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Inject an EJB into JAX-RS (RESTful service)

I am not sure this is supposed to work. So either: Option 1: Use the injection provider SPI Implement a provider that will do the lookup and inject the EJB. See: @EJB injection. Example for com.sun.jersey:jersey-server:1.17 : import com.sun.jersey.core.spi.component.ComponentContext; import com.sun.jersey.core.spi.component.ComponentScope; import com.sun.jersey.spi.inject.Injectable; import com.sun.jersey.spi.inject.InjectableProvider; import javax.ejb.EJB; import javax.naming.Context; import javax.naming.InitialContext; import javax.ws.rs.ext.Provider; import java.lang.reflect.Type; … Read more

Why are data transfer objects (DTOs) an anti-pattern?

Some projects have all data twice. Once as domain objects, and once as data transfer objects. This duplication has a huge cost, so the architecture needs to get a huge benefit from this separation to be worth it.

How to deploy EJB based application on Tomcat

You can, but it’s not meant to happen that way. Tomcat is a servlet-container, and only application servers are required to support EJB. Tomcat with integrated EJB support is basically TomEE. Replace Tomcat by TomEE. You can keep using the Tomcat server plugin in IDE to manage TomEE.

How to inject @EJB, @PersistenceContext, @Inject, @Autowired, etc in @FacesConverter?

Can I use @EJB to inject my service into a @FacesConverter? No, not until JSF 2.3 is released. The JSF/CDI guys are working on that for JSF 2.3. See also JSF spec issue 1349 and this related “What’s new in JSF 2.3?” article of my fellow Arjan Tijms. Only then dependency injection like @EJB, @PersistenceContext, … Read more

Is it safe to manually start a new thread in Java EE?

Check out EJB 3.1 @Asynchronous methods. This is exactly what they are for. Small example that uses OpenEJB 4.0.0-SNAPSHOTs. Here we have a @Singleton bean with one method marked @Asynchronous. Every time that method is invoked by anyone, in this case your JSF managed bean, it will immediately return regardless of how long the method … Read more

When is it necessary or convenient to use Spring or EJB3 or all of them together?

First of all, Spring and EJB(+JTA) are competing technologies and usually not to be used together in the same application. Choose the one or the other. Spring or EJB(+JTA). I won’t tell you which to choose, I will only tell you a bit of history and the facts so that you can easier make the … Read more

What exactly is Java EE?

(Updated Feb 2022) First of all, “Java EE” has since Sep 2019 been renamed to “Jakarta EE“, starting with version 8. Historically, there was also the term “J2EE” which covered versions 1.2 until 1.4. The term “Java EE” covered versions 5 until 8. See also Jakarta EE, History on Wikipedia. Is Jakarta EE just a … Read more

JSF Controller, Service and DAO

Is this the correct way of doing things? Apart from performing business logic the inefficient way in a managed bean getter method, and using a too broad managed bean scope, it looks okay. If you move the service call from the getter method to a @PostConstruct method and use either @RequestScoped or @ViewScoped instead of … Read more