Red Hat Summit Red Hat SummitSuporteConsoleDesenvolvedoresComeçar um testeContato

Este conteúdo não está disponível no idioma selecionado.

Chapter 25. EJB

EJB Component
Copiar o link

Available as of Apache Camel 2.4
The ejb: component binds EJBs to message exchanges.

URI format
Copiar o link

ejb:ejbName[?options]
Copy to Clipboard Toggle word wrap
Where ejbName can be any string which is used to look up the EJB in the Application Server JNDI Registry

Options
Copiar o link

Expand
Name Type Default Description
method String null The method name that bean will be invoked. If not provided, Apache Camel will try to pick the method itself. In case of ambiguity an exception is thrown. See Bean Binding for more details.
multiParameterArray boolean false How to treat the parameters which are passed from the message body; if it is true, the In message body should be an array of parameters.
You can append query options to the URI in the following format, ?option=value&option=value&...
The EJB component extends the Bean component in which most of the details from the Bean component applies to this component as well.

Bean Binding
Copiar o link

How bean methods to be invoked are chosen (if they are not specified explicitly through the method parameter) and how parameter values are constructed from the MessageMessage are all defined by the Bean Binding mechanism which is used throughout all of the various Bean Integration mechanisms in Apache Camel.

Examples
Copiar o link

In the following examples we use the Greater EJB which is defined as follows: 
public interface GreaterLocal {

    String hello(String name);

    String bye(String name);

}
Copy to Clipboard Toggle word wrap
And the implementation 
@Stateless
public class GreaterImpl implements GreaterLocal {

    public String hello(String name) {
        return "Hello " + name;
    }

    public String bye(String name) {
        return "Bye " + name;
    }

}
Copy to Clipboard Toggle word wrap

Using Java DSL
Copiar o link

In this example we want to invoke the hello method on the EJB. Since this example is based on an unit test using Apache OpenEJB we have to set a JndiContext on the EJB component with the OpenEJB settings. 
@Override
protected CamelContext createCamelContext() throws Exception {
    CamelContext answer = new DefaultCamelContext();

    // enlist EJB component using the JndiContext
    EjbComponent ejb = answer.getComponent("ejb", EjbComponent.class);
    ejb.setContext(createEjbContext());

    return answer;
}

private static Context createEjbContext() throws NamingException {
    // here we need to define our context factory to use OpenEJB for our testing
    Properties properties = new Properties();
    properties.setProperty(Context.INITIAL_CONTEXT_FACTORY, "org.apache.openejb.client.LocalInitialContextFactory");

    return new InitialContext(properties);
}
Copy to Clipboard Toggle word wrap
Then we are ready to use the EJB in the Apache Camel route: 
from("direct:start")
    // invoke the greeter EJB using the local interface and invoke the hello method
    .to("ejb:GreaterImplLocal?method=hello")
    .to("mock:result");
Copy to Clipboard Toggle word wrap
Note
In a real application server you most likely do not have to setup a JndiContext on the EJB component as it will create a default JndiContext on the same JVM as the application server, which usually allows it to access the JNDI registry and lookup the EJBs. However if you need to access a application server on a remote JVM or the likes, you have to prepare the properties beforehand.

Using Spring XML
Copiar o link

And this is the same example using Spring XML instead:
Again since this is based on an unit test we need to setup the EJB component: 
<!-- setup Camel EJB component -->
<bean id="ejb" class="org.apache.camel.component.ejb.EjbComponent">
    <property name="properties" ref="jndiProperties"/>
</bean>

<!-- use OpenEJB context factory -->
<p:properties id="jndiProperties">
    <prop key="java.naming.factory.initial">org.apache.openejb.client.LocalInitialContextFactory</prop>
</p:properties>
Copy to Clipboard Toggle word wrap
Before we are ready to use EJB in the Apache Camel routes: 
<camelContext xmlns="http://camel.apache.org/schema/spring">
    <route>
        <from uri="direct:start"/>
        <to uri="ejb:GreaterImplLocal?method=hello"/>
        <to uri="mock:result"/>
    </route>
</camelContext>
Copy to Clipboard Toggle word wrap
Voltar ao topo
Red Hat logoGithubredditYoutubeTwitter

Aprender

Experimente, compre e venda

Comunidades

Sobre a documentação da Red Hat

Ajudamos os usuários da Red Hat a inovar e atingir seus objetivos com nossos produtos e serviços com conteúdo em que podem confiar. Explore nossas atualizações recentes.

Tornando o open source mais inclusivo

A Red Hat está comprometida em substituir a linguagem problemática em nosso código, documentação e propriedades da web. Para mais detalhes veja o Blog da Red Hat.

Sobre a Red Hat

Fornecemos soluções robustas que facilitam o trabalho das empresas em plataformas e ambientes, desde o data center principal até a borda da rede.

Theme

© 2025 Red Hat