Related
I am looking into Spring Data JPA. Consider the below example where I will get all the crud and finder functionality working by default and if I want to customize a finder then that can be also done easily in the interface itself.
#Transactional(readOnly = true)
public interface AccountRepository extends JpaRepository<Account, Long> {
#Query("<JPQ statement here>")
List<Account> findByCustomer(Customer customer);
}
I would like to know how can I add a complete custom method with its implementation for the above AccountRepository? Since its an Interface I cannot implement the method there.
You need to create a separate interface for your custom methods:
public interface AccountRepository
extends JpaRepository<Account, Long>, AccountRepositoryCustom { ... }
public interface AccountRepositoryCustom {
public void customMethod();
}
and provide an implementation class for that interface:
public class AccountRepositoryImpl implements AccountRepositoryCustom {
#Autowired
#Lazy
AccountRepository accountRepository; /* Optional - if you need it */
public void customMethod() { ... }
}
See also:
4.6 Custom Implementations for Spring Data Repositories
Note that the naming scheme has changed between versions. See https://stackoverflow.com/a/52624752/66686 for details.
In addition to axtavt's answer, don't forget you can inject Entity Manager in your custom implementation if you need it to build your queries:
public class AccountRepositoryImpl implements AccountRepositoryCustom {
#PersistenceContext
private EntityManager em;
public void customMethod() {
...
em.createQuery(yourCriteria);
...
}
}
There's a slightly modified solution that does not require additional interfaces.
As specificed in the documented functionality, the Impl suffix allows us to have such clean solution:
Define in you regular #Repository interface, say MyEntityRepository the custom methods (in addition to your Spring Data methods)
Create a class MyEntityRepositoryImpl (the Impl suffix is the magic) anywhere (doesn't even need to be in the same package) that implements the custom methods only and annotate such class with #Component** (#Repository will not work).
This class can even inject MyEntityRepository via #Autowired for use in the custom methods.
Example:
Entity class (for completeness):
package myapp.domain.myentity;
#Entity
public class MyEntity {
#Id private Long id;
#Column private String comment;
}
Repository interface:
package myapp.domain.myentity;
#Repository
public interface MyEntityRepository extends JpaRepository<MyEntity, Long> {
// EXAMPLE SPRING DATA METHOD
List<MyEntity> findByCommentEndsWith(String x);
List<MyEntity> doSomeHql(Long id); // custom method, code at *Impl class below
List<MyEntity> useTheRepo(Long id); // custom method, code at *Impl class below
}
Custom methods implementation bean:
package myapp.infrastructure.myentity;
#Component // Must be #Component !!
public class MyEntityRepositoryImpl { // must have the exact repo name + Impl !!
#PersistenceContext
private EntityManager entityManager;
#Autowired
private MyEntityRepository myEntityRepository;
#SuppressWarnings("unused")
public List<MyEntity> doSomeHql(Long id) {
String hql = "SELECT eFROM MyEntity e WHERE e.id = :id";
TypedQuery<MyEntity> query = entityManager.createQuery(hql, MyEntity.class);
query.setParameter("id", id);
return query.getResultList();
}
#SuppressWarnings("unused")
public List<MyEntity> useTheRepo(Long id) {
List<MyEntity> es = doSomeHql(id);
es.addAll(myEntityRepository.findByCommentEndsWith("DO"));
es.add(myEntityRepository.findById(2L).get());
return es;
}
}
Usage:
// You just autowire the the MyEntityRepository as usual
// (the Impl class is just impl detail, the clients don't even know about it)
#Service
public class SomeService {
#Autowired
private MyEntityRepository myEntityRepository;
public void someMethod(String x, long y) {
// call any method as usual
myEntityRepository.findByCommentEndsWith(x);
myEntityRepository.doSomeHql(y);
}
}
And that's all, no need for any interfaces other than the Spring Data repo one you already have.
The only possible drawbacks I identified are:
The custom methods in the Impl class are marked as unused by the compiler, thus the #SuppressWarnings("unused") suggestion.
You have a limit of one Impl class. (Whereas in the regular fragment interfaces implementation the docs suggest you could have many.)
