#Service
#Transactional
public CarService {
#Autowired private CarRepository carRepository;
#Cachable("cars")
public List<Car> getCars() {
return carRepository.getAll();
}
}
Suppose I have a code like this, where both #Transactional and #Cachable are presented. How can I guarantee that proxy chain spring will go through will be proxyForCache-proxyForTransaction? I.e. transaction won't be created, if my application already has cached result. I've seen a lot of examples, where people offer to implement Ordered interfaface on a class-level, namely, on #Aspect level. But problem is we don't use AspectJ in our project. Is there any way to order spring proxies without creating additional classes or at least using of AspectJ?
Related
I have many different SpringBoot tests running. So far the auto configuration slices were really helpful, especially in combination with #MockBean.
But in my current test no such slice fits and booting up the complete context using #SpringBootTest is too slow.
Is there a way to manually set the tip of the object tree to be started with and from there spring autowires all needed beans? Or is there a way to set all needed beans manually?
In my specific case i want to test a MapStruct generated mapper (using componentModel = "spring") this mapper uses two other mappers, each injecting a service to do their work.
The services are provided via #MockBean:
#RunWith(SpringRunner.class)
#SpringBootTest
public class ProductResponsibleUnitMapperTest {
#Autowired
private PRUMapper mapper;
#MockBean
private TradingPartnerService tradingPartnerService;
#MockBean
private ProductHierarchyService productHierarchyService;
#Test
public void mapForthAndBack(){
//works but takes ages to boot
}
}
I could not use constructor injection on the mappers (for the services) because MapStruct won't generate correct implementations.
How to get a Spring-Context only containing the needed beans?
I found one way by explicitly declaring all implementation used:
#SpringBootTest(classes = {ProductResponsibleUnitMapperImpl.class, LegalEntityMapperImpl.class, ProductHierarchyMapperImpl.class})
For more complex setups it will be cumbersome and also dangerous to declare generated classes.
I am still searching for a better cleaner way to let Spring decide what classes needed. It should be possible to set the class in hand and let Spring decide what classes needed and to be instantiated.
I use Spring(Service Layer and Repository) to do CRUD operations on a mysql database.
MyServiceImpl :
#Service
#Transactional
public class MyServiceImpl implements MyService {
private final MyRepository myrepo;
....
#Transactional(readOnly = true)
public Optional<myObj> findOne(Long id) {
return myrepo.findById(id);
}
}
is the using of readonly=true for read operations a bad practice? what about performance?
This is a good optimization practice. You can find the examples in the Spring Data documentation. And you won't need to annotate your whole service with #Transactional annotation because "..CRUD methods of the Spring Data JPA repository implementation are already annotated with #Transactional"
Getting started with Spring Data JPA
To start with, since Spring doesn't do persistence itself, so readonly is only a hint to the provider for behaviour(e.g Hibernate)
As per Hibernate's behavior readonly=true will set FlushMode.NEVER in current session which will prevent committing the transaction.
If you don't explicitly set readOnly to true, you will have read/write transactions.
Now coming Back to your Question
Looking at your findOne method. Looks like you are doing a Read call from database.
So its good to mark it as readonly to let your Provider know you are reading only.
You can read more in Detail here
https://docs.spring.io/spring/docs/3.0.x/spring-framework-reference/html/transaction.html
Spring #Transactional read-only propagation
I'm using Spring's CrudRepository in combination with the annotation #RepositoryRestResource to implement a simple CRUD-app that can be used throught a RESTful API. I now want to add an AspectJ pointcut on my repository, so that some functionalities will be executed whenever a CRUD-method from the interface is called.
First, I extend Spring's CrudRepository to add some custom functionalities in my own interface:
#RepositoryRestResource(collectionResourceRel = "customers", path = "customers")
public interface CustomerRestRepository extends CrudRepository<Customer, Integer>{
Customer findOneByGuid(#Param("customerGuid") String customerGuid);
//Other custom methods.
}
Everything is working fine and I'm able to call this method via my REST client. I do not have to implement the interface CustomerRestRepository since Spring is doing the job as a miracle in behind. This is one of the crucial advantages of extending Springs's CrudRepository.
The problem, I'm facing now, is to add an AspectJ pointcut on this custom method findOneByGuid() that will, for example, log every call of the method after it's execution.
