We have a spring app that works with mongodb.
Now we need it to connect also to mysql.
All the beans are defined in a applicationContext.xml legacy file.
We like that the new mysql configuration will be in java classes.
We created an entity, repository and a configuraion java files.
But it seems that as we try to do so, spring gets confused.
If we try to run the app, it start complaining about the mongo repositories:
Error creating bean with name 'MyMongoRepository': Could not resolve matching constructor (hint: specify index/type/name arguments for simple parameters to avoid type ambiguities
In the intellij we have the "could not autowire" error only on the sql repository (the first 3 are the mongo repositories):
Is it possible that the #configuration class is clashing with the applicationContext?
Should the #configuraion class be in a certain package/folder to work correctly?
Also, in the #configuration file, as there are green beans on the left side, it seems like intellij is able to understand where is the persistence repository.
Thanks for any help.
Related
I'm very new to spring boot and was trying to use entity manager. When I saw the examples online, I almost always saw #PersistenceContext(unitName="unit_name") annotation on top of the entity manager instance created; what goes inside the unitName? Is it the name of the database I'm trying to connect to?
As per the documentation Javadoc Link
unitName
(Optional) - The name of the persistence unit as defined in the persistence.xml file.
If there is a persistence.xml file in the project, so you can specify this argument just like it's in the file. It's an optional parameter, so it's auto-selected if not informed.
I have written some code in order test integration with mongoDB. Please find the link to the main method for running this spring boot application below,
https://github.com/siva54/simpleusercontrol/blob/master/src/main/java/com/siva/UserManagementApplication.java
From what I have read, An application should contain any of the configurations from the following URL to declare how the applications manages the context,
http://docs.spring.io/autorepo/docs/spring-boot/current/reference/html/using-boot-using-springbootapplication-annotation.html
I haven't used any of those contexts, However my application works fine and I'm able to run it without any issues. Am I missing something here? Can you please help with the info of how my application is able to start and manage the context/dependencies automatically?
Thanks in advance
#SpringBootApplication is equivalent of #Configuration, #EnableAutoConfiguration and #ComponentScan. Let's consider why your application works without of any of this three annotations.
Why it works without #Configuration:
When Spring will scan packages, it will find all classes marked by #Configuration and will use them as part of configuration. But in next line you manually passed UserManagementApplication as configuration source:
SpringApplication.run(UserManagementApplication.class, args);
So spring doesn't need to find this class by scan. Therefor it is not necessary to mark it by #Configuration.
Why it works without #ComponentScan:
Class UserManagementApplication has #ImportResource("classpath:spring/application-context.xml") annotation. That means file spring/application-context.xml will be included into configuration. And this file contains next line:
<context:component-scan base-package="com.siva.*" />
So, you don't need use annotation for scan packages, because you already declared it in the xml file.
Why it works without #EnableAutoConfiguration:
This annotation allows to Spring to try guess and configure the components automatically. For example, if you include the following dependency in your build.gradle:
dependencies {
compile 'org.springframework.boot:spring-boot-starter-data-mongodb'
}
Spring configures all the components required to work with MongoDB automatically. And all you need just specify host and user/pass in the aplication.proprties file.
But you preferred to declare all needed beans manually in the spring/application-context.xml file. So, you simply don't need #EnableAutoConfiguration annotation at all.
I use Play Framework + Spring Data JPA from this example:
https://github.com/typesafehub/play-spring-data-jpa
I have models, repositories and now I want to initialize my DB on start up. I inject repositories to my Global.java file using #Autowired, but they equals to null on run time. It's because Spring don't try to inject dependencies to Global.java, because Global.java don't have even package name, so I can't tell Spring to scan his package!
With controllers Spring DI works well, but how to use it in Global.java? How to initialize database using repositories?
You can change package of Global.java in application.conf by setting property application.global.
Other way can be to fetch dependency explicitly calling
context.getBean(YourBeanClass)
in Global.java instead of autowiring it, as you have context available in Global.
You may explicitly create a bean by defining it in your context xml
<bean id="global" class="Global"></bean>
Also, having classes in default packages is not a good idea.
I went through the Data Access With Spring tutorial and the in memory database they use in step 3 is working. But, I'm not clear on what I need to add/change to get it to query my development (Oracle) database now?
I want to use Hibernate, do I still need this JPAConfiguration class or would I have something Hibernate specific?
Please don't just post a link to the Hibernate reference. I'm reviewing that as well, but since I'm also using Spring, it's not clear to me the proper way to load the hibernate.cfg.xml and inject the Hibernate session in that context.
Don't be blocked by the fact that the class is called JPAConfiguration. You need to understand what the class does. Note that it has the annotation #Configuration which you can use along with AnnotationConfigApplicationContext to produce a Spring bean context.
That functionality is described in the Spring documentation for The IoC container.
What you need to change is how your DataSource and EntityManagerFactory beans are created. You'll need to use a DataSource that gets Connection instances from a JDBC Driver that supports Oracle databases.
TeamCity seems not to recognize Spring Data Repository beans when running the inspections. It works perfectly in IntelliJ IDEA but not in TeamCity.
I receive the following inspection problems:
Warning This custom Spring bean has not yet been parsed And it points to this XML element:
<jpa:repositories base-package="my.base.package" />
And then (obviously) an Error: Could not autowire. No beans of 'MyRepository' type found.
MyRepository extends the Spring Data CrudRepository interface.
As far as I understand, TeamCity launches an IntelliJ instance when running the inspections. Do I have to specify in some way which plugins (Spring Data) IntelliJ has to use when it's running the inspections?
I also tried multiple times to hit the check/reparse button in TeamCity...
Thanks for your help!