If you place the Impl class at a different package and your test uses only #DataJpaTest, you have to add #ComponentScan("package.of.the.impl.clazz") to your test, so Spring loads it.
The accepted answer works, but has three problems:
It uses an undocumented Spring Data feature when naming the custom implementation as AccountRepositoryImpl. The documentation clearly states that it has to be called AccountRepositoryCustomImpl, the custom interface name plus Impl
You cannot use constructor injection, only #Autowired, that are considered bad practice
You have a circular dependency inside of the custom implementation (that's why you cannot use constructor injection).
I found a way to make it perfect, though not without using another undocumented Spring Data feature:
public interface AccountRepository extends AccountRepositoryBasic,
AccountRepositoryCustom
{
}
public interface AccountRepositoryBasic extends JpaRepository<Account, Long>
{
// standard Spring Data methods, like findByLogin
}
public interface AccountRepositoryCustom
{
public void customMethod();
}
public class AccountRepositoryCustomImpl implements AccountRepositoryCustom
{
private final AccountRepositoryBasic accountRepositoryBasic;
// constructor-based injection
public AccountRepositoryCustomImpl(
AccountRepositoryBasic accountRepositoryBasic)
{
this.accountRepositoryBasic = accountRepositoryBasic;
}
public void customMethod()
{
// we can call all basic Spring Data methods using
// accountRepositoryBasic
}
}
This is limited in usage, but for simple custom methods you can use default interface methods like:
import demo.database.Customer;
import org.springframework.data.repository.CrudRepository;
public interface CustomerService extends CrudRepository<Customer, Long> {
default void addSomeCustomers() {
Customer[] customers = {
new Customer("Józef", "Nowak", "nowakJ#o2.pl", 679856885, "Rzeszów", "Podkarpackie", "35-061", "Zamknięta 12"),
new Customer("Adrian", "Mularczyk", "adii333#wp.pl", 867569344, "Krosno", "Podkarpackie", "32-442", "Hynka 3/16"),
new Customer("Kazimierz", "Dejna", "sobieski22#weebly.com", 996435876, "Jarosław", "Podkarpackie", "25-122", "Korotyńskiego 11"),
new Customer("Celina", "Dykiel", "celina.dykiel39#yahoo.org", 947845734, "Żywiec", "Śląskie", "54-333", "Polna 29")
};
for (Customer customer : customers) {
save(customer);
}
}
}
EDIT:
In this spring tutorial it is written:
Spring Data JPA also allows you to define other query methods by
simply declaring their method signature.
So it is even possible to just declare method like:
Customer findByHobby(Hobby personHobby);
and if object Hobby is a property of Customer then Spring will automatically define method for you.
Im using the following code in order to access generated find methods from my custom implementation. Getting the implementation through the bean factory prevents circular bean creation problems.
public class MyRepositoryImpl implements MyRepositoryExtensions, BeanFactoryAware {
private BrandRepository myRepository;
public MyBean findOne(int first, int second) {
return myRepository.findOne(new Id(first, second));
}
public void setBeanFactory(BeanFactory beanFactory) throws BeansException {
myRepository = beanFactory.getBean(MyRepository.class);
}
}
Considering your code snippet, please note that you can only pass Native objects to the findBy### method, lets say you want to load a list of accounts that belongs certain costumers, one solution is to do this,
#Query("Select a from Account a where a."#nameoffield"=?1")
List<Account> findByCustomer(String "#nameoffield");
Make sue the name of the table to be queried is thesame as the Entity class.
