Autowire constructor is called twice even using Qualifier in spring - java

I am trying to learn autowire with Qualifier in spring and the autowired class constructor is called twice .
I have the following class:
MainApp:
public class MainApp {
public static void main(String[] args) {
// ApplicationContext context = new ClassPathXmlApplicationContext("Beans.xml");
ApplicationContext ctx =
new AnnotationConfigApplicationContext(HelloWorldConfig.class);
// TextEditor obj = (TextEditor) ctx.getBean("helloWorld");
TextEditor obj = (TextEditor)ctx.getBean(TextEditor.class);
obj.spellCheck();
}
SpellChecker:
public class SpellChecker {
public SpellChecker() {
System.out.println("Inside SpellChecker constructor.");
}
public void checkSpelling() {
System.out.println("Inside checkSpelling.");
}
TextEditor
public class TextEditor {
#Qualifier("a")
#Autowired
private SpellChecker spellChecker;
public SpellChecker getSpellChecker( ) {
return spellChecker;
}
public void spellCheck() {
spellChecker.checkSpelling();
}
}
I have the java based configuration which has multiple bean with same Type and want to select a single bean with Qualifier but the output shows the constructor is called twice.\
HelloWorldConfig
#Component
public class HelloWorldConfig {
#Bean
public HelloWorld helloWorld(){
return new HelloWorld();
}
#Bean
public TextEditor textEditor(){
return new TextEditor();
}
#Bean(name="a")
public SpellChecker spellChecker(){
return new SpellChecker();
}
#Bean(name="b")
public SpellChecker spellChecker1(){
return new SpellChecker();
}
}
OUTPUT:
Inside SpellChecker constructor.
Inside SpellChecker constructor.
Inside checkSpelling.
I was expecting a single SpellChecker constructor call since i used Qualifier("a") to specify the bean, however the constructor is called twice even if I used Qualifier to select a sinlge bean. Why is it called twice??

Check Out HelloWorldConfig file. You've declared 2 beans of type SpellChecker:
#Bean(name="a")
public SpellChecker spellChecker(){
return new SpellChecker();
}
#Bean(name="b")
public SpellChecker spellChecker1(){
return new SpellChecker();
}
Both beans are created by spring, although only one bean is injected into the TextEditor.
In spring its perfectly fine to have more than one bean of the same type or beans that implement the same interface (think about listeners - there can be many of them) - so spring container will create them all during the application start.
If you want to inject one of those beans however into another bean (like TextEditor in your case), spring won't have a clue which one to inject, that's why you they've added a "qualifier" feature.
Another note, you've by mistake put a #Component annotation on the configuration class, instead you should use #Configuration annotation to specify that this class contains a series of beans definitions (that you indeed declare with #Bean annotation). Although the "configuration" is also a component (managed by spring) - spring still treats it in a significantly different way than regular beans.
And yet another note: although its not directly related to your question, it seems like you're mixing 2 styles of configurations in the code snippet you've provided: the style with #Qualifier/#Autowired (this way was added in spring 2.5 if I'm not mistaken) and the style of java configurations: #Configuration class with #Bean-s in it.
You can avoid using autowire altogether and inject the dependencies via constructor called from java config like this:
#Configuration
public class HelloWorldConfig {
#Bean
public HelloWorld helloWorld(){
return new HelloWorld();
}
#Bean
public TextEditor textEditor(#Qualifier("a") SpellChecker spellChecker){ // note the dependency here
return new TextEditor(spellChecker);
}
#Bean(name="a")
public SpellChecker spellChecker(){
return new SpellChecker();
}
#Bean(name="b")
public SpellChecker spellChecker1(){
return new SpellChecker();
}
}
// the TextEditor Class should have a constructor with one argument:
public class TextEditor {
private final SpellChecker spellChecker;
public TextEditor(SpellChecker spellChecker) {
this.spellChecker = spellChecker;
}
...
}
// or if you use lombok library:
#AllArgsConstructor
public class TextEditor {
private final SpellChecker spellChecker;
...
}
Now note, that your "business classes" are not even aware of spring all the "resolution" (usage of qualifier and injection rules) is done in spring configuration which is a special class anyway.

