Inject String with qualifier in CDI - cdi

I'm trying to do simple thing. Inject qualified String (or File) in CDI.
So I have a qualifier:
#Retention(RetentionPolicy.RUNTIME)
#Target({FIELD,METHOD,PARAMETER,TYPE})
#Qualifier
public #interface FilesRepositoryPath {}
I have a producer:
public class FilesRepositoryPathProducer {
#Produces
#FilesRepositoryPath
public String getRepositoryDirectory() {
return "path.taken.from.configuration";
}
}
And I'm trying to use it:
#ApplicationScoped
public class FilesRepository {
#Inject
public FilesRepository(#FilesRepositoryPath String filesDirectory) {
//Do some stuff
}
}
However, WELD cannot instantiate this bean. I am getting an exception:
org.jboss.arquillian.impl.event.FiredEventException: org.jboss.weld.exceptions.UnproxyableResolutionException: WELD-001410 The injection point [field] #Inject private za.co.fnb.commercial.dms.file.FilesRepositoryBeanTest.repo has non-proxyable dependencies
I know String is unproxable, but why WELD wants to create a proxy? It has #Dependent scope, so AFAIK it shouldn't create proxy anyway. How can I make it work?

you need the default constructor
#ApplicationScoped
public class FilesRepository {
public FilesRepository() {
}
#Inject
public FilesRepository(#FilesRepositoryPath String filesDirectory) {
//Do some stuff
}
}

Related

CDI #Produces with multiple properties files

Thanks to this post, https://stackoverflow.com/a/28047512/1227941 I am now using CDI to make msg available in my #Named beans like this:
#RequestScoped
public class BundleProducer {
#Produces
public PropertyResourceBundle getBundle() {
FacesContext context = FacesContext.getCurrentInstance();
return context.getApplication().evaluateExpressionGet(context, "#{msg}", PropertyResourceBundle.class);
}
}
With Injection like:
#Inject
private PropertyResourceBundle bundle;
The question: What should I do if I have more property files: ui.properties, admin.properties ...?
I'd simply use a classifier annotation to choose which bundle to inject. Ripped from a little project of mine:
The annotation:
#Qualifier
#Target({ ElementType.TYPE, ElementType.METHOD, ElementType.FIELD, ElementType.PARAMETER })
#Retention(RetentionPolicy.RUNTIME)
public #interface Bundle {
#Nonbinding
public String value() default "";
}
The producer method (adapt as necessary for your context):
#Produces #Bundle ResourceBundle loadBundle(InjectionPoint ip) {
String bundleName = ip.getAnnotated().getAnnotation(Bundle.class).value();
ResourceBundle res = ResourceBundle.getBundle(bundleName);
return res;
}
And the injection:
#Inject #Bundle("ui")
private ResourceBundle uiResources;

Why EJB's constructor called twice in a #RequestScoped bean?

I have an EJB bean injected in a Managed Bean. Its constructor is called twice.
For example, I get:
com.logic.jsf.AdditionManagedBean created
com.logic.Addition$$$view45 created
com.logic.Addition created
I know #PostConstruct but I'm trying to understand why that happens. Is it because of proxy, and in that case shouldn't I see a proxy related literal in the printed name of the class?
#Stateless
#LocalBean
public class Addition{
public Addition(){
System.out.println(this.getClass().getName() +" created");
}
public String getAddition(){
return "Addition";
}
}
Injected in:
#ManagedBean
#RequestScoped
public class AdditionManagedBean {
#EJB
Addition addition;
public AdditionManagedBean(){
System.out.println(this.getClass().getName()+" created");
}
public String getAddition(){
return addition.getAddition();
}
}

Access Session Bean Property/Inject Session Bean

Still learning JSF and Java and having trouble understanding how to access a session bean property.
I have a LoggedUser session bean which sets the user that is logged in(using the login method).
#ManagedBean(name="loggedUser")
#Stateless
#LocalBean
#SessionScoped
public class LoggedUser {
#EJB
UserEJB userEJB;
#PersistenceContext
private EntityManager em;
private UserEntity loggedUser;
private String loginUserName;
private String loginPassword;
public LoggedUser() {}
public UserEntity getLoggedUser() {
return loggedUser;
}
public void setLoggedUser(UserEntity loggedUser) {
this.loggedUser = loggedUser;
}
public String authenticate() {
if (loggedUser == null) {
return "login.xhtml";
} else {
return "";
}
}
public String login() {
if (userEJB.validateLogin(loginUserName, loginPassword)) {
setLoggedUser(userEJB.fetchUser(loginUserName));
return "index.xhtml";
}
return "";
}
public String getLoginUserName() {
return loginUserName;
}
public void setLoginUserName(String loginUserName) {
this.loginUserName = loginUserName;
}
public String getLoginPassword() {
return loginPassword;
}
public void setLoginPassword(String loginPassword) {
this.loginPassword = loginPassword;
}
}
I want to be able to view the logged user from other areas in the application. I think I am injecting it incorrectly because loggedUser is always null when I am in a different bean for example something like..
#Stateless
#LocalBean
public class HistoryEJB {
#PersistenceContext
EntityManager em;
#ManagedProperty(value = "#{loggedUser}")
private LoggedUser loggedUser;
public LoggedUser getLoggedUser() {
return loggedUser;
}
public void setLoggedUser(LoggedUser loggedUser) {
this.loggedUser = loggedUser;
}
public void testLoggedUser() {
loggedUser.getLoggedUser();
// Just an example but would be null here - why?
}
}
How can I access this property from other areas in my application? Thanks for any help.
You can't use #ManagedProperty in an EJB and you shouldn't inject a view component into a business-tier component, period. #ManagedProperty is strictly web-tier stuff and is able to inject only and into web-tier, JSF components.
Your EJB ought to have a method that accepts a LoggedUser. This way, you can then pass your logged-in user to the EJB (which is the proper flow of data in a web application). What you have now is just turning best practice on its head.
So
Add a provideLoggedUser(LoggedUser loggedUser) method to your EJB
Call that method on your instance of UserEJB from within your managed bean
Rule of Thumb: Your EJB should not be aware of the web application
It seems you are missing the setter and getter for loggedUser. In principe it is there but it is convention to name it as follows
setProperty
and
setProperty
for a field named property. Note the capital first letter of the field name in the setter and getter!

