ejb-3.1

问题 I'm new in here and also new to the CDI world, and the first task I got in my job was to find out a way to controlled CDI uploading. We are using both EJB 3.1 and CDI 1.0 , and because they are controlled by different containers, we can control when and in what order the EJB Managed Beans will be up by using @Startup and @Singleton annotations. But the @Inject CDI bean I have declared in my class is coming as null since the CDI Container hasn't started yet. I have been trying for several days

问题 I would like to develop an application with CDI (I use Spring usually) to discover this technology. I have read many articles about CDI to learn how it works. I have a simple question about transaction management (for persistence in database for example): Is it mandatory to use EJB 3.1 to have transaction management or is it possible to have it with CDI only ? Thanks. 回答1: No, you can do it with CDI. You simply need to create an interceptor that starts, commits or rollsback a transaction. It

问题 Given: simple JSF webapp (no Seam), having JSF beans calling few EJB's which in turn load and persist JPA entities. What I want to is to use @Singleton annotation for ejb's and inject EntityManager instead of EntityManagerFactory : @Singleton public class MyEJB { @PersistenceContext(unitName = PERSISTENCE_UNIT_NAME) protected EntityManager em; // not EntityManagerFactory } Spec says that @Singleton is thread-safe, supports concurrency and transaction attributes which (from my pov) makes it

问题 I'm confused between two attributes of @Resource annotation. Java Documentations says : mappedName : A product specific name that this resource should be mapped to. The name of this resource, as defined by the name element or defaulted, is a name that is local to the application component using the resource. (It's a name in the JNDI java:comp/env namespace.) Many application servers provide a way to map these local names to names of resources known to the application server. This mapped name

问题 How is the session defined in @SessionScoped CDI bean? Is this annotation valid only when called from Servlet container, where the session is well defined in form of HttpSession ? If not, than how an EJB with @Inject @SessionScoped MyBean myBean can know what the session really is ? I mean, methods of this EJB could have been invoked by a standalone client, RESTful WS or by some other view. What should happen in such case? Should the annotation have no meaning, should it inject fresh MyBean

问题 In the context of a Java EE 6 application run on WebSphere 8.0, I need to execute a number of startup tasks before any business method can be executed. Using a @Startup @Singleton bean for this purpose seems like a promising solution. However, it is not entirely clear to me how exactly the application lifecycle would look like. The EJB 3.1 spec states the following: By default, the container is responsible for deciding when to initialize a Singleton bean instance. However, the bean developer

问题 I am using weld ,a RI of CDI as dependency injection component in my JSF-EJB-JPA web app. I see in my project we have empty beans.xml in META-INF/beans.xml in ejb.jar and WEB-INF/beans.xml in my WAR. I don't get it why we need to keep empty beans.xml when there nothing defined in that file? 回答1: CDI needs to scan all the classes of a bean archive at start-up and fire a bunch of events because almost any class is automatically a managed bean (read more here), even if it doesn't have any

问题 What Maven repository can I use for EJB 3.1 API dependency? 回答1: This dependency from central worked. <dependency> <groupId>javax</groupId> <artifactId>javaee-api</artifactId> <version>6.0</version> <scope>provided</scope> </dependency> 来源： https://stackoverflow.com/questions/2429245/maven-repository-for-ejb-3-1-api

问题 I want to get bean from producer method in order to read its properties. In some scenarios the bean is a EJB Singleton bean. I've simplified my code to focus on the problem. My simple qualifier: @Qualifier @Retention(RUNTIME) @Target({TYPE, METHOD, FIELD, PARAMETER}) public @interface InjectMe {} Simple producer: @Dependent public class SimpleProducer { @Produces @InjectMe public String getInjectMe(InjectionPoint ip) { // ip.getBean() returns null for some reason return "ip=" + ip + ", bean="

问题 I want to get bean from producer method in order to read its properties. In some scenarios the bean is a EJB Singleton bean. I've simplified my code to focus on the problem. My simple qualifier: @Qualifier @Retention(RUNTIME) @Target({TYPE, METHOD, FIELD, PARAMETER}) public @interface InjectMe {} Simple producer: @Dependent public class SimpleProducer { @Produces @InjectMe public String getInjectMe(InjectionPoint ip) { // ip.getBean() returns null for some reason return "ip=" + ip + ", bean="