Related

Spring: Mixing of wiring in JavaConfig with wiring using #Autowired

I am totally confused about mixing of "wiring in JavaConfig" and "wiring using #Autowired". I will tell you my problems in 4 scenarios:
(I am ok with mixing of #Autowired and stereotype annotations and I don't have any question about that. my problem is Javaconfig and #autowired)
Scenario 1:
My CDPlayer Class:
public class CDPlayer implements MediaPlayer {
private CompactDisc cd;
public CDPlayer() {
cd = new CompactDisc() {
#Override
public void play() {
System.out.println("123456");
}
};
}
#Autowired
public CDPlayer(CompactDisc cd) {
this.cd = cd;
}
public void play() {
cd.play();
}
}
My JavaConfig File:
#Configuration
public class CDPlayerConfig {
#Bean
public CompactDisc sgtPeppers() {
return new SgtPeppers();
}
#Bean
public CDPlayer cdPlayer(CompactDisc compactDisc) {
return new CDPlayer();
}
}
For Example in this scenario, I see that #Autowired is effectless and cannot make Spring to invoke and use the parameterized constructor and no-arg constructor will be executed (because it is invoked in the #Bean method) and the output is the text "123456".
=================================================================
SCENARIO 2:
My JavaConfig File:
#Configuration
public class CDPlayerConfig {
#Bean
public CompactDisc sgtPeppers() {
return new SgtPeppers();
}
#Bean
public CDPlayer cdPlayer(CompactDisc compactDisc) {
return new CDPlayer(compactDisc);
}
}
My CDPlayer Class:
public class CDPlayer implements MediaPlayer {
private CompactDisc cd;
public CDPlayer(CompactDisc cd) {
this.cd = cd;
}
public void play() {
cd.play();
}
}
we wired those two beans in the config file. and I know that we do not need #Autowired at all.
=================================================================
SCENARIO 3:
My JavaConfig File:
#Configuration
public class CDPlayerConfig {
#Bean()
public CompactDisc sgtPeppers() {
return new SgtPeppers();
}
#Bean
public CDPlayer cdPlayer() {
return new CDPlayer();
}
}
My CDPlayer Class:
public class CDPlayer implements MediaPlayer {
private CompactDisc cd;
public CDPlayer(CompactDisc cd) {
this.cd = cd;
}
public void play() {
cd.play();
}
#Autowired
public void setCd(CompactDisc cd) {
this.cd = cd;
}
}
I know that if #Autowired is above of parameterized constructor, that constructor will not be executed but now that is above of setCd(), this method will be executed.
=================================================================
SCENARIO 4:
My JavaConfig File:
#Configuration
public class CDPlayerConfig {
#Bean
public CompactDisc sgtPeppers() {
return new SgtPeppers();
}
#Bean
public CDPlayer cdPlayer(CompactDisc compactDisc) {
return new CDPlayer(compactDisc);
}
}
My CDPlayer Class:
public class CDPlayer implements MediaPlayer {
private CompactDisc cd;
public CDPlayer() {
}
public CDPlayer(CompactDisc cd) {
this.cd = cd;
}
public void play() {
cd.play();
}
#Autowired
public void doSomething(CompactDisc cd) {
this.cd = new CompactDisc() {
#Override
public void play() {
System.out.println("AAAAA");
}
};
}
}
and in this scenario, Although that we wired those two beans together, but #Autowired makes spring to execute the doSomething()method.
What is happening?! I can't see the Big Picture. I can't understand the pattern that is going on.
sometimes #Autowired works and sometimes doesn't work. what is the general pattern? do we need #Autowired at all when we wire beans together in JavaConfig file?
An autowired constructor is invoked if spring invokes the constructor by reflection, typically because you declare the bean using component scanning or XML config. If you manually invoke a constructor in a #Bean method, that constructor executes, and #Autowired has no effect.
An autowired method is invoked after the bean has been created, irrespective of how the bean was created.
The reason is that, in Java, each constructor call creates a new object, making it impossible to call two constructors for the same object. That's why Spring can't call a second constructor if you have already called a different one. In contrast, it is possible to call many methods on the same object, so Spring does support method autowiring just fine.
To conclude, you can use autowiring with JavaConfig, but you should autowire fields or methods rather than constructors. Or you can do without autowiring, and pass everything explicitly in your #Bean method. Or any mixture of the two.
The Spring Context contains all the beans you need in your program, and Spring do the rest of the job for you. But something to understand is that your beans comes from many parts of your application :
Internal beans (POJO from your domain).
External beans (POJO from other libraries or third partie classes).
Reading this from the spring documentation, you can find all the differents sources of beans :
#SpringBootApplication is a convenience annotation that adds all of
the following:
#Configuration: Tags the class as a source of bean definitions for the
application context.
#EnableAutoConfiguration: Tells Spring Boot to start adding beans
based on classpath settings, other beans, and various property
settings. For example, if spring-webmvc is on the classpath, this
annotation flags the application as a web application and activates
key behaviors, such as setting up a DispatcherServlet.
#ComponentScan: Tells Spring to look for other components,
configurations, and services in the com/example package, letting it
find the controllers.
Follow these rules :
In your domain classes (Controller, Service) : use #Autowired in your constructor. It is the recommanded way to inject your dependencies.
You want to use external classes : implements a Java Configuration with #Configuration annotation, to instanciate your external classes as beans.
You want to create custom utilities classes : decorate it with #Component.
When you have more than on implementation, use #Qualifier and define your beans in a #Configuration class.

