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In spring, is there a way to autowire the first bean?

In the example below, is there a way to avoid doing a context.getBean()? All the other beans subsequently used by the testService get autowired. (It is a console application)
public class Test {
private static ITestService testService;
private static ApplicationContext context;
public static void main(String[] args) {
context = new ClassPathXmlApplicationContext(
new String[]{"/META-INF/spring/app-context.xml"});
ITestService testService = context.getBean(ITestService.class);
}
}
I tried adding autowire annotation to ApplicationContext, but it didnt work. Besides how does it know where my app-context.xml is located if I autowire it?
Update: I found what I needed over here

Right, you're missing out a few details here.
Below is a short explanation of how Spring works.
1- The application context is loaded somehow (we will get there soon).
2- After loaded, app context will initialize/create all beans defined. Here is when beans get injected as dependencies. After this Whenever you get a bean back from the app context, that bean is all initialized and ready to go with all the dependencies in place (considering everything went fine).
RE the first step, there are a few way to automate the Spring initialization.
One way is what you are doing, explicitly instantiating one. Other way could be via a context listener in case you're in a web environment, or maybe with the #RunWith. (You can find more here)
In your case, I believe you are looking for using Spring in a (Unit?!?) test environment so you are looking for something like
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration
public class MyTest {
#Autowired
private ApplicationContext applicationContext;
// class body...
}
further details here
http://docs.spring.io/spring/docs/current/spring-framework-reference/htmlsingle/#testing

You cannot call beans without initializing the application context first.
Secondly in your case Test class should be bean itself to be managed by spring then to autowire ITestService. The purpose of Application context as a container is to manage the bean lifecycle so u need to initialize it first by ClassPathXmlApplicationContextand then it will initialize all beans declared by you in ur xml file. About avoiding the getBean method if you are using servlets for creating web app you can avoid getBean. If not you should handle it manually.

I agree with what #Desorder has said. When I started working with #RunWith(SpringJUnit4ClassRunner.class) and #ContextConfiguration, I used to get my test cases working. But it took me some time to understand how these two are working internally and their default configurations.
If you would like to take some different approach and would like to try without #RunWith and #ContextConfiguration, take a look at the link - TUTORIAL: JUNIT #RULE. With this, you will be very clear which spring xml file locations are provided.

Spring's Javaconfig and Prototyped Beans

I've moved my code from Spring's XML configuration to Java Configuration. I have everything working, but I have a question about how I implemented prototype beans - mainly, while what I'm doing works, is it the best way to do this? Somehow it just feels off!
I wrote the bean class this way:
#Component
#Scope("prototype")
public class ProtoBean {
...
}
Then to use the bean - this is the part that I'm just not sure about, although it does work:
#Component
public class BeanUser implements ApplicationContextAware {
ApplicationContext context;
#Override
public void setApplicationContext(ApplicationContext context)throws BeansException
{
this.context = context;
}
public void getProtoBean() {
ProtoBean protoBean = context.getBean(ProtoBean.class);
}
}
This gets me a prototyped bean, and in unit tests I just mocked the context, called setApplicationContext with the mock, and had the getBean call of the mock return a mock ProtoBean. So all is well.
I did this in the XML by using a factory, but that didn't seem to work too well, so this is where I ended up. But is there a way to do this without the context? Or just a better way?
Thanks!

I don't think is so much an issue of Spring XML vs Java-base configuration, but one of matching dependency scopes. Since Spring can only do dependency injection on the singleton-scoped bean at creation time, you have to lookup the prototype-scoped bean on demand. Of course the current bean-lookup approach works, but creates a dependency on the ApplicationContext. I can suggest a few other possibilities but the root of the issue is really what is involved in producing a ProtoBean, and what trade-offs should you accept.
You could make BeanUser itself prototype-scoped, which would allow you to wire in the ProtoBean as a member. Of course the trade-off is you now have the same problem on the clients of BeanUser, but sometimes that would not be a problem.
Another path could be using something like a singleton-scoped ProtoBeanFactory to provide ProtoBean instances, and hiding dependency lookups within the ProtoBeanFactory.
Finally, you could use a scoped-proxy bean to effectively hide the factory. It uses AOP to do this, and isn't always clear to others what sort of voodoo you have going. With XML you'd use <aop:scoped-proxy/> on the bean declaration. For annotations you'd use:
#Scope(proxyMode = ScopedProxyMode.TARGET_CLASS, value = "prototype")

Spring session-scoped beans (controllers) and references to services, in terms of serialization

a standard case - you have a controller (#Controller) with #Scope("session").
classes put in the session usually are expected to implement Serializable so that they can be stored physically in case the server is restarted, for example
If the controller implements Serializable, this means all services (other spring beans) it is referring will also be serialized. They are often proxies, with references to transaction mangers, entity manager factories, etc.
It is not unlikely that some service, or even controller, hold a reference to the ApplicationContext, by implementing ApplicationContextAware, so this can effectively mean that the whole context is serialized. And given that it holds many connections - i.e. things that are not serializable by idea, it will be restored in corrupt state.
So far I've mostly ignored these issues. Recently I thought of declaring all my spring dependencies transient and getting them back in readResolve() by the static utility classes WebApplicationContextUtils and such that hold the request/ServletContext in a ThreadLocal. This is tedious, but it guarantees that, when the object is deserialized, its dependencies will be "up to date" with the current application context.
Is there any accepted practice for this, or any guidelines for serializing parts of the spring context.
Note that in JSF, managed beans (~controllers) are stateful (unlike action-based web frameworks). So perhaps my question stands more for JSF, than for spring-mvc.

