Inject an Ejb into Jax-Rs (Restful Service)

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;

/**
 * JAX-RS EJB Injection provider.
 */
@Provider
public class EJBProvider implements InjectableProvider<EJB, Type> {

    public ComponentScope getScope() {
        return ComponentScope.Singleton;
    }

    public Injectable getInjectable(ComponentContext cc, EJB ejb, Type t) {
        if (!(t instanceof Class)) return null;

        try {
            Class c = (Class)t;
            Context ic = new InitialContext();

            final Object o = ic.lookup(c.getName());

            return new Injectable<Object>() {
                public Object getValue() {
                    return o;
                }
            };
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }
}

Option 2: Make the BookResource an EJB

@Stateless
@Path("book")
public class BookResource {

    @EJB
    private BookEJB bookEJB;

    //...
}

See:

• How to Combine REST Services with EJB 3.1
• EJB 3.1 And REST - The Lightweight Hybrid

Option 3: Use CDI

@Path("book")
@RequestScoped
public class BookResource {

    @Inject
    private BookEJB bookEJB;

    //...
}

See:

• Injecting an EJB from a jar into a jax-rs class in a war

Interface EJB bean is not injected in JAX-RS Implementation class?

ImplementationRest EJB bean is instaniated using javax.ws.rs.core.Application instead EJB Container.

public class RestServiceInvoke1 extends Application {

@Override
public Set<Class<?>> getClasses() {
    Set<Class<?>> classes = new HashSet<Class<?>>();
    classes.add(ImplementationRest.class);
    return classes;
}}

This is the reason EJB Bean classes not injected in to anohter Bean that instantiated via javax.ws.rs.core.Application. Afterwards i achieved this implementation by Spring Framework like ejb-local-ref in web.xml , jee:jndi-lookup in bean.xml. Please go through with IBM Support URLs.

Go through below link for Summarizing this issue.

http://wedowebsphere.de/blogpost/accessing-jpa-jax-rs-service-directly

Cant inject Bean class into Restfull WebService (JAX-RS)

The @EJB annotation is not supposed to work for all objects.

For this to work you need to use CDI, so substitute the @EJB with @Inject and your bean will be correctly injected.

See also: Inject an EJB into JAX-RS (RESTful service)

EDIT:

Also be sure to add beans.xml to every jar/war archive containing classes you want to inject or be injected. It goes into META-INF for jars and WEB-INF for wars.

Your REST application class packaget.Rest should extend javax.ws.rs.core.Application as in:

@ApplicationPath("/root-path") 
public class Rest extends Application 
{ 
}

And according to the documentation here on JBoss 6.1 REST and CDI should work out of the box. If you specify the org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher and the org.jboss.resteasy.plugins.server.servlet.ResteasyBootstrap you are probably messing up the RestEasy/CDI classloading.

So your web.xml should look as:

<web-app version="3.0" xmlns="http://java.sun.com/xml/ns/javaee" 
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee java.sun.com/xml/ns/javaee/…"> 
</web-app> 

Anyway, I pushed a working example on github

JAVA-EE7/javax.ws.rs: Injection of EJB in REST-Resource

Try this:

@ApplicationPath("/rest")
public class RestConfiguration extends Application {

    private Set<Class<?>> resources = new HashSet<Class<?>>();

    public RestConfiguration () {
        resources.add(RegistrationRest.class);
    }

    @Override
    public Set<Class<?>> getClasses() {
        return resources;
    }

}

Make sure your web.xml has this:

<listener>
    <listener-class>org.jboss.resteasy.plugins.server.servlet.ResteasyBootstrap</listener-class>
</listener>

Finally, make sure you have beans.xml in your WEB-INF folder

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://java.sun.com/xml/ns/javaee"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="
      http://java.sun.com/xml/ns/javaee 
      http://java.sun.com/xml/ns/javaee/beans_1_0.xsd">
</beans>

EJB injection into Restful service (NullPointerException)

Declare the restful class with @Stateless, too. Here is an example: Inject an EJB into JAX-RS (RESTful service)

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