2 Replies Latest reply on Sep 8, 2012 3:00 AM by jaikiran

    Re: Remote EJB connections from one server to several servers

    fmessiaen
    fmessiaen Jun 1, 2012 9:49 AM

      Thank you very much for your help, Jaikiran PAI.

       

      I have a better understanding of the usage of the distinct name for the EJB invokation.

       

      I put a jboss-app.xml file in the META-INF directory of the EAR. I dynamicaly put the server name in the distinct-name tag :

       

       <?xml version="1.0" encoding="UTF-8"?>
<!--
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  ~ Copyright 2012, Red Hat, Inc., and individual contributors
  ~ as indicated by the @author tags. See the copyright.txt file in the
  ~ distribution for a full listing of individual contributors.
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  ~ published by the Free Software Foundation; either version 2.1 of
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  ~
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  ~ but WITHOUT ANY WARRANTY; without even the implied warranty of
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  ~ Lesser General Public License for more details.
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  ~ 02110-1301 USA, or see the FSF site: http://www.fsf.org.
  -->
<jboss-app xmlns="http://www.jboss.com/xml/ns/javaee"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
           xsi:schemaLocation="http://www.jboss.com/xml/ns/javaee http://www.jboss.org/noschema/jboss-app_5_0.xsd"
           version="5.0"
           id="jboss-app-id">
    <distinct-name>${jboss.server.name}</distinct-name>
</jboss-app>

       

      This way (without replacing the jboss.server.name property in that file), the content of the EAR file remains the same and the client only has to set in the distinct name the name of the server it wants to connect to.

       

      I tested it with the following code in the doGet method of my servlet:

      Greeter greeter_pcfme =  (Greeter) context.lookup("ejb:myapp/myejb/pc-fme/GreeterBean!" + org.myapp.ejb.Greeter.class.getName());
final String greeting_pcfme = greeter_pcfme.greet("fme");
Greeter greeter_pcfme2 =  (Greeter) context.lookup("ejb:myapp/myejb/pc-fme2/GreeterBean!" + org.myapp.ejb.Greeter.class.getName());
final String greeting_pcfme2 = greeter_pcfme2.greet("fme");
response.getWriter().append("<html><body>");
response.getWriter().append("Received greeting: " + greeting_pcfme);
response.getWriter().append("<br/>");
response.getWriter().append("Received greeting: " + greeting_pcfme2);
response.getWriter().append("</body></html>");

       

      And I got the following result each time I call the servlet :

       

      Received greeting: Hello fme, have a pleasant day! from pc-fme
Received greeting: Hello fme, have a pleasant day! from pc-fme2

       

      It is exactly the result we expect.

       

      I have one more related question : can we declared the list of ejb receivers whitout the jboss-ejb-client.xml file in the EAR file ? Is it possible to declared a default list of ejb receivers in a standalone.xml/domain.xml file ?

      This is to avoid a "branch" JBoss server to connect uselessly to others "branch" JBoss servers, as no data has to be directly exchanged between "branch" JBoss servers.

       

      Best regards,

       

      François