currently, I have an import.sql with which I import some test data in my database. Now, I want to bring it to our production system and what I read so far is that I should not use the import.sql in production.
Therefore, I thought I can create something with #Postconstruct.
I, therefore, created in the main application class something like that:
#Autowired
ICreateUserAtStartup repo;
#PostConstruct
public void initIt() throws Exception {
Rolle r = new Rolle();
r.setBezeichnung("xxx");
r.setId(1L);
r.setCreatedAt(new Date(2019, 01, 14));
repo.insertRolle(1L, "xxx");
}
In an seperate file I created the following interface:
#Repository
public interface ICreateUserAtStartup {
#Modifying
#Query("insert into benutzer(id, created_at, anzeigename,
benutzername, dienstnummer, active, passwort) SELECT :id,
:created_At, :anzeigename, :benutzername, :dienstnummer, :active,
:passwort")
void insertBenutzer(#Param("id") Long id, #Param("created_at")
String created_at, #Param("anzeigename") String anzeigename,
String benutzername, String dienstnummer, Boolean active, String password);
#Modifying
#Query("insert into rolle(id, bezeichnung) SELECT (:id,
:bezeichnung)")
void insertRolle(#Param("id") Long id, #Param("bezeichnung")
String bezeichnung);
}
However, as soon as I try to autowire repo in my main class, I always get the following exception:
No qualifying bean of type 'x.y.z.repository.ICreateUserAtStartup' available
Why don't you just use a specific migration tool for this purpose like Flyway or Liquibase?
https://flywaydb.org/
https://www.liquibase.org/
The reason why it cannot be autowired is that you haven't implemented that interface and created a bean from the implementation. Of course you might think that if you just create an interface and annotate it with #Repository, it will work out of the box but that's not the case.
If you want to use Spring Data for your repository layer, you'll need an entity and you need to extend at least CrudRepository.
https://docs.spring.io/spring-data/jpa/docs/current/reference/html/#repositories
Related
In my legacy application, I have a country table, state table and a mapping table for country and state with few additional columns.
I have created an entity class like this.
class CountryStateMapping {
#Id
private long id;
private Long countryId;
#OneToOne
#JoinColumn(name="state_id")
private State state;
//getters seters
}
My repository.
public interface CountryStateMapping extends JpaRepository<CountryStateMapping, Long>{
Optional<CountryStateMapping> findByStateId(long stateId);
Optional<CountryStateMapping> findByState(State state);
}
I would like to check if the state exists in the mapping table. Both of the below approaches do not work.
countryStateMapping.findByStateId(long stateId)
countryStateMapping.findByState(State state)
What is the right way?
Its not the correct way i feel.The correct way for doing this will be
public interface CountryStateMappingRepository extends JpaRepository<CountryStateMapping, Long> {
Optional<CountryStateMapping> findByStateId(long stateId);
#Query("select s.something from State s" )
Optional<CountryStateMapping> findByState(State state);
}
This implies two things
By extending JpaRepository we get a bunch of generic CRUD methods to create, update, delete, and find
2.It allows Spring to scan the classpath for this interface and create a Spring bean for it.
Also you need some configuration.For that you need to create a configuration class to be used with your data source.You can find many examples to do the same and one such is https://www.baeldung.com/the-persistence-layer-with-spring-data-jpa.
You can also use custom queries and simple queries using the #Query annotation.
Thanks
Try with an underscore for id like below;
public interface CountryStateMapping<CountryStateMapping, Long>{
Optional<CountryStateMapping> findByState_Id(long stateId);
Optional<CountryStateMapping> findByState(State state);
}
I am able to get the property value in Spring classes like below:
#Value("${database.name}")
private String databaseName;
I have to execute a native query by joining different tables which are in different databases.
#Query(value="select t1.* FROM db1.table1 t1 INNER JOIN db2.table2 t2 ON t2.t1_id1 = t1.id1")
Instead of hard coding database names i.e., db1 and db2 here, I have to get them from properties file.
how to get the property value inside the #Query annotation in Spring Data JPA Repository ?
I don't know if it is possible, but if not, you can consider this approach:
Instead of using properties in Repository's #Query directly, you can use params in the query but when you call the actual method - you can provide values from .properties.
Imagine you have simple repository:
public interface UserRepository extends JpaRepository<User, Long> {
// query with param
#Query("select u from User u where u.lastname = :lastname")
User findByLastname(#Param("lastname") String lastname);
}
Then, let's say you have some Service or Controller where you need to use your Repository - you can inject properties there and pass them to your method:
#Service
public class UserService {
// this comes from .properties
#Value("${user.lastName}")
private String userLastName;
#Autowired
private UserRepository userRepository;
public User getUser() {
// you pass it as param to the repo method which
// injects it into query
return userRepository.findByLastname(userLastName);
}
}
This is just an example. But I believe it may be useful.