For further implementations please take a look at this
If you want to be able to do more sophisticated operations you might need access to Spring Data's internals, in which case the following works (as my interim solution to DATAJPA-422):
public class AccountRepositoryImpl implements AccountRepositoryCustom {
#PersistenceContext
private EntityManager entityManager;
private JpaEntityInformation<Account, ?> entityInformation;
#PostConstruct
public void postConstruct() {
this.entityInformation = JpaEntityInformationSupport.getMetadata(Account.class, entityManager);
}
#Override
#Transactional
public Account saveWithReferenceToOrganisation(Account entity, long organisationId) {
entity.setOrganisation(entityManager.getReference(Organisation.class, organisationId));
return save(entity);
}
private Account save(Account entity) {
// save in same way as SimpleJpaRepository
if (entityInformation.isNew(entity)) {
entityManager.persist(entity);
return entity;
} else {
return entityManager.merge(entity);
}
}
}
There is another issue to be considered here. Some people expect that adding custom method to your repository will automatically expose them as REST services under '/search' link. This is unfortunately not the case. Spring doesn't support that currently.
This is 'by design' feature, spring data rest explicitly checks if method is a custom method and doesn't expose it as a REST search link:
private boolean isQueryMethodCandidate(Method method) {
return isQueryAnnotationPresentOn(method) || !isCustomMethod(method) && !isBaseClassMethod(method);
}
This is a qoute of Oliver Gierke:
This is by design. Custom repository methods are no query methods as
they can effectively implement any behavior. Thus, it's currently
impossible for us to decide about the HTTP method to expose the method
under. POST would be the safest option but that's not in line with the
generic query methods (which receive GET).
For more details see this issue: https://jira.spring.io/browse/DATAREST-206
I liked Danila's solution and started using it but nobody else on the team liked having to create 4 classes for each repository. Danila's solution is the only one here that let's you use the Spring Data methods in the Impl class. However, I found a way to do it with just a single class:
public interface UserRepository extends MongoAccess, PagingAndSortingRepository<User> {
List<User> getByUsername(String username);
default List<User> getByUsernameCustom(String username) {
// Can call Spring Data methods!
findAll();
// Can write your own!
MongoOperations operations = getMongoOperations();
return operations.find(new Query(Criteria.where("username").is(username)), User.class);
}
}
You just need some way of getting access to your db bean (in this example, MongoOperations). MongoAccess provides that access to all of your repositories by retrieving the bean directly:
public interface MongoAccess {
default MongoOperations getMongoOperations() {
return BeanAccessor.getSingleton(MongoOperations.class);
}
}
Where BeanAccessor is:
#Component
public class BeanAccessor implements ApplicationContextAware {
private static ApplicationContext applicationContext;
public static <T> T getSingleton(Class<T> clazz){
return applicationContext.getBean(clazz);
}
public static <T> T getSingleton(String beanName, Class<T> clazz){
return applicationContext.getBean(beanName, clazz);
}
#Override
public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
BeanAccessor.applicationContext = applicationContext;
}
}
Unfortunately, you can't #Autowire in an interface. You could autowire the bean into a MongoAccessImpl and provide a method in the interface to access it, but Spring Data blows up. I don't think it expects to see an Impl associated even indirectly with PagingAndSortingRepository.
I faced with this using mongo and spring. So let's assume we use MongoRepository to provided base crud operations, and let's say we need to implement some custom criteria query operation using mongoTemplate. To achieve one interface to inject repository for crud and custom we need to specify:
Custom interface:
public interface UserCustomRepository {
List<User> findAllUsersBySomeCriteria(UserCriteriaRequest criteriaRequest);
}
UserRepository interface 'must' first extends UserCustomRepository and then MongoRepository
#Repository
public interface UserRepository extends UserCustomRepository, MongoRepository<User, ObjectId> {
}
UserRepositoryImpl must have the same name as what crud interface with *Impl suffix.
#Component
#NoArgsConstructor
#AllArgsConstructor(onConstructor = #__(#Autowired))
public class UserRepositoryImpl implements UserCustomRepository {
private MongoTemplate mongoTemplate;
#Override
public List<User> findAllUsersBySomeCriteria(UserCriteriaRequest criteriaRequest){
//some impl
}
}
Let's impl some service - here we inject only UserRepository interface and use methods from crud repository and custom class impl.
#Service
#NoArgsConstructor
#AllArgsConstructor(onConstructor = #__(#Autowired))
public class UserService {
private UserRepository userReposityry;
public List<User> getUserByCriteria(UserCriteriaRequest request) {
userRepository.findById(request.getUserId); // Crud repository method
userRepository.findAllUsersBySomeCriteria(request); // custom method.
