Is there any chance that CDI and spring dependency injection could co-exist. The problem started when I tried using JpaRepository interface.
I cannot remove beans.xml as it breaks a common jar implementation which uses CDI. I tried #Vetoed but it then fails to autowire my JpaRepository interface in a service class. Does it mean that #Vetoed prevents the bean from being managed by spring also?
I am looking for an idea so that i could use CDI to manage some beans and spring to manage the rest.
Related
I have a CDI bean that is annotated with #ApplicationScoped. Is there a way to tell Spring to pick it up during component scan, as if it were annotated with #Component? Spring does understand the #Inject annotation so why not #ApplicationScoped?
The idea is that it would be handy to use CDI beans in Spring (at least if they only use plain dependency injection without the fancy CDI stuff like interceptors, decorators...)
It is not entirely clear how is your code structured, if possible just annotate it with #Component as well. A component bean in Spring has similar properties as an application scoped bean. The default scope of a bean in Spring is singleton and it can be proxied, similar to what #ApplicationScoped would offer.
Spring does understand the #Inject annotation so why not #ApplicationScoped?
Spring offers support for JSR 330 annotation, #ApplicationScoped is nor part of those.
I have 3 implementations of an interface, and in order to instantiate one of them I need to check a parameter from the database.
I was planning to do it with the factory pattern, but since I'm using JSF 2 dependecy injection in the rest of my application I was wondering if
there's a way to do that, is it possible to do the dependency injection dinamically?
can I indicate somehow a method or something to pick up the correct implementation at each moment?
For the backend I'm using spring core, so a way to do that with the spring context would work to.
I'm using Annotations for everything (#Autowired for Spring, #ManagedProperty for JSF).
EDIT: The project will be deployed on a Tomcat server.
I suggest you to use CDI in your JSF project, you can then use programmatic injection.
You should start with adding CDI Qualifiers to your interface implementations (you will basically create custom annotation for each implementation - tutorial). Then you can use something like
#Named //similar to ManagedBean
#RequestScoped
public Bean {
#Inject
#Any
Instance<YourInterface> yourInterface;
public void someMethod() {
if(someCondition) {
InterfaceImpl impl = yourInterface.select(new SomeOfYourQualifiers()).get();
}
}
}
Source
Also you you don't have to use Autowired in favour of Inject. I am also sure that there is some Spring way how to to this but I will leave that to some Spring expert here:-)
EDIT
According to this answer is really possible to run CDI on Tomcat. You will also find some tutorials like this one. And Spring approach could be using AutowireCapableBeanFactor but as I say, I don't know Spring much so it's just a wild gues:-)
I am using a #configurable annotated Vaadin controller together with my Spring context, and it is working fine - except when I need to restart Tomcat, and the sessions are deserialized. Then I get this for my Vaadin app:
org.springframework.beans.factory.wiring.BeanConfigurerSupport BeanFactory has not been set on BeanConfigurerSupport: Make sure this configurer runs in a Spring container. Unable to configure bean of type [web.vaadin.ui.BackOfficeApplication]. Proceeding without injection.
I am thinking that this can be because the vaadin app is reserializing before the spring bean factory has a chance to?
(I am using CTW - aspectj and Spring 3.1.1.RELEASE)
Note:
It seems in the log that these errors come before the "Root WebApplicationContext: initialization started". How can it be that the beans are being autowired before the context initialization is started?
I am not an expert on (de)serialization with Spring and Tomcat, and this is not an answer but might be a workaround.
If BackOfficeApplication is your Vaadin application then there is an alternative to using #Configurable on that class. Instead, create a per-Vaadin Application Spring application context XML file and add this to it to cause your BackOfficeApplication instances to be autowired, etc.:
<bean id="backOfficeApplication"
class="org.dellroad.stuff.vaadin.ContextApplication"
factory-method="get"/>
In general, #Configurable can be more troublesome than normal bean wiring because they require the configuration to occur at object construction rather than allowing the bean factory to do the wiring later on, where it may be better able to detect loops, enforce ordering, etc.
Ideally normal bean wiring should be used for singletons that are initialized once at the beginning of the application and #Configurable should be used for "on the fly" beans created randomly during normal operation.
In order to use the #Autowire annotation, the object where you use the annotation must come from the spring context.
JSF managed beans are created by JSF's IOC not Springs, therefor i cannot use #Autowire inside of them must must use faces-config.xml and managed properties.
I already setup an EL resolver that lets be have spring beans as managed properties, i want to take it one step further and get rid of the need to go into the faces-config.xml every time i need to autowire something. Is this possible?
Just annotate your managed beans with #Controller (or #Component), and #Scope("request") (or session) and add <context:component-scan> (if you haven't), and managed beans will automatically be detected as spring beans. And since you are already using the ELResolver, that should be it - you should be able to use #Autowired (or better - #Inject, if using spring 3.0).
You can use #ManagedProperty(#{'someBean'}) for autowire other beans in jsf bean
I'm developing a web application on Apache Tomcat 6 with Hibernate and Spring, I'm using different XML configuration files to define my Spring beans (like the Hibernate DAO, Quartz scheduler and some other stuff). All these files are loaded at Tomcat start up via web.xml (ContextLoaderListener).
Now I'm not sure what is the recommended way to get access to my beans.
Should I write on class which provides the BeanFactory for all classes which should use a bean, or is it the better way to load the BeanFactory in each class.
BeanFactory bf = (BeanFactory) ContextLoader.getCurrentWebApplicationContext();
One of the core ideas of the spring framework is to minimize dependencies between classes. You'll get the most benefit by using this concept throughout your whole project. Each and every backend object should be defined as bean and can therefore use the dependency injection automatism.
If some of your Beans need to access the ApplicationContext directly (eg for requesting all Beans implementing some marker interface) you can implement the ApplicationContextAware interface, so still no factory is needed.
Use dependency injection instead. Create getters & setters in each controller class, and use your *-servlet.xml to inject the required beans via the <property> tag. No factory needed!