Spring DI having two constructors at the same time

This is an anti pattern, but I am curious what will actually happen.
If you explicitly define a no-args constructor and a constructor with an autowired parameter, how exactly will spring framework initialize it?
#Service
class Clazz {
private MyBean myBean;
public Clazz(){}
#Autowired
public Clazz(MyBean myBean){
this.myBean = myBean;
}
}
On top of above answers, if there is single constructor declared without #autowire, spring uses same constructor for injection.
If there multiple constructors, then Spring uses constructor which is #autowired.
Mentioned in Spring Doc https://docs.spring.io/spring/docs/4.3.x/spring-framework-reference/htmlsingle/#beans-autowired-annotation
As of Spring Framework 4.3, an #Autowired annotation on such a
constructor is no longer necessary if the target bean only defines one
constructor to begin with. However, if several constructors are
available, at least one must be annotated to teach the container which
one to use
The constructor marked by #Autowired will be used by spring. You can validate this by running the following code.
public class Main {
#Component
static class MyBean {}
#Service
static class Clazz {
private MyBean myBean;
public Clazz(){
System.out.println("empty");
}
#Autowired
public Clazz(MyBean myBean){
this.myBean = myBean;
System.out.println("non-empty");
}
}
#Component
#ComponentScan("my.package")
private static class Configuration {
}
public static void main(String[] args) {
var ctx = new AnnotationConfigApplicationContext();
ctx.register(Configuration.class);
ctx.refresh();
ctx.getBean(Clazz.class);
}
}
The code prints non-empty.
Spring choose constructor first by the largest number of parameters
sortConstructors consider preferring public constructors and ones with a maximum number of arguments.
Meaning Clazz(MyBean myBean)
This is the Comparator used:
(e1, e2) -> {
int result = Boolean.compare(Modifier.isPublic(e2.getModifiers()), Modifier.isPublic(e1.getModifiers()));
return result != 0 ? result : Integer.compare(e2.getParameterCount(), e1.getParameterCount());

How can I start a Main-Class in Spring-Boot?

I want to execute a very simple example which explains the IoC-concept in Spring-Boot.
For that I have create a Bean which gets #Autowired to a main-class, which has a method which does something with the bean.
The bean:
The main:
#Component
public class MyMain {
#Autowired
private MyBean bean1;
public void usingTheBean()
{
bean1.setName("Thats my first bean!");
bean1.setAttribute("And thats just an attribute");
System.out.println(bean1);
}
public static void main(String[] args) {
//MyMain main = new MyMain();
//main.usingTheBean();
}
}
My SpringBootApplication:
#SpringBootApplication
public class DemoApplication {
public static void main(String[] args) {
SpringApplication.run(DemoApplication.class, args);
MyMain main = new MyMain();
main.usingTheBean();
}
}
How can I start the Main-class? with out getting the
java.lang.NullPointerException
for the #Autowired Bean "MyBean" in the main?
I know that the reason for the NullPointer-Exception is that I created the Main-class with the "new" keyword.
But the question focuses more on the question "How can I start a main-class with spring-boot"
Usually, you do not want to use the context directly to create a bean yourself. You should just let the context initialize and then just use the autowired beans. Most likely, the way you approach this problem is very different from the Spring-way of achieving it.
You should have a look at the following examples:
using the CommandLineRunner interface (see here) or
using the InitializingBean interface (see here)
Alternatively, you can solve this via configuration:
#Configuration
public class MyConfig {
#Bean
public MyBean myBean() {
MyBean bean = new MyBean();
bean.setName("...");
bean.setAttribute("...");
return bean;
}
}
You can then simply use
#Autowired
MyBean myBean;
to autowire it.
Yet another alternative would be to inject the values from a config file (e.g. application.properties) if this is possible in your case:
#Component
public class MyBean {
#Value("${my.config.value}")
private String name;
#Value("${my.config.attribute}")
private String attribute;
public MyBean(){
}
...
Having the following entries in your application.properties:
my.config.value = Some value content
my.config.attribute = Some attribute content