}
}
I extends the SimpleJpaRepository:
public class ExtendedRepositoryImpl<T extends EntityBean> extends SimpleJpaRepository<T, Long>
implements ExtendedRepository<T> {
private final JpaEntityInformation<T, ?> entityInformation;
private final EntityManager em;
public ExtendedRepositoryImpl(final JpaEntityInformation<T, ?> entityInformation,
final EntityManager entityManager) {
super(entityInformation, entityManager);
this.entityInformation = entityInformation;
this.em = entityManager;
}
}
and adds this class to #EnableJpaRepositoryries repositoryBaseClass.
I use SimpleJpaRepository as the base class of repository implementation and add custom method in the interface,eg:
public interface UserRepository {
User FindOrInsert(int userId);
}
#Repository
public class UserRepositoryImpl extends SimpleJpaRepository implements UserRepository {
private RedisClient redisClient;
public UserRepositoryImpl(RedisClient redisClient, EntityManager em) {
super(User.class, em);
this.redisClient = redisClient;
}
#Override
public User FindOrInsert(int userId) {
User u = redisClient.getOrSet("test key.. User.class, () -> {
Optional<User> ou = this.findById(Integer.valueOf(userId));
return ou.get();
});
…………
return u;
}
I Have two repository interfaces that connect MongoDB and CouchBase :
public interface UserRepositoryMongo extends MongoRepository<User, Long> {
}
public interface UserRepositoryCouch extends CouchbasePagingAndSortingRepository<User, Long> {
}
Is there a way to interchangeably #Autowire these repositories into UserService on condition?
The condition will be inside property file : application.properties.
**Note :**
*These repositories can have custom methods too.*
We can use either ConditionalOnProperty or ConditionalOnExpression to switch between two different repository implementation.
If we want to control the autowiring with simple property presence/absence or property value, then ConditionalOnProperty can be used.
If complex evaluation is required, then we can use ConditionalOnExpression.
ConditionalOnProperty (presence/absence of a property)
#Qualifier("specificRepo")
#ConditionalOnProperty("mongo.url")
public interface UserRepositoryMongo extends MongoRepository<User, Long>{
}
#Qualifier("specificRepo")
#ConditionalOnProperty("couch.url")
public interface UserRepositoryCouch extends CouchbasePagingAndSortingRepository<User, Long>{
}
ConditionalOnProperty (based on value)
#ConditionalOnProperty("repo.url", havingValue="mongo", matchIfMissing = true) //this will be default implementation if no value is matching
public interface UserRepositoryMongo extends MongoRepository<User, Long> {
}
#ConditionalOnProperty("repo.url", havingValue="couch")
public interface UserRepositoryCouch extends CouchbasePagingAndSortingRepository<User, Long> {
}
ConditionalOnExpression
#ConditionalOnExpression("#{'${repository.url}'.contains('couch')}")
public interface UserRepositoryCouch extends CouchbasePagingAndSortingRepository<User, Long> {
}
UPDATE
Use CrudRepository/Repository type to inject based on your requirement.
public class DemoService {
#Autowired
#Qualifier("specificRepo")
private CrudRepository repository;
}
Based on bean created, either UserRepositoryMongo or UserRepositoryCouch will be autowired. Make sure only one bean is instantiated to avoid ambiguity error.
Another attempt to solve this problem.
Based on the property, the autowired customRepository will be an instance of SimpleMongoRepository or SimpleCouchRepository.
public interface CustomRepository extends CrudRepository<User, Long> {
User findByLastName(String lastName); //custom methods
}
#Qualifier("specificRepo")
#ConditionalOnProperty("mongo.url")
public interface UserRepositoryMongo extends MongoRepository<User, Long>, CustomRepository{
}
#Qualifier("specificRepo")
#ConditionalOnProperty("couch.url")
public interface UserRepositoryCouch extends CouchbasePagingAndSortingRepository<User, Long>, CustomRepository{
}
public class UserService {
#Autowired
#Qualifier("specificRepo")
private CustomRepository repository;
}
How to inject repository to generic class?
public class FruitComboBox<T extends Fruit> extends ComboBox {
#Autowired
private JpaRepository<T, Integer> repository;
...
