I used to use hibernate native bootstrapping approaches, where I would like to add some customized things such as triggers, customized indexes etc.
Specifically, something like this:
Configuration configuration = new CustomConfiguration().configure()
.addAnnotatedClass(XXXXX.class)
...;
configuration.addAuxiliaryDatabaseObject(...); // add some customzied triggers and index here
// use this configure to create a hibernate native SessionFactory
Now our team is migrating to JPA standard APIs, so I'm wondering how should I do this with standard JPA's EntityManagerFactory?
The AuxiliaryDatabaseObject I used is a very hibernate-specific thing....so I guess the only way I do this is to get some hibernate delegate from EntityManagerFactory and do a hybrid bootstrapping....
Create a custom org.hibernate.boot.spi.MetadataContributor and register that as service through the Java service loader mechanism by adding a file META-INF/services/org.hibernate.boot.spi.MetadataContributor with the fully qualified name of your class as content.
This service will be picked up during boot automatically. In that class, you can add your auxiliary objects.
Related
So, I have an application running on WildFly10, which uses JSF, Spring (DI), JPA, Spring Data;
Right now we're trying to move it to CDI and remove Spring(DI). For now we'll keep Spring Data.
So, I set up CDI and made an EntityManager producer.
#Produces
#Dependent
#PersistenceContext
public EntityManager entityManager;
So, I'm able to inject repositories with CDI and all.
However on my original environment we had a custom repository factory,that was defined in my SpringConfiguration like this:
#EnableJpaRepositories(basePackages = {"com.foo.repository" }, repositoryFactoryBeanClass=CustomJpaRepositoryFactoryBean.class)
So, the question is, how can I define this repositoryFactoryBeanClass=CustomJpaRepositoryFactoryBean.class on a CDI environment?
The current implementation doesn't allow the configuration of the JpaRepositoryFactoryBean as one can see from the code where it gets instantiated.
So I guess you have the following options:
reimplement the instantiation process.
open a feature request.
do 2. and 1. in a reusable way and submit the result as a PR for the issue.
When trying to solve this problem I found that the custom impl was not being picked up. The solution suggested in this question helped me however: https://stackoverflow.com/a/38541669/188624
Basically is uses Java8 default interface method to provide the additional functionality. I had to use the "CDI.current().select" method to get hold of the entity manager though as property injection of course won't work.
I tested with Spring Data JPA 2.0.0
This is with reference to JPA 2.0: Adding entity classes to PersistenceUnit *from different jar* automatically and Unable to call Hibernate/QueryDSL from another maven subproject
It seems that Hibernate 4 had a great way to dynamically load entity classes using
org.hibernate.integrator.spi.Integrator service.
Now when using Hibernate 5, the Integrator interface's integrate method gives me
public void integrate(Metadata metadata, SessionFactoryImplementor sessionFactory,
SessionFactoryServiceRegistry serviceRegistry)
{
}
Where metadata is of type org.hibernate.boot.Metadata
I am unable to call addAnnotatedClass(), neither I am able to obtain the original Configuration object that was there in Hibernate 4.
How do I get around with this?
I am using maven and jetty.
I am not using spring (so please do not provide any spring based solution)
This was actually related to something I was wrestling with over the weekend in getting caught up on Hibernate 5. You can read about the planned changes related to the Configuration class in the latest Javadoc for Hibernate 4. The new place for getting info on all loaded entity classes including annotated entities is the Metadata class you mentioned. It has a getEntityBindings() method that will return the PersistentClass entity metadata representation for known all entities. This Collection is immutable however.
Recommendation is that you rethink using an Integrator to add entity bindings at runtime. This may have worked in the past, but the docs clearly point towards that not being intentional as this should be done at the time of initialization. The Metadata and SessionFactoryImplementor are for the most part immutable once built, and so the Integrator's intended purpose is not to modify these configuration items but instead use them as information on how to configure new Service integrations using the SessionFactoryServiceRegistry.
And if you're finding it annoying to configure your Session to find all your annotated classes at runtime, I suggest you try using the EntityManagerFactory approach for initializing Hibernate as it is far more straightforward and uses standard JPA syntax that can be switched to a handful of other providers if you ever need to. This will automatically scan for annotated entities on your behalf. The API is a bit more simplified and limited, but if you really ever need the power of native Hibernate-specific functionality there is a way to access the native underlying API.