CDI: Inject different bean in an EJB depending on the caller

I'm trying to inject a bean in a stateless EJB. But i would like that bean be different when EJB is called from a ManagedBean or from a EJB Timer.
Here is my EJB in which i inject a User bean:
MyEjb.java
#Stateless
class MyEjb{
#Inject
#CurrentContext
private User user;
public void foo(){
System.out.println(user);
}
}
Here is a EJB Timer that use the EJB:
TimerTest.java
#Singleton
#Startup
class TimerTest {
#EJB
private MyEjb myEjb;
#Timeout
public void doIt(Timer timer) {
myEjb.foo();
}
#Produces
#CurrentContext
public User produceCurrentUserInEjbTimer(){
return new User("system");
}
}
Finally, the ManagedBean using MyEjb :
MyManagedBean.java
#ManagedBean
#SessionScoped
class MyManagedBean {
#EJB
private MyEjb myEjb;
public void bar() {
myEjb.foo();
}
#Produces
#CurrentContext
#RequestScoped
public User produceCurrentUserInManagedBean(){
return new User(FacesContext.getCurrentInstance().getExternalContext().getRemoteUser());
}
}
When the timeout is reach, i would like that foo method of MyEbj use the system User created by the method produceCurrentUserInEjbTimer.
And when the bar method of the ManagedBean is invoked, i would like that foo method of MyEbj use the remote User of the FaceContext (created by the method produceCurrentUserInManagedBean).
I would rather have only one producer that checks if FacesContext.getCurrentInstance() != null then call the apropriate code:
public User produceCurrentUser(){
if(FacesContext.getCurrentInstance() != null){
return new User(FacesContext.getCurrentInstance().getExternalContext().getRemoteUser());
}
else{
return new User("system");
}
}
You can also inject you User directly on the timer or the ManagedBean and then use InjectionPoint object to know to which class your User is injected:
public User produceCurrentUser(InjectionPoint injectionPoint){
System.out.println(injectionPoint.getBean());
}
You should also use #Named and #javax.enterprise.context.SessionScoped as you have CDI on your application instead of #ManagedBean.
UPDATE
I'm not sure that there is a direct method to get the context of the injection, it wil be possible throw CDI extension but I've never try it.
What about obtaining a contextual instance by programmatic lookup:
#Stateless
class MyEjb{
#Inject #Any Instance<User> userSource;
public void foo(String context) // you should define contexts your self as jms, jsf ...
{
// Every expected context will have a qualifier
Annotation qualifier = context.equals("jsf") ?
new JSFQualifier() : new JMSQualifier();
User p = userSource.select(qualifier).get();
System.out.println(user);
}
}
This was you can inject your EJB and pass the context param to foo:
#Named
#SessionScoped
class MyManagedBean {
#EJB
private MyEjb myEjb;
public void bar() {
myEjb.foo("jsf");
}
}

How to call managed bean inside of stateless EJB bean?

I wanted to know, is there any option to call a managed bean inside of EJB bean. Imagine, we have the code:
#ManagedBean
#SessionScoped
public class MyManagedBean implements Serializable {
public String getUrl() {
return "http://www.google.com";
}
}
#Stateless
public class MyEJB {
#ManagedProperty(value = "#{myManagedBean}")
MyManagedBean myManagedBean;
public void setMyManagedBean(MyManagedBean myManagedBean) {
this.myManagedBean = myManagedBean;
}
public void call() {
// NullPointerException here
System.out.println(myManagedBean.getUrl());
}
}
I also tried this:
#Stateless
public class MyEJB {
#EJB
MyManagedBean myManagedBean;
...
}
... but it returns different MyManagedBean instance.
This is not right. With CDI managed beans instead of JSF managed beans it's possible, but it is just not right as in, bad design. The business service should not be aware about the front-end at all. It makes the business service unreusable on other front-ends than JSF.
You should do it the other way round. You should inject the EJB in the managed bean, not the other way round. The EJB should be kept entirely stateless. You should just directly pass the EJB the information it needs as method argument (and never assign it as instance variable of EJB afterwards).
E.g.
#ManagedBean
#SessionScoped // <-- Did you read https://stackoverflow.com/q/7031885?
public class MyManagedBean implements Serializable {
private String url = "http://www.google.com";
#EJB
private MyEJB myEJB;
public void submit() {
myEJB.call(url);
}
public String getUrl() {
return url;
}
}
and
#Stateless
public class MyEJB {
public void call(String url) {
// No NullPointerException here.
System.out.println(url);
}
}
See also:
JSF Service Layer

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