Activator.java

package gr.upatras.ece.nam.fstoolkit.localprovisioningengine;

import org.osgi.framework.BundleActivator;
import org.osgi.framework.BundleContext;
import java.util.ArrayList;

import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IConfigurationElement;
import org.eclipse.core.runtime.ISafeRunnable;
import org.eclipse.core.runtime.Platform;
import org.eclipse.core.runtime.SafeRunner;
import org.eclipse.ui.plugin.AbstractUIPlugin;

import brokermodel.extensionInterfaces.IProvisionResource;


public class Activator extends AbstractUIPlugin {

	// The plug-in ID
		public static final String PLUGIN_ID = "gr.upatras.ece.nam.fstoolkit.localprovisioningengine"; //$NON-NLS-1$

		// The shared instance
		private static Activator plugin;
		
		//available provisioning plugins
		private ArrayList<IProvisionResource> provisionPlugins;
		
		/**
		 * @return the provisionPlugins
		 */
		public ArrayList<IProvisionResource> getProvisionPlugins() {
			return provisionPlugins;
		}

		/**
		 * The constructor
		 */
		public Activator() {
		}

		/*
		 * (non-Javadoc)
		 * @see org.eclipse.ui.plugin.AbstractUIPlugin#start(org.osgi.framework.BundleContext)