}
public class FruitMarket {
#Autowired
FruitComboBox<Apple> appleCombobox; // Apple extends Fruit
#Autowired
FruitComboBox<Orange> orangeCombobox; // Orange extends Fruit
...
}
Also I have two repositories
#Repository
public interface AppleRepository extends JpaRepository<Apple, Integer> {
}
#Repository
public interface OrangeRepository extends JpaRepository<Orange, Integer> {
}
I suppose that the generic repository from FruitComboBox should be resolved as one of two existing repositories according it's T, and autowired by Spring.
The NoUniqueBeanDefinitionException: expected single matching bean but found 2 occurs at runtime (not at start of application). So I supposed that at runtime all the types are defined and Spring has known what concrete type is T.
Spring data needs to know at the bootstrap time the the entity the repository represents. That means you can not leave it with Generic Parameter during autowiring.
Create a separate interface like below.
#Repository
public interface MyGenericRepository<T> extends JpaRepository<T, Integer>{
}
Now you should be able to autowire it with a definite type (not generic type). This is as generic as it gets.
#Autowired
private MyGenericRepository<Apple, Integer> repository;
Above can not be left with generic parameter.
Reference http://docs.spring.io/spring-data/jpa/docs/1.6.5.RELEASE/reference/html/repositories.html
Also try to use Long for the ID's.
I would like to take advantage of Spring 4.0's support for autowiring of generic types but I would like to avoid having to create explicit concrete or anonymous classes for each type. To use an example, lets say I have an interface:
public interface Cache<T extends Entity>
And an abstract implementation of the interface:
public abstract class AbstractCache<T extends Entity> implements Cache<T>
{
#Autowired
private EntityDao<T> dao;
#Autowired
private List<CacheListener<T>> listeners;
...
}
And entity classes A to Z that implement Entity (e.g):
public class A implements Entity
public class B implements Entity
...
public class Z implements Entity
Is there a way I can create instances of Cache<A> through Cache<Z> such that I can autowire these generic types in other classes? E.g.
#Autowire
private Cache<Z> zCache;
I know I can achieve this by individually defining each bean, E.g.
#Bean
public Cache<Z> cacheZ() {
return new AbstractCache<Z> () {};
}
But I have been unable to come up with a way to do this for all Entity classes in a particular package. E.g.
public void registerEntityCaches (BeanFactory beanFactory) {
for (Class<? extends Entity> cls : entityPackage.getAllClasses()) {
beanFactory.registerBean(new AbstractCache<cls>() {});
}
}
Is something like this possible or do I have to define them individually?
I am looking into Spring Data JPA. Consider the below example where I will get all the crud and finder functionality working by default and if I want to customize a finder then that can be also done easily in the interface itself.
#Transactional(readOnly = true)
public interface AccountRepository extends JpaRepository<Account, Long> {
#Query("<JPQ statement here>")
List<Account> findByCustomer(Customer customer);
}
I would like to know how can I add a complete custom method with its implementation for the above AccountRepository? Since its an Interface I cannot implement the method there.
You need to create a separate interface for your custom methods:
public interface AccountRepository
extends JpaRepository<Account, Long>, AccountRepositoryCustom { ... }
public interface AccountRepositoryCustom {
public void customMethod();
}
and provide an implementation class for that interface:
public class AccountRepositoryImpl implements AccountRepositoryCustom {
#Autowired
#Lazy
AccountRepository accountRepository; /* Optional - if you need it */
public void customMethod() { ... }
}
See also:
4.6 Custom Implementations for Spring Data Repositories
Note that the naming scheme has changed between versions. See https://stackoverflow.com/a/52624752/66686 for details.
In addition to axtavt's answer, don't forget you can inject Entity Manager in your custom implementation if you need it to build your queries:
public class AccountRepositoryImpl implements AccountRepositoryCustom {
#PersistenceContext
private EntityManager em;
public void customMethod() {
...
em.createQuery(yourCriteria);
...
