Injecting JSF bean into Spring bean - impossible? - spring

I have a JSF 2.0 bean:
#ManagedBean
#SessionScoped
public class LoginBean implements Serializable
{
protected String name;
public String getName()
{
return name;
}
//....
}
I have a Spring 3.0 bean:
#Repository
public class Logins
{
#ManagedProperty(value="#{loginBean}")
protected LoginBean loginBean;
public void recordLogin()
{
//... record in db that loginBean.getName() just logged in
}
}
This code doesn't work, Logins.loginBean is never set.
Alternatively (its the same question, simplified) - would the following code ever work?
#Repository
public class SpringBean
{
#ManagedProperty(value="#{session.id}")
protected String id;
//....
}
The ContextLoaderListener and RequestLoaderListener are declared in web.xml.
Is it possible at all to inject a JSF bean into a Spring bean? (Without using yet another extra framework)
Or should I rather convert my JSF bean into a Spring bean and use the DelegatingVariableResolver trick in faces-config.xml? I have already tested this with a test Spring bean, and it works.

Using JSF annotations in spring-managed beans doesn't work. And it shouldn't - you should not inject things from the web layer in the other layers. It should be the other way around - inject spring services (or repositories) into web components (jsf managed beans), and invoke methods on them, passing the managed bean properties as arguments

Related

Error on injecting service: UnsatisfiedDependencyException: There was no object available for injection at SystemInjecteeImpl

I am trying to inject service in spring boot app. However I'm getting following error:
org.glassfish.hk2.api.UnsatisfiedDependencyException: There was no object available for injection at SystemInjecteeImpl(requiredType=RecommendationService,parent=RecommendationResourceImpl,qualifiers={},position=-1,optional=false,self=false,unqualified=null,1163111460)
Here is the code:
package com.example.test.recommendations.resources;
#Provider
public class RecommendationResourceImpl implements RecommendationResource {
#Inject
private RecommendationService recommendationService;
#Override
public List<Recommendation> get(String currency,
String entity) {
return recommendationService.getRecommendations(currency, entity));
}
}
Service interface
package com.example.test.recommendations.resources;
// imports
public interface RecommendationService {
List<Recommendation> getRecommendations(String currency, String entity);
Recommendation get(UUID uuid);
}
Service implementation
package com.example.test.recommendations.resources;
//imports
#Component
public class RecommendationServiceImpl implements RecommendationService{
#Override
public List<Recommendation> getRecommendations(String currency, String entity) {
return Collections.emptyList();
}
#Override
public Recommendation get(UUID uuid) {
return null;
}
}
What is correct way to inject services in spring boot applications?
I am using spring boot version 1.3.8 and Jersey version 2.25.1
From your stacktrace it is evident that the server cannot find the dependency bean to be injected.So initially check that the desired bean for the class is getting created during applciation start up.Verify that the service class is in the classpath for component scan to take place, otherwise include the package for scanning.
You are using the #Inject annotation instead of the spring #Autowired annotation to inject the beans.It will work fine but the first and most important difference between #Autowired and #Inject annotation is that the #Inject annotation is only available from Spring 3.0 onwards, so if you want to use annotation-driven dependency injection in Spring 2.5 then you have to use the #Autowired annotation.
Secondly, use the annotation #Service for the service layer rather than using the #Component annotation.
Indicates that an annotated class is a "Service", originally defined
by Domain-Driven Design (Evans, 2003) as "an operation offered as an
interface that stands alone in the model, with no encapsulated state."
May also indicate that a class is a "Business Service Facade" (in the
Core J2EE patterns sense), or something similar. This annotation is a
general-purpose stereotype and individual teams may narrow their
semantics and use as appropriate.
This annotation serves as a specialization of #Component, allowing for
implementation classes to be autodetected through classpath scanning.
#Service
public class RecommendationServiceImpl implements RecommendationService{
#Override
public List<Recommendation> getRecommendations(String currency, String entity) {
return Collections.emptyList();
}
#Override
public Recommendation get(UUID uuid) {
return null;
}
}
I am not an expert on using jersey with springboot , so i do not know if any configurations are causing this issue.
Maybe this thread might be of help to you more:
Dependency injection with Jersey 2.0
You probably never registered your Service with the DI-container. You can do that in your ResourceConfig, which you probably have since you are using jersey:
public class MyApplication extends ResourceConfig {
public MyApplication() {
register(new org.glassfish.hk2.utilities.binding.AbstractBinder() {
#Override
protected void configure() {
bind(RecommendationServiceImpl.class).to(RecommendationService.class).in(Singleton.class);
}
});
packages("com.example.test.recommendations.resources");
}
}
I am using hk2 without spring, so I usually annotate my interfaces with org.jvnet.hk2.annotations.Contract and the implementations with org.jvnet.hk2.annotations.Service. (note: not the spring #Service annotation), so I recommend trying that as well.