Changing a class annotated #Component to #Bean annotated method

I have a class that is annotated #Component that was then #Autowired into another class. However, I need to remove this #Component annotation and instead, create it with an #Bean annotated method in the class where its was previously autowired.
Where previously the classes looked like:
#Component
public class MyClass implements IMyClass
{
// Stuff
}
#Configuration
public class MyUsingClass
{
#Autowired
private IMyClass myClass;
private void methodUsingMyClass()
{
myClass.doStuff();
}
}
So now I have removed the #Component annotation and written a #Bean annotated method like this:
public class MyClass implements IMyClass
{
// Stuff
}
#Configuration
public class MyUsingClass
{
#Bean
public IMyClass getMyClass()
{
return new MyClass();
}
....
}
My question is around replacing the previous call of myClass.doStuff() to use the new bean. Do I now pass in a parameter of type MyClass to the private method:
private void methodUsingMyClass(final MyClass myClass)
{
myClass.doStuff();
}
... or do I call this method directly (doesn't seem the correct way to me):
private void methodUsingMyClass()
{
getMyClass().doStuff();
}
... or are neither of these correct?
I think you misunderstand the #Bean annotation. It can be used to create a Bean. So basically spring will scan all classes, will find your #Bean and create a Bean, not more. You can now use this bean, like if you would use one created with <bean></bean>. To actually use the bean you need to either get it from ApplicationContext or #Autowire it. Of course you can still use that function like any other function in your code, to create a new instance of that object, but that would contradict to what you want to achieve with beans
Using Annotations that solutions
public class MyClass implements IMyClass{
private OtherClassInjection otherClassInjection;
private OtherClassInjection2 otherClassInjection2;
MyClass(OtherClassInjection otherClassInjection, OtherClassInjection2 otherClassInjection2){
this.otherClassInjection=otherClassInjection;
this.otherClassInjection2=otherClassInjection2;
}
public void useObject(){
otherClassInjection.user();
}
}
#Bean(name = "myClass")
#Autowired
#Scope("prototype") //Define scope as needed
public MyClass getMyClass(#Qualifier("otherClassInjection") OtherClassInjection otherClassInjection,
OtherClassInjection2 otherClassInjection2) throws Exception
{
return new MyClass(otherClassInjection, otherClassInjection2);
}
that logical, it's work injection #Autowired when create a Bean if context are know that bean, that you will to want inject.
I'm use that way.

How to instantiate Spring managed beans at runtime?

