A Dysoweb application is at the same time an OSGi bundle and a mini "Web archive" (War) with some specificities (at least for the structure of the Web application)

OSGi Bundle

An OSGi bundle is usually a Jar file (altough at least Equinox and Felix support bundles as exploded directories) that contains some specific information in the manifest.

Therefore, a Dysoweb application will get the following from its bundle structure:

- META-INF/MANIFEST.MF
Contains the Bundle name, symbolic name, and version.

Activator : A java class that will be called when the application is started (see extensive OSGi litterature on the subject)
The activator must declare a "WebAppService" that will be used by the Dysoweb processor to register the application:

 /*

• (non-Javadoc)
• @see org.osgi.framework.BundleActivator#start(org.osgi.framework.BundleContext)
    */
   public void start(BundleContext context) throws Exception {
        fWebApp = context.registerService(WebAppService.class.getName(),
                  new WebAppService(context.getBundle()) { },
                  null);
   }

 /*

• (non-Javadoc)
• @see org.osgi.framework.BundleActivator#stop(org.osgi.framework.BundleContext)
    */
   public void stop(BundleContext context) throws Exception {
        unregister the web app service
        fWebApp.unregister();
        fWebApp = null;
   }

Creating an OSGi bundle

Class path

This is an important point, since WEB apps and OSGi bundles have a different way of specifiying which classes should be loaded.

In DysoWeb, the classes and librairies (jar) are loaded according to the OSGi spec, and are '''NOT loaded from WEB-INF/classes or WEB-INF/lib'''. They are loaded from the regular bundle class path (by default .), but it can be specified by the "Bundle-ClassPath" header in the manifest of the bundle.

Manifest Example

 Manifest-Version: 1.0
 Bundle-ManifestVersion: 2
 Bundle-Name: Test Plug-in
 Bundle-SymbolicName: com.requea.test
 Bundle-Version: 1.0.0
 Bundle-Activator: com.requea.test.Activator
 Import-Package: com.requea.dysoweb,
  org.osgi.framework;version="1.3.0"
 Bundle-ClassPath: bin/,
  .,
  lib/commons-lang-2.1.jar,
  lib/commons-resources.jar

Web App

The Web application content (static files, JSP, TLD, WEB-INF/web.xml) are put in the webapp directory in the bundle:

Therefore, the structure of a Dysoweb app looks like:

web.xml

The web.xml defined in webapp/WEB-INF/web.xml has a typical servlet application structure. You can define servlets, servlets mappings, filter and filter mappings.

 <?xml version="1.0" encoding="ISO-8859-1"?>
 <web-app>
     <display-name>Demo4 WebApp</display-name>
     <servlet>
         <servlet-name>voteServlet</servlet-name>
         <servlet-class>com.requea.dysoweb.demo4.VoteServlet</servlet-class>
         <load-on-startup>1</load-on-startup>
     </servlet>
     <servlet-mapping>
         <servlet-name>voteServlet</servlet-name>
         <url-pattern>/demo4/vote</url-pattern>
     </servlet-mapping>
 </web-app>