Spring Boot configuration for non-beans [duplicate]

This question already has answers here:
Injecting beans into a class outside the Spring managed context
(8 answers)
Closed 3 years ago.
Introduction
I have some business logic properties in the application.yml file.
They are loaded into the application via a #ConfigurationProperties annotated class.
How could I use these properties in a class which is not a Spring Bean? It cannot be a singleton, because many objects of it must be created during run-time.
Example
application.yml
business.foo: 2
BusinessProperties.java
#ConfigurationProperties("business")
#Getter // lombok
#Setter // lombok
public class BusinessProperties {
private int foo;
}
TypicalBean.java
#Component
public class TypicalBean {
private final BusinessProperties properties;
#Autowired
public TypicalBean(BusinessProperties properties) {
this.properties = properties;
}
#PostConstruct
public void printFoo() {
System.out.println("Foo: " + properties.getFoo()); // "Foo: 2"
}
}
NonBean.java
public class NonBean {
public void printFoo() {
System.out.println("Foo: ???"); // How to access the property?
}
}
Is there some way to create a non-singleton class, which can have access to configuration (or even other Spring beans) but otherwise works the same as a regular java class? Meaning that I can control its creation, it is collected by the garbage collector if not used anymore, etc.
You can still define the NonBean.class as a Component with Scope.Prototype
#Component
#Scope(value = BeanDefinition.SCOPE_PROTOTYPE)
public class NonBean {
#Autowired
public TypicalBean(BusinessProperties properties) {
this.properties = properties;
}
public void printFoo() {
System.out.println("Foo: " + properties.getFoo());
}
}
The trick is how you create an instance of NonBean.class. In the code where you'll be creating an instance of NonBean.class, use Spring's ObjectFactory<T>
private final ObjectFactory<NonBean> nonBeanFactory;
...
NonBean nonBean = nonBeanFactory.getObject();
The instantiated nonBean object will have been autowired.
All spring-beans creates by SpringApplicationContext. Bean - it's simple POJO-object, but created by Spring and saved in his container. If you want to get access to bean from outside of container - see this:
Getting Spring Application Context
Spring beans are really meant to be used within the application context but you might be able to achieve what you want by autowiring the properties to a static field in a Spring bean.
#Component
public class BusinessPropertiesUtils {
public static BusinessProperties INSTANCE;
#Autowired
public setBusinessProperties(BusinessProperties properties) {
this.INSTANCE = properties;
}
}
And then:
public class NonBean {
public void printFoo() {
System.out.println("Foo: " + BusinessPropertiesUtils.INSTANCE.getFoo());
}
}
PS: this is very hacky and definitely not the "Spring way".
You can configure beans with the prototype scope, which will give you a new instance of the bean every time it's requested.
From the Spring documentation:
In contrast to the other scopes, Spring does not manage the complete lifecycle of a prototype bean. The container instantiates, configures, and otherwise assembles a prototype object and hands it to the client, with no further record of that prototype instance.
...
In some respects, the Spring container’s role in regard to a prototype-scoped bean is a replacement for the Java new operator. All lifecycle management past that point must be handled by the client.
Example of how you can convert the TypicalBean class to a prototype scoped bean:
#Component
#Scope("prototype")
public class TypicalBean {
...
}
Another alternative is to manually instantiate the bean class (or any POJO) and injecting the dependencies (configuration, spring beans, etc.) through the constructor or setter methods, if you have them available or can get them from the Spring Context.
new TypicalBean(properties);

EJB injected to #Controller

I am trying to inject EJB into spring #Controller (spring boot), each time I receive null pointer on stetelessBean.tt();
#Local
public interface IStetelessBean {
void tt();
}
#Stateless
public class StetelesBean implements IStetelessBean {
public void tt(){
System.out.println("ttt");
}
}
#Controller
public class PersonService {
#EJB
IStetelessBean stetelessBean;
#RequestMapping("/test")
public void test(){
stetelessBean.tt();
}
}
Any idea? I am not sure what is wrong.
Spring can only inject beans, it knows about. By default, EJBs are not registered as Spring Beans. Also the #EJB annotation is not recognised by Spring. The only examples in the Spring documentation use XML configuration, so far i could not find any example for Java configuration. You might be better off with changing your EJB into a Spring component, if that's possible.