Happy hacking :)
I am using Spring Framework as my back end
I have define know as Entity class The Entity class know contain 5 Fields
Below is the class , The code below dose not have setter getter part to make shorter and cleaner
#Entity
#Table(name="TblKnow")
public class Know {
#Id
private Double idKnow;
private String SubjectKnow;
private String BodyKnow;
private String ImgKnow;
private double CountView;
In JpaRepository interface i want to only query two column not all of columns.
public interface KnowRepository extends JpaRepository<Know,Double> {
#Query("SELECT idKnow,SubjectKnow FROM Know")
public Page<Know> findCByOrderByIdKnowDesc(Pageable pageable);
Problem: i try to run but i get below exception
java.lang.IllegalArgumentException: Cannot create TypedQuery for query with more than one return using requested result type [java.lang.Long]
But if i use without below query it is fine
public Page<Know> findAllByOrderByIdKnowDesc(Pageable pageable);
You can create a custom constructor and use that to select only some fields in JPA query.
public Know(Double idKnow, String SubjectKnow) {
this.idKnow = idKnow;
this.SubjectKnow = SubjectKnow;
}
And the use this constructor in JPA query. Make sure you use complete path of class with package.
#Query("SELECT NEW packagePath.Know(idKnow,SubjectKnow) FROM Know")
query :
public Page<Know> findAllByOrderByIdKnowDesc(Pageable pageable);
works dut to you select Know objects with fields that are mapped correct into Know class (and after wrapped into Page).
with query :
#Query("SELECT idKnow,SubjectKnow FROM Know")
public Page<Know> findCByOrderByIdKnowDesc(Pageable pageable);
returns some custome bean/object that spring data can't map in correct way into Know class (as you declared it as expected return class wrapped into Page). add counstructor into Know with idKnow,SubjectKnow fields , or you can wrap it into some DTO with idKnow,SubjectKnow fields.
I have a domain object which looks like this.
i need to use the data fetched from the database ("type" in this example) to fetch and inject the correct type of service.
I get this output which means that the DB data are not set during the call :
entity is a bean postconstruct: PocProduct [id=null, type=null, productName=null].. attching behavior!
I get the same resilt when I try with the initializing Bean.
What is the correct way to configure this?
#Entity
#Table(name = "AAA_POC_PROD")
#Configurable(dependencyCheck = true)
#Scope("prototype")
public class PocProduct implements Serializable, InitializingBean {
/**
*
*/
private static final long serialVersionUID = 1136936011238094989L;
#Id
private String id;
private String type;
private String productName;
#Transient
private Behaviour behaviour;
#Transient
#Autowired
private BehaviourFactory behaviourFactory;
//getters and setters
#PostConstruct
public void attachBehavior() {
System.out.println("entity is a bean postconstruct: " + this + ".. attching behavior!");
//Need to call this : depends on type which is fetched from DB
// this.behaviour = behaviourFactory.getTypeBasedBehaviour(type);
}
}
Configurable beans are initialized by Spring after or before construction, depending on the value of the #Configurable.preConstruction attribute. When loading an entity from a database this means the following sequence of events:
The JPA provider creates the entity by invoking it's constructor via reflection
While the constructor executes, spring-aspects' AnnotationBeanConfigurerAspect intercepts the constructor execution and, before (or after) the constructor executes, Spring will configure this newly created object by executing any bean configuration you have in your spring context, including autowiring of properties.
The JPA provider will receive this object already configured by Spring and will start populating its persistent properties with data fetched from the DB.
Optionally, if you set up #PostLoad methods, the JPA provider will invoke these methods so that your entities have a chance to do work after the entity is fully populated by data from the DB.
From what I see you're trying to do, this 4th step is where you should put your custom behavior logic, assuming everything else is working properly.
I am new to SpringData and I am not getting what is happening here. I have created an Interface that extends PagingAndSortingRepository and overrided the findAll() method like this:
#Override
#Query
List<MyEntity> findAll();
I am calling this method in my service, but it is making my app to throw an exception Caused by: java.lang.StackOverflowError because that method is reading through the entire database, not only from MyEntitytable in database. Any idea?
Apparently the problem is in the configuration of EclipseLink. In persistence.xml I added this row <shared-cache-mode>NONE</shared-cache-mode> and now it works as it should.
no need to override getall() method.in your service autowired that dao or repository class and using this you can directly call the findall() method.
in the case you want to write your custom method apart from what given by spring data jpa then we use the #Query to write custom query.
No Need to Override. What i have done is i have created a repository i.e
FavoriteRepository which is extending JpaRepository and i have mentioned the
dbmodel name (Favorite)
like this JpaRepository<Favorite, Long> // Here Favorite is my model name
and Long is the type of primary key mentioned in db model Favorite as #Id
#Repository
public interface FavoriteRepository extends JpaRepository<Favorite, Long>{
}
Now you can use method findOne or findAll. As these methods are present in
Jparepository.Hope so it will help
If you want to add new method then use #Query with JpQL
#Query(value = "select f from Favorite f where f.userId=:userId ")
public List<Favorite> getFavoritesForUser(#Param("userId") String userId);