}
}
There's a slightly modified solution that does not require additional interfaces.
As specificed in the documented functionality, the Impl suffix allows us to have such clean solution:
Define in you regular #Repository interface, say MyEntityRepository the custom methods (in addition to your Spring Data methods)
Create a class MyEntityRepositoryImpl (the Impl suffix is the magic) anywhere (doesn't even need to be in the same package) that implements the custom methods only and annotate such class with #Component** (#Repository will not work).
This class can even inject MyEntityRepository via #Autowired for use in the custom methods.
Example:
Entity class (for completeness):
package myapp.domain.myentity;
#Entity
public class MyEntity {
#Id private Long id;
#Column private String comment;
}
Repository interface:
package myapp.domain.myentity;
#Repository
public interface MyEntityRepository extends JpaRepository<MyEntity, Long> {
// EXAMPLE SPRING DATA METHOD
List<MyEntity> findByCommentEndsWith(String x);
List<MyEntity> doSomeHql(Long id); // custom method, code at *Impl class below
List<MyEntity> useTheRepo(Long id); // custom method, code at *Impl class below
}
Custom methods implementation bean:
package myapp.infrastructure.myentity;
#Component // Must be #Component !!
public class MyEntityRepositoryImpl { // must have the exact repo name + Impl !!
#PersistenceContext
private EntityManager entityManager;
#Autowired
private MyEntityRepository myEntityRepository;
#SuppressWarnings("unused")
public List<MyEntity> doSomeHql(Long id) {
String hql = "SELECT eFROM MyEntity e WHERE e.id = :id";
TypedQuery<MyEntity> query = entityManager.createQuery(hql, MyEntity.class);
query.setParameter("id", id);
return query.getResultList();
}
#SuppressWarnings("unused")
public List<MyEntity> useTheRepo(Long id) {
List<MyEntity> es = doSomeHql(id);
es.addAll(myEntityRepository.findByCommentEndsWith("DO"));
es.add(myEntityRepository.findById(2L).get());
return es;
}
}
Usage:
// You just autowire the the MyEntityRepository as usual
// (the Impl class is just impl detail, the clients don't even know about it)
#Service
public class SomeService {
#Autowired
private MyEntityRepository myEntityRepository;
public void someMethod(String x, long y) {
// call any method as usual
myEntityRepository.findByCommentEndsWith(x);
myEntityRepository.doSomeHql(y);
}
}
And that's all, no need for any interfaces other than the Spring Data repo one you already have.
The only possible drawbacks I identified are:
The custom methods in the Impl class are marked as unused by the compiler, thus the #SuppressWarnings("unused") suggestion.
You have a limit of one Impl class. (Whereas in the regular fragment interfaces implementation the docs suggest you could have many.)
If you place the Impl class at a different package and your test uses only #DataJpaTest, you have to add #ComponentScan("package.of.the.impl.clazz") to your test, so Spring loads it.
The accepted answer works, but has three problems:
It uses an undocumented Spring Data feature when naming the custom implementation as AccountRepositoryImpl. The documentation clearly states that it has to be called AccountRepositoryCustomImpl, the custom interface name plus Impl
You cannot use constructor injection, only #Autowired, that are considered bad practice
You have a circular dependency inside of the custom implementation (that's why you cannot use constructor injection).