#Autowired service inside a #ManagedBean #Component class is null during JSF request [duplicate]

This question already has answers here:
Spring JSF integration: how to inject a Spring component/service in JSF managed bean?
(4 answers)
Closed 6 years ago.
I tried union Spring 3(MVC) with JSF 2. I have some experience in Spring and JSF, but never tried to join them before. In the end I have 2 files
#ManagedBean(name = "userBean")
#Scope
#Component
public class someBean {
#Autowired
private TestService testService;
public void printString() {
System.out.println(testService.getString());
}
}
and
#ManagedBean(name = "studentBean")
#Scope
#Component
public class StudentBean {
#Autowired
private TestService testService;
public void printString() {
System.out.println(testService.getString());
}
}
For these file I have right configuration for spring, jsf, and web.xml. And have .xhtml page where I start printString() for 'someBean' and for 'StudentBean'. I have the NPE in first case and 'some string' in the console in second case.
The reason is simple - different bean names in the Spring context and JSF. all problems finished after
#Component => #Component("userBean")
public class someBean {
In the debug I saw that
private TestService testService;
#Autowired
public void setTestService(TestService testservice) {
this.testService = testService;
}
When JSF bean is creating testService sets not null, but it is null during JSF lifecycle when
public void pringString() {
testService.blah();
}
testService is null. It is what I can't understand. Has someone deep knowledge the Spring and JSF to describe this situation in details?
Both JSF and Spring can act as bean containers. The #ManagedBean annotation instructs the JSF managed bean facility to create a new instance of the class, and manage it under the given name. The #Component annotation instructs the Spring ApplicationContext to create a new instance of the class, and manage it under the given name. That is, both JSF and Spring create an instance of that class, the JSF one is reachable through EL, but the Spring one gets its dependencies injected (because, being a spring annotation, #Autowired is not understood by the JSF managed bean facility).
So you have a choice: Use the JSF managed bean facility for everything (which I would not recommend, as it is rather limited), use CDI for everything (which is an option, but does not use Spring), or use Spring for everything (which I usually do), by removing the #ManagedBean annotation, and making Spring beans accessible through EL by registering a SpringBeanFacesELResolver in your faces-config.xml. The Spring reference manual describes this in section 19.3.1.
I had the same issue, it was due to the property name of #ManagedBean annotation.My backing bean looks like this
#Component
#ManagedBean(name="mainBean")
#SessionScoped
public class MainManagedBean{...}
As you can see, the name given to the bean (mainBean) is different to the default name (mainManagedBean) that the backing bean should have.
I have fixed the issue by setting the property name to "mainManagedBean". My bean becomes like this:
#Component
#ManagedBean(name="mainManagedBean")
#SessionScoped
public class MainManagedBean{...}
I wish this can help you
I believe the reason why testService is null is because testService has not been instantiated yet when managed bean is being constructed. So you can use #PostConstruct to inject Spring beans into a managed bean.
#ManagedBean(name = "userBean")
#Scope
#Component
public class someBean {
#Autowired
private TestService testService;
public void printString() {
System.out.println(testService.getString());
}
#PostConstruct
private void init() {
ExternalContext externalContext = FacesContext.getCurrentInstance().getExternalContext();
ServletContext servletContext = (ServletContext) externalContext.getContext();
WebApplicationContextUtils.getRequiredWebApplicationContext(servletContext).
getAutowireCapableBeanFactory().
autowireBean(this);
}
}
#Service
public class TestService {
......
}

Spring : autowiring inside non spring class

I have this HTTP listener subclass
public class MigificSessionListener implements HttpSessionListener {
#Autowired
#Qualifier("notificationThread")
private NotificationThread notificationThread;
#Override
public void sessionDestroyed(HttpSessionEvent hse) {
// here notificationThread value is null
}
}
Value of notificationThread inside sessionDestroyed() is null.
How can i autowire sessionDestroyed inside this class ?
Your MigificSessionListener in not in your spring conext, spring even do not know it exists.
You can use WebApplicationContextUtils to get your spring context from ServletContext
WebApplicationContextUtils.getWebApplicationContext(sessionEvent.getSession().getServletContext())
You can enable Spring AOP with #EnableSpringConfigured and annotate your class with #Configurable. This let spring manage instances which are created outside the spring context with new. You will also need to enable either load-time weaving or compile-time weaving. This is documented in 9.8.1 Using AspectJ to dependency inject domain objects with Spring.
#Configuration
#EnableSpringConfigured
public class AppConfig {
}
#Configurable
public class MigificSessionListener implements HttpSessionListener {
#Autowired
#Qualifier("notificationThread")
private NotificationThread notificationThread;
//...
}
Convert your non-Spring managed class MigificSessionListener into a Spring-managed one by annotating it with #Configurable.
For this annotation to be recognised you need <context:spring-configured/> in your Spring XML config or #EnableSpringConfigured if you are using Spring Java config.
The #Autowired or injection of other dependencies will then succeed.

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