I stuck with a simple refactoring from plain Java to Spring. Application has a "Container" object which instantiates its parts at runtime. Let me explain with the code:
public class Container {
private List<RuntimeBean> runtimeBeans = new ArrayList<RuntimeBean>();
public void load() {
// repeated several times depending on external data/environment
RuntimeBean beanRuntime = createRuntimeBean();
runtimeBeans.add(beanRuntime);
}
public RuntimeBean createRuntimeBean() {
// should create bean which internally can have some
// spring annotations or in other words
// should be managed by spring
}
}
Basically, during load container asks some external system to provide him information about number and configuration of each RuntimeBean and then it create beans according to given spec.
The problem is: usually when we do in Spring
ApplicationContext context = new AnnotationConfigApplicationContext(ApplicationConfiguration.class);
Container container = (Container) context.getBean("container");
our object is fully configured and have all dependencies injected. But in my case I have to instantiate some objects which also needs dependency injection after I execute load() method.
How can I achieve that?
I am using a Java-based config. I already tried making a factory for RuntimeBeans:
public class BeanRuntimeFactory {
#Bean
public RuntimeBean createRuntimeBean() {
return new RuntimeBean();
}
}
Expecting #Bean to work in so called 'lite' mode. http://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/context/annotation/Bean.html Unfortunately, I found no difference with simply doing new RuntimeBean();
Here is a post with a similar issue: How to get beans created by FactoryBean spring managed?
There is also http://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/beans/factory/annotation/Configurable.html but it looks like a hammer in my case.
I also tried ApplicationContext.getBean("runtimeBean", args) where runtimeBean has a "Prototype" scope, but getBean is an awful solution.
Update 1
To be more concrete I am trying to refactor this class:
https://github.com/apache/lucene-solr/blob/trunk/solr/core/src/java/org/apache/solr/core/CoreContainer.java
#see #load() method and find "return create(cd, false);"
Update 2
I found quite interesting thing called "lookup method injection" in spring documentation:
http://docs.spring.io/spring/docs/current/spring-framework-reference/html/beans.html#beans-factory-lookup-method-injection
And also an interesting jira ticket https://jira.spring.io/browse/SPR-5192 where Phil Webb says https://jira.spring.io/browse/SPR-5192?focusedCommentId=86051&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-86051 that javax.inject.Provider should be used here (it reminds me Guice).
Update 3
There is also http://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/beans/factory/config/ServiceLocatorFactoryBean.html
Update 4
The issue with all these 'lookup' methods is they don't support passing any arguments.. I also need to pass arguments as I would do with applicationContext.getBean("runtimeBean", arg1, arg2). Looks like it was fixed at some point with https://jira.spring.io/browse/SPR-7431
Update 5
Google Guice have a neat feature for it called AssistedInject. https://github.com/google/guice/wiki/AssistedInject
Looks like I found a solution. As I am using java based configuration it is even simpler than you can imagine. Alternative way in xml would be lookup-method, however only from spring version 4.1.X as it supports passing arguments to the method.
Here is a complete working example:
public class Container {
private List<RuntimeBean> runtimeBeans = new ArrayList<RuntimeBean>();
private RuntimeBeanFactory runtimeBeanFactory;
public void load() {
// repeated several times depending on external data/environment
runtimeBeans.add(createRuntimeBean("Some external info1"));
runtimeBeans.add(createRuntimeBean("Some external info2"));
}
public RuntimeBean createRuntimeBean(String info) {
// should create bean which internally can have some
// spring annotations or in other words
// should be managed by spring
return runtimeBeanFactory.createRuntimeBean(info);
}
public void setRuntimeBeanFactory(RuntimeBeanFactory runtimeBeanFactory) {
this.runtimeBeanFactory = runtimeBeanFactory;
}
}
public interface RuntimeBeanFactory {
RuntimeBean createRuntimeBean(String info);
}
//and finally
#Configuration
public class ApplicationConfiguration {
#Bean
Container container() {
Container container = new Container(beanToInject());
container.setBeanRuntimeFactory(runtimeBeanFactory());
return container;
}
// LOOK HOW IT IS SIMPLE IN THE JAVA CONFIGURATION
#Bean
public BeanRuntimeFactory runtimeBeanFactory() {
return new BeanRuntimeFactory() {
public RuntimeBean createRuntimeBean(String beanName) {
return runtimeBean(beanName);
}
};
}
#Bean
#Scope(ConfigurableBeanFactory.SCOPE_PROTOTYPE)
RuntimeBean runtimeBean(String beanName) {
return new RuntimeBean(beanName);
}
}
class RuntimeBean {
#Autowired
Container container;
}
That's it.
Thanks everyone.
i think that your concept is wrong by using
RuntimeBean beanRuntime = createRuntimeBean();
you are bypassing Spring container and resorting to using regular java constructor therefore any annotations on factory method are ignored and this bean is never managed by Spring