What I've tried by so far is:
#Aspect
public aspect AfterCustomerCrudAspect {
#Pointcut(
"execution(* com.x.y.z.CustomerRestRepository.findOneByGuid(..))")
public void customerCrudMethod() {}
#AfterReturning("customerCrudMethod()")
public void doSomething() {
//Do something
}
}
I've also tried:
1) execution(* com.x.y.z.CustomerRestRepository+.findOneByGuid(..))
2) execution(* org.springframework.data.repository.Repository+.*(..))
3) within(com.x.y.z.CustomerRestRepository)
4) annotation(RepositoryRestResource)
...and many others I do not remember. All with the same frustrating result: The advice is never applied.
By the way, I do not face any exceptions and if I try execution(* *.*(..)), the advice is working well - but, of course, not limited to the method findOneByGuid(). Thus, I think my code is correct in general.
I know that it is not possible to set pointcuts on interfaces. But since I do not have to implement the interface CustomerRestRepository by my own to get things working, I need to find a way to set a pointcut on an interface's method - or to find some other solution.
Well, one possible solution to that would be to implement the interface CustomerRestRepository. But then I've to do all the implementation work for the repository by my own and skip using the advantages of Spring's CrudRepository.
Thus, my question is, if there is a possibility to set a AspectJ pointcut on methods in a Spring CrudRepository.
Many thanks in advance for all the answers.
Well, I solved my problem in a different way.
Sometimes, things are less complicated than expected. Adding an AspectJ pointcut on a Spring CRUD-repository to execute some functionalities, whenever an entity is changed was not the best idea. (And at the best of my knowledge, it is not possible at all.)
There is a much more easier way to implement my requirement: The package javax.persistence provides the annotation #EntityListeners that suites perfectly to this job. So, annotate the entity class with the listener and implement the needed functionalities within the listener class:
#Entity
#EntityListeners(CustomerEntityListener.class)
//#Table, #NamedQueries and other stuff ...
public class Customer implements Serializable {
...
}
Implementation of the EntityListener:
public class CustomerEntityListener {
#PostPersist
public void customerPostPersist(Customer customer) {
//Add functionalities
}
}
The EntityListeneralso provides annotation for #PostUpdate, #PostRemove and so on - visit this site for more information.
I use spring annotation to manage java bean, use #service in service layer, and #autowired when inject service, but now I have a question, how to manage POJO by spring?
for example, I need to return a user for ajax call, so I need to always write like:
User user = new User()......
return user;
So, how I can use like
#autowired User user;
And the User POJO will be:
#component
#scope("prototype")
public class User{}
so each time the user entity will be a new one, and I needn't to new it everytime,
But I failed to write like this, so can spring manage POJO to be a prototype?
Update====================================
Thanks for answering
You have three options that i can think of straigh away. What you want is to be able to create prototypes from within a singleton. So you can either use..
1) AOP Scoped Proxy.
So change your User class annotation to ...
#Scope(value = "prototype", proxyMode = ScopedProxyMode.TARGET_CLASS)
(this required cglib on your classpath)
or
2) lookup-method
this is a bit more involved and makes things a bit harder to test
or
3) make your class implement ApplicationContextAware and then you can just call getBean on the context when you want a new prototype.
A bit of googling will sort you out anyway but I recommend the first option
Try following code:
#Component
#Scope(BeanDefinition.SCOPE_PROTOTYPE)
public class User
{
......
}
Hope it helps.
In my project I have an interface annotated with org.springframework.stereotype.Service tag.
I have two different implementation for this interface.
In my manage bean, I am injecting interface Service class and using its methods.
Now my requirement is, in run time I have to pick particular implementation (lets say based on login user group) so that respective logic can be invoked.
As per my understanding, we can achieve this using Factory pattern in java and achieve the same.
How can we implement this in SPRIng???
Besides suggested related topic above, there is a good thread on JavaRanch.
You can use
#Qualifier("myServiceImpl1") annotation together with #Autowired. In
that case this particular implementation of the interface will be
injected. You should also use the same name with your #Component,
#Service or #Repository annotations e.g.
#Service("myServiceImpl1")
public class MyServiceImpl1 implements MyService{}
public class Consumer{
#Autowired
#Qualifier("myServiceImpl1")
public MyService myServiceImpl1;
}
#Primary together with #Component, #Service or #Repository
annotations in your implementation class, in that case this
implementation will be injected by default.
If you mark a list of some interface type with #Autowired, all
available implementations of this interface will be injected.
#Autowired
public List<MyService> allAvailableImplementations;