I found a way to make it perfect, though not without using another undocumented Spring Data feature:
public interface AccountRepository extends AccountRepositoryBasic,
AccountRepositoryCustom
{
}
public interface AccountRepositoryBasic extends JpaRepository<Account, Long>
{
// standard Spring Data methods, like findByLogin
}
public interface AccountRepositoryCustom
{
public void customMethod();
}
public class AccountRepositoryCustomImpl implements AccountRepositoryCustom
{
private final AccountRepositoryBasic accountRepositoryBasic;
// constructor-based injection
public AccountRepositoryCustomImpl(
AccountRepositoryBasic accountRepositoryBasic)
{
this.accountRepositoryBasic = accountRepositoryBasic;
}
public void customMethod()
{
// we can call all basic Spring Data methods using
// accountRepositoryBasic
}
}
This is limited in usage, but for simple custom methods you can use default interface methods like:
import demo.database.Customer;
import org.springframework.data.repository.CrudRepository;
public interface CustomerService extends CrudRepository<Customer, Long> {
default void addSomeCustomers() {
Customer[] customers = {
new Customer("Józef", "Nowak", "nowakJ#o2.pl", 679856885, "Rzeszów", "Podkarpackie", "35-061", "Zamknięta 12"),
new Customer("Adrian", "Mularczyk", "adii333#wp.pl", 867569344, "Krosno", "Podkarpackie", "32-442", "Hynka 3/16"),
new Customer("Kazimierz", "Dejna", "sobieski22#weebly.com", 996435876, "Jarosław", "Podkarpackie", "25-122", "Korotyńskiego 11"),
new Customer("Celina", "Dykiel", "celina.dykiel39#yahoo.org", 947845734, "Żywiec", "Śląskie", "54-333", "Polna 29")
};
for (Customer customer : customers) {
save(customer);
}
}
}
EDIT:
In this spring tutorial it is written:
Spring Data JPA also allows you to define other query methods by
simply declaring their method signature.
So it is even possible to just declare method like:
Customer findByHobby(Hobby personHobby);
and if object Hobby is a property of Customer then Spring will automatically define method for you.
Im using the following code in order to access generated find methods from my custom implementation. Getting the implementation through the bean factory prevents circular bean creation problems.
public class MyRepositoryImpl implements MyRepositoryExtensions, BeanFactoryAware {
private BrandRepository myRepository;
public MyBean findOne(int first, int second) {
return myRepository.findOne(new Id(first, second));
}
public void setBeanFactory(BeanFactory beanFactory) throws BeansException {
myRepository = beanFactory.getBean(MyRepository.class);
}
}
Considering your code snippet, please note that you can only pass Native objects to the findBy### method, lets say you want to load a list of accounts that belongs certain costumers, one solution is to do this,
#Query("Select a from Account a where a."#nameoffield"=?1")
List<Account> findByCustomer(String "#nameoffield");
Make sue the name of the table to be queried is thesame as the Entity class.
For further implementations please take a look at this
If you want to be able to do more sophisticated operations you might need access to Spring Data's internals, in which case the following works (as my interim solution to DATAJPA-422):
public class AccountRepositoryImpl implements AccountRepositoryCustom {
#PersistenceContext
private EntityManager entityManager;
private JpaEntityInformation<Account, ?> entityInformation;
#PostConstruct
public void postConstruct() {
this.entityInformation = JpaEntityInformationSupport.getMetadata(Account.class, entityManager);
}
#Override
#Transactional
public Account saveWithReferenceToOrganisation(Account entity, long organisationId) {
entity.setOrganisation(entityManager.getReference(Organisation.class, organisationId));
return save(entity);
}
private Account save(Account entity) {
// save in same way as SimpleJpaRepository
if (entityInformation.isNew(entity)) {
entityManager.persist(entity);
return entity;
} else {
return entityManager.merge(entity);
}
}
}
There is another issue to be considered here. Some people expect that adding custom method to your repository will automatically expose them as REST services under '/search' link. This is unfortunately not the case. Spring doesn't support that currently.
This is 'by design' feature, spring data rest explicitly checks if method is a custom method and doesn't expose it as a REST search link:
private boolean isQueryMethodCandidate(Method method) {
return isQueryAnnotationPresentOn(method) || !isCustomMethod(method) && !isBaseClassMethod(method);
}
This is a qoute of Oliver Gierke:
This is by design. Custom repository methods are no query methods as
they can effectively implement any behavior. Thus, it's currently
impossible for us to decide about the HTTP method to expose the method
under. POST would be the safest option but that's not in line with the
generic query methods (which receive GET).
