| Title: Collapsed EAR |
| <a name="CollapsedEAR-Onearchive"></a> |
| # One archive |
| |
| The basic idea of this approach is that your Servlets and EJBs are together |
| in your WAR file as one app. |
| |
| * No classloader boundries between Servlets and EJBs |
| * EJBs and Servlets can share all third-party libraries (like Spring\!) - no EAR required. |
| * Can put the web.xml and ejb-jar.xml in the same archive (the WAR file). |
| * EJBs can see Servlet classes and vice versa. |
| |
| <a name="CollapsedEAR-NotquiteJ2EE(itistrulyJava EE6)"></a> |
| # Not quite J2EE (it is truly Java EE6) |
| |
| This is very different than J2EE or Java EE 5 as there aren't several |
| levels of separation and classloader hierarchy. This is going to take some |
| getting used to and it should be understood that this style of packaging |
| isn't J2EE compliant. Who would care tough as it is a feature of Java EE 6 |
| we would've been waiting for so long. |
| |
| J2EE classloading rules: |
| |
| * You cannot ever have EJBs and servlets in the same classloader. |
| * Three classloader minimum; a classloader for the ear, one for each ejb-jar, and one for each WAR file. |
| * Servlets can see EJBs, but EJBs cannot see servlets. |
| |
| To pull that off, J2EE has to kill you on packaging: |
| * You cannot have EJB classes and Servlet classes in the same archive. |
| * You need at least three archives to combine servlets and ejbs; 1 EAR containing 1 EJB jar and 1 servlet WAR. |
| * Shared libraries must go in the EAR and be included in a specially formatted 'Class-Path' entry in the EAR's MANIFEST file. |
| |
| Critically speaking, forcing more than one classloader on an application |
| is where J2EE "jumps the shark" for a large majority of people's needs. |
| |
| <a name="CollapsedEAR-ExamplewithTomcat"></a> |
| # Example with Tomcat |
| |
| If you want to try to work with Servlets/JSP and OpenEJB using Tomcat, see |
| the [setup page](openejbx30:tomcat.html) |
| and the "/webapps/ejb-examples" section of the [openejb-examples.zip](downloads.html) |
| available on the [download page](http://tomee.apache.org/downloads.html). |
