locationId - name of field(in your Table object)
Long - type of locationId (Integer, String, ...)
Not sure if what you're trying to achieve is the same as using multiple projections on the same JPA generated query (where method name are the same). I have posted an answer in this post.
https://stackoverflow.com/a/43373337/4540216
So I've managed to figure out how to use multiple projections with a
single query.
<T> T getByUsername(String username, Class<T> projection) This allows the method caller to specified the type of projection to be
applied to the query.
To further improve this so it is less prone to error, I made a blank
interface that the projection will have to extend in order to be able
to insert class into the parameter.
public interface JPAProjection {
}
public interface UserRepository extends CrudRepository<UserAccount, Long> {
<T extends JPAProjection > T getByUsername(String username, Class<? extends JPAProjection> projection);
}
Projection Interface
public interface UserDetailsProjection extends JPAProjection{
#Value("#{target.username}")
String getUsername();
#Value("#{target.firstname}")
String getFirstname();
#Value("#{target.lastname}")
String getLastname();
}
Then I can call the query method by
getByUsername("...", UserDetailsProjection.class)
i have a nativequery,
this is a insert and i going to return all fields after insert whit "RETURNING *"
this query return all fields of my database, and this data going to save in my entity
"Perfil Detalles"
my entity have all configurations of my fields of my database
#Query(
value= "INSERT INTO \"USUARIO\".\"PERFIL_CONFIGURACION\" (id_perfil, id_group, id_role) VALUES(:id_perfil, :id_group, :id_role) returning *",
nativeQuery = true)
public PerfilDetalles insertPerfilDetalles(
#Param("id_perfil") Long id_perfil,
#Param("id_group") int id_group,
#Param("id_role") int id_role);