here is the solution to create multiple prototype beans in one method, not pretty looking but should work, I autowired container in RuntimeBean as proof of autowiring shown in log also you can see in log that every bean is new instance of prototype when you run this .
'
#Configuration
#ComponentScan
#EnableAutoConfiguration
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
ApplicationContext context = new AnnotationConfigApplicationContext(Application.class);
Container container = (Container) context.getBean("container");
container.load();
}
}
#Component
class Container {
private List<RuntimeBean> runtimeBeans = new ArrayList<RuntimeBean>();
#Autowired
ApplicationContext context;
#Autowired
private ObjectFactory<RuntimeBean> myBeanFactory;
public void load() {
// repeated several times depending on external data/environment
for (int i = 0; i < 10; i++) {
// **************************************
// COMENTED OUT THE WRONG STUFFF
// RuntimeBean beanRuntime = context.getBean(RuntimeBean.class);
// createRuntimeBean();
//
// **************************************
RuntimeBean beanRuntime = myBeanFactory.getObject();
runtimeBeans.add(beanRuntime);
System.out.println(beanRuntime + " " + beanRuntime.container);
}
}
#Bean
#Scope(BeanDefinition.SCOPE_PROTOTYPE)
public RuntimeBean createRuntimeBean() {
return new RuntimeBean();
}
}
// #Component
class RuntimeBean {
#Autowired
Container container;
} '
A simple approach:
#Component
public class RuntimeBeanBuilder {
#Autowired
private ApplicationContext applicationContext;
public MyObject load(String beanName, MyObject myObject) {
ConfigurableApplicationContext configContext = (ConfigurableApplicationContext) applicationContext;
SingletonBeanRegistry beanRegistry = configContext.getBeanFactory();
if (beanRegistry.containsSingleton(beanName)) {
return beanRegistry.getSingleton(beanName);
} else {
beanRegistry.registerSingleton(beanName, myObject);
return beanRegistry.getSingleton(beanName);
}
}
}
#Service
public MyService{
//inject your builder and create or load beans
#Autowired
private RuntimeBeanBuilder builder;
//do something
}
Instead of using SingletonBeanRegistry you can use this:
BeanFactory beanFactory = configContext.getBeanFactory();
Anyway SingletonBeanBuilder extends HierarchicalBeanFactory and HierarchicalBeanFactory extends BeanFactory
You don't need the Container because all of the runtime objects should be created, held and managed by ApplicationContext. Think about a web application, they are much the same. Each request contains external data/environment info as you mentioned above. What you need is a prototype/request scoped bean like ExternalData or EnvironmentInfo which can read and hold runtime data through a static way, let's say a static factory method.
<bean id="externalData" class="ExternalData"
factory-method="read" scope="prototype"></bean>
<bean id="environmentInfo" class="EnvironmentInfo"
factory-method="read" scope="prototype/singleton"></bean>
<bean class="RuntimeBean" scope="prototype">
<property name="externalData" ref="externalData">
<property name="environmentInfo" ref="environmentInfo">
</bean>
If you do need a container to save the runtime objects, code should be
class Container {
List list;
ApplicationContext context;//injected by spring if Container is not a prototype bean
public void load() {// no loop inside, each time call load() will load a runtime object
RuntimeBean bean = context.getBean(RuntimeBean.class); // see official doc
list.add(bean);// do whatever
}
}
Official doc Singleton beans with prototype-bean dependencies.
It is possible to register beans dynamically by using BeanFactoryPostProcesor. Here you can do that while the application is booting (spring's application context has been initialized). You can not register beans latest, but on the other hand, you can make use of dependency injection for your beans, as they become "true" Spring beans.
public class DynamicBeansRegistar implements BeanFactoryPostProcessor {
#Override
public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
if (! (beanFactory instanceof BeanDefinitionRegistry)) {
throw new RuntimeException("BeanFactory is not instance of BeanDefinitionRegistry");
}
BeanDefinitionRegistry registry = (BeanDefinitionRegistry) beanFactory;
// here you can fire your logic to get definition for your beans at runtime and
// then register all beans you need (possibly inside a loop)
BeanDefinition dynamicBean = BeanDefinitionBuilder.
.rootBeanDefinition(TheClassOfYourDynamicBean.class) // here you define the class
.setScope(BeanDefinition.SCOPE_SINGLETON)
.addDependsOn("someOtherBean") // make sure all other needed beans are initialized
// you can set factory method, constructor args using other methods of this builder
.getBeanDefinition();
registry.registerBeanDefinition("your.bean.name", dynamicBean);
}
#Component
class SomeOtherClass {
// NOTE: it is possible to autowire the bean
#Autowired
private TheClassOfYourDynamicBean myDynamicBean;
}
As presented above, you can still utilize Spring's Dependency Injection, because the post processor works on the actual Application Context.

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