In this presentation (around 1:14) the speaker says that this issue is resolved in spring 3.0 by providing a proxy of non-serializable beans, which obtains an instance from the current application context (on deserialization)

It appears that bounty didn't attract a single answer, so I'll document my limited understanding:
#Configuration
public class SpringConfig {
#Bean
#Scope(proxyMode = ScopedProxyMode.TARGET_CLASS)
MyService myService() {
return new MyService();
}
#Bean
#Scope("request")
public IndexBean indexBean() {
return new IndexBean();
}
#Bean
#Scope("request")
public DetailBean detailBean() {
return new DetailBean();
}
}
public class IndexBean implements Serializable {
#Inject MyService myService;
public void doSomething() {
myService.sayHello();
}
}
public class MyService {
public void sayHello() {
System.out.println("Hello World!");
}
}
Spring will then not inject the naked MyService into IndexBean, but a serializable proxy to it. (I tested that, and it worked).
However, the spring documentation writes:
You do not need to use the <aop:scoped-proxy/> in conjunction with beans that are scoped as singletons or prototypes. If you try to create a scoped proxy for a singleton bean, the BeanCreationException is raised.
At least when using java based configuration, the bean and its proxy can be instantiated just fine, i.e. no Exception is thrown. However, it looks like using scoped proxies to achieve serializability is not the intended use of such proxies. As such I fear Spring might fix that "bug" and prevent the creation of scoped proxies through Java based configuration, too.
Also, there is a limitation: The class name of the proxy is different after restart of the web application (because the class name of the proxy is based on the hashcode of the advice used to construct it, which in turn depends on the hashCode of an interceptor's class object. Class.hashCode does not override Object.hashCode, which is not stable across restarts). Therefore the serialized sessions can not be used by other VMs or across restarts.

I would expect to scope controllers as 'singleton', i.e. once per application, rather than in the session.
Session-scoping is typically used more for storing per-user information or per-user features.
Normally I just store the 'user' object in the session, and maybe some beans used for authentication or such. That's it.
Take a look at the spring docs for configuring some user data in session scope, using an aop proxy:
http://static.springsource.org/spring/docs/2.5.x/reference/beans.html#beans-factory-scopes-other-injection
Hope that helps

I recently combined JSF with Spring. I use RichFaces and the #KeepAlive feature, which serializes the JSF bean backing the page. There are two ways I have gotten this to work.
1) Use #Component("session") on the JSF backing bean
2) Get the bean from ELContext when ever you need it, something like this:
#SuppressWarnings("unchecked")
public static <T> T getBean(String beanName) {
return (T) FacesContext.getCurrentInstance().getApplication().getELResolver().getValue(FacesContext.getCurrentInstance().getELContext(), null, beanName);
}

After trying all the different alternatives suggested all I had to do was add aop:scoped-proxy to my bean definition and it started working.
<bean id="securityService"
class="xxx.customer.engagement.service.impl.SecurityContextServiceImpl">
<aop:scoped-proxy/>
<property name="identityService" ref="identityService" />
</bean>
securityService is injected into my managedbean which is view scoped. This seems to work fine. According to spring documentation this is supposed to throw a BeanCreationException since securityService is a singleton. However this does not seems to happen and it works fine. Not sure whether this is a bug or what the side effects would be.

Serialization of Dynamic-Proxies works well, even between different JVMs, eg. as used for Session-Replication.
#Configuration public class SpringConfig {
#Bean
#Scope(proxyMode = ScopedProxyMode.INTERFACES)
MyService myService() {
return new MyService();
}
.....
You just have to set the id of the ApplicationContext before the context is refreshed (see: org.springframework.beans.factory.support.DefaultListableBeanFactory.setSerializationId(String))
AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext();
// all other initialisation part ...
// before! refresh
ctx.setId("portal-lasg-appCtx-id");
// now refresh ..
ctx.refresh();
ctx.start();
Works fine on Spring-Version: 4.1.2.RELEASE

Spring JSON View: ApplicationObjectSupport does not run in an ApplicationContext

I'm trying to use a Json View for Spring (http://spring-json.sourceforge.net/) (org.springframework.web.servlet.view.json.JsonView) but whenever I write a controller class that extends AbstractController I get the following Error:
java.lang.IllegalStateException: ApplicationObjectSupport instance [org.springframework.web.servlet.view.json.JsonView] does not run in an ApplicationContext
The weird thing is, that when I implement the Controller interface directly and do not inherit, it is fine. The error only happens when I inherit from AbstractController.
In my current case though I would like to extend AbstractFormController and hence can't write a class that does not inherit from AbstractController.
Any ideas?