For more details see this issue: https://jira.spring.io/browse/DATAREST-206
I liked Danila's solution and started using it but nobody else on the team liked having to create 4 classes for each repository. Danila's solution is the only one here that let's you use the Spring Data methods in the Impl class. However, I found a way to do it with just a single class:
public interface UserRepository extends MongoAccess, PagingAndSortingRepository<User> {
List<User> getByUsername(String username);
default List<User> getByUsernameCustom(String username) {
// Can call Spring Data methods!
findAll();
// Can write your own!
MongoOperations operations = getMongoOperations();
return operations.find(new Query(Criteria.where("username").is(username)), User.class);
}
}
You just need some way of getting access to your db bean (in this example, MongoOperations). MongoAccess provides that access to all of your repositories by retrieving the bean directly:
public interface MongoAccess {
default MongoOperations getMongoOperations() {
return BeanAccessor.getSingleton(MongoOperations.class);
}
}
Where BeanAccessor is:
#Component
public class BeanAccessor implements ApplicationContextAware {
private static ApplicationContext applicationContext;
public static <T> T getSingleton(Class<T> clazz){
return applicationContext.getBean(clazz);
}
public static <T> T getSingleton(String beanName, Class<T> clazz){
return applicationContext.getBean(beanName, clazz);
}
#Override
public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
BeanAccessor.applicationContext = applicationContext;
}
}
Unfortunately, you can't #Autowire in an interface. You could autowire the bean into a MongoAccessImpl and provide a method in the interface to access it, but Spring Data blows up. I don't think it expects to see an Impl associated even indirectly with PagingAndSortingRepository.
I faced with this using mongo and spring. So let's assume we use MongoRepository to provided base crud operations, and let's say we need to implement some custom criteria query operation using mongoTemplate. To achieve one interface to inject repository for crud and custom we need to specify:
Custom interface:
public interface UserCustomRepository {
List<User> findAllUsersBySomeCriteria(UserCriteriaRequest criteriaRequest);
}
UserRepository interface 'must' first extends UserCustomRepository and then MongoRepository
#Repository
public interface UserRepository extends UserCustomRepository, MongoRepository<User, ObjectId> {
}
UserRepositoryImpl must have the same name as what crud interface with *Impl suffix.
#Component
#NoArgsConstructor
#AllArgsConstructor(onConstructor = #__(#Autowired))
public class UserRepositoryImpl implements UserCustomRepository {
private MongoTemplate mongoTemplate;
#Override
public List<User> findAllUsersBySomeCriteria(UserCriteriaRequest criteriaRequest){
//some impl
}
}
Let's impl some service - here we inject only UserRepository interface and use methods from crud repository and custom class impl.
#Service
#NoArgsConstructor
#AllArgsConstructor(onConstructor = #__(#Autowired))
public class UserService {
private UserRepository userReposityry;
public List<User> getUserByCriteria(UserCriteriaRequest request) {
userRepository.findById(request.getUserId); // Crud repository method
userRepository.findAllUsersBySomeCriteria(request); // custom method.
}
}
I extends the SimpleJpaRepository:
public class ExtendedRepositoryImpl<T extends EntityBean> extends SimpleJpaRepository<T, Long>
implements ExtendedRepository<T> {
private final JpaEntityInformation<T, ?> entityInformation;
private final EntityManager em;
public ExtendedRepositoryImpl(final JpaEntityInformation<T, ?> entityInformation,
final EntityManager entityManager) {
super(entityInformation, entityManager);
this.entityInformation = entityInformation;
this.em = entityManager;
}
}
and adds this class to #EnableJpaRepositoryries repositoryBaseClass.
I use SimpleJpaRepository as the base class of repository implementation and add custom method in the interface,eg:
public interface UserRepository {
User FindOrInsert(int userId);
}
#Repository
public class UserRepositoryImpl extends SimpleJpaRepository implements UserRepository {
private RedisClient redisClient;
public UserRepositoryImpl(RedisClient redisClient, EntityManager em) {
super(User.class, em);
this.redisClient = redisClient;
}
#Override
public User FindOrInsert(int userId) {
User u = redisClient.getOrSet("test key.. User.class, () -> {
Optional<User> ou = this.findById(Integer.valueOf(userId));
return ou.get();
});
…………
return u;
}