I've set up Spring Roo following some basic guides, and I have a setup where data from my database can be accessed from a web browser using Roo's standard forms (like in this Youtube video). Now I'd like to access that data from Java code so I can "inject" it into a view from other pages on the site. How is this done?
Edit: Here's how I was able to access my data: From a controller (or any class, really), I use the this annotation along with this property definition:
#PersistenceContext
private EntityManager manager;
Then I can access the data with a query like this:
List<Announcement> results = manager.createQuery("from Announcement a where a.id = :id").setParameter("id", new Long(1)).getResultList();
This will give you a List of type Announcement (which is just an entity I created). Of course this query will yield only one result (or zero if the database doesn't have an entry with an id of 1). Thanks Micha for this solution.
You can use the #PersistenceContext annotation to get a JPA EntityManager instance in your application. Using the EntityManager you can query the database (like showed here). Since you are using Roo the entityManagerFactory bean and transaction support should already be included in your bean configuration file.
You can also use Spring data repositories to access your data.
Maybe this video can help you.
I'm looking into using JSR-303 with hibernate validator. We would like to be able to have different validations per each customer or have a base set of constraints and allow them to be overridden.
I'm not sure what's the best way to do this.
Using annotations for constraints is not suitable since they're essentially hard-coded in the models. I know I can use XML to externalize the validations (creating META-INF/validation.xml which specifies constraint-mapping files). But I'm not really sure how to easily make this configurable for multiple customers.
I suppose I would like to be able to set a simple property so that when we deploy it uses a completely different set of constraint-mapping files.
Any ideas?
You could create a ValidatorFactory per customer which you configure with customer-specific constraint mapping XML files like this:
ValidatorFactory validatorFactory = Validation
.byDefaultProvider()
.configure()
.addMapping(...) //input stream with an XML constraint mapping
.addMapping(...) //another input stream with an XML constraint mapping
.buildValidatorFactory();
When you're working with Hibernate Validator, you could also use the API for programmatic constraint declaration to create individually configured validator factories.
Similar topics have been covered in other threads, but I couldn't find a definitive solution to my problem.
What we're trying to achieve is to design a web app which is able to:
read a datasource configuration at startup (an XML file containing multiple datasource definitions, which is placed outside the WAR file and it's not the application-context or hibernate configuration file)
create a session factory for each one of them (considering that each datasource is a database with a different schema)
switch at runtime to different datasources based on user input (users can select which datasource they want to use)
provide the correct dao object to manage user requests.
At the moment we have a DAO Manager object which is able to read the datasource configuration file and instantiate multiple session factories, saving them in a map. Each session factory is created with a configuration containing the proper hibernate mapping classes (different for each database schema). Moreover we have multiple DAO interfaces with their implementations, used to access "their database".
At this point we would need a way to get from the DAO Manager a specific DAO object, containing the right session factory attached, all based on the user request (basically a call from the above service containing the datasource id or a custom datasource object).
Ideally the service layer should use the DAO Manager to get a DAO object based on the datasource id (for instance), without worrying about it's actual implementation: the DAO Manager would take care of it, by creating the correct DAO object and injecting in it the right session factory, based on the datasource id.
My questions are:
Is this a good approach to follow?
How can I use Spring to dynamically inject in the DAO Manager multiple DAO implementations for each DAO interface?
Once the session factories are created, is there a way to let Spring handle them, as I would normally do with dependency injection inside the application-context.xml?
Would the 2nd Level Cache still work for each Session Factory?
Is this a good approach to follow?
It's probably the only possible approach. So, yes.
How can I use Spring to dynamically
inject in the DAO Manager multiple DAO
implementations for each DAO
interface?
Dynamically? I thought you wanted to do it at startup time. If so, just provide an accessor with a list or array:
public void setMyDaos(List<Mydao> daos){
this.daos = daos;
}
Once the session factories are
created, is there a way to let Spring
handle them, as I would normally do
with dependency injection inside the
application-context.xml?
This one's tough. I'd say you will probably have to store your sessionFactory bean in scope=session