That's a rather misleading error message, it's actually complaining that the JsonView is not running inside an app context. What it means is that the JsonView bean was not instantiated by Spring, but that you instantiated it yourself (JsonView extends ApplicationObjectSupport, and should therefore be Spring-managed).
However, you haven't given us any of your code, so it's hard to tell for sure. I'm guessing your controller is instantiating JsonView itself? You need to let Spring do that, either by injecting a JsonView bean into the controller, or perhaps using a ViewResolver (if Spring-Json supplies one).

If you are doing Java configuration ( as opposed to XML ), in your configuration class you may want to call setApplicationContext method on object that is complaining.
This is what did the trick for me in Spring MVC 3.2.2 when trying to initialize ContentNegotiatingViewResolver in Java.
Here is the sample configuration class:
#Configuration
#EnableWebMvc
...
public class MyConfig
{
#Inject
private ApplicationContext appContext;
#Bean
public ContentNegotiatingViewResolver contentNegotiatingViewResolver ( )
{
ContentNegotiatingViewResolver retVal =
new ContentNegotiatingViewResolver( );
...
retVal.setApplicationContext( appContext );
return retVal;
}
}

Injecting beans into a class outside the Spring managed context

I'm an end-user of one of my company's products. It is not very suitable for integration into Spring, however I am able to get a handle on the context and retrieve the required bean by name. However, I would still like to know if it was possible to inject a bean into this class, even though the class is not managed by Spring itself.
Clarification: The same application which is managing the lifecycle of some class MyClass, is also managing the lifecycle of the Spring context. Spring does not have any knowledge of the instance of MyClass, and I would like to some how provide the instance to the context, but cannot create the instance in the context itself.

You can do this:
ApplicationContext ctx = ...
YourClass someBeanNotCreatedBySpring = ...
ctx.getAutowireCapableBeanFactory().autowireBeanProperties(
someBeanNotCreatedBySpring,
AutowireCapableBeanFactory.AUTOWIRE_AUTODETECT, true);
You can use #Autowired and so on within YourClass to specify fields to be injected etc.

One way to bring a bean into Spring despite its manufacture being external is to use a helper class marked as a #Configuration bean that has a method (marked with #Bean) that actually makes the instance and hands it back through Spring (which does its property injection and proxy generation at that point).
I'm not quite sure what scope you need; with prototype, you'll get a fresh bean in each place.
#Configuration
public class FooBarMaker {
#Bean(autowire = Autowire.BY_TYPE)
#Scope("prototype")
public FooBar makeAFooBar() {
// You probably need to do some more work in here, I imagine
return new FooBar();
}
}
You can inject properties required for manufacture into the #Configuration bean. (I use this to create instances of an interface where the name of the class to instantiate is defined at runtime.)

suppose that u have the following dependency chain:
A --> B --> C --> x --> y -- > Z
A, B, C are spring managed beans (constructed and manged by spring framework)
x, y are really simple POJOs that constructed by your application, without spring assistance
now if you want that y will get a reference to Z using spring that you need to have a 'handle' to the spring ApplicationContext
one way to do it is to implement ApplicationContextAware interface . In this case I would suggest that either A, B or C will implement this interface and will store the applicationContext reference in a static member.
so lets take Class C for example:
class C implmenets ApplicationContextAware{
public static ApplicationContex ac;
void setApplicationContext(ApplicationContext applicationContext) {
ac = applicationContext;
}
.............
}
now, in class y you should have:
(Z)(C.ac.getBean("classZ")).doSomething()
HTH -- Yonatan

Another way to do this is to us use AspectJ. This is the recommended way of injection Spring beans into non-managed objects that are created with the new operator. See this for details:
http://www.javacodegeeks.com/2011/02/domain-driven-design-spring-aspectj.html

Searching endless combos of autowire inject spring bean into pojo applicationcontextaware beanaware etc circled me back here but this didnt provide a complete enough solution for me.
This is a much better implementation/tutorial of this IMO:
I hope it helps everyone like it finally helped me.
Accessing Spring Beans from outside Spring Context

Be careful that in oldest version of Spring, there is thread-safe problem with bean factory http://jira.springframework.org/browse/SPR-4672

If you want to create an object outside the Spring context, and make that object available for injection into other beans that are in the Spring context, you can follow the steps in this article.
Basically, you create a parent application context and push your external object into this parent context as a singleton. Then you create you main application context (for example, from xml files), with the parent application context as its parent.
Object externalObject = ...
GenericApplicationContext parent = new StaticApplicationContext();
parent.getBeanFactory().registerSingleton( "externalObject", externalObject );
parent.refresh();
ApplicationContext appContext = new ClassPathXmlApplicationContext( ... , parent);

From a Spring configuration class, set a static field on the non-Spring class that needs the beans.
I have an example in my answer to a Liquibase question: https://stackoverflow.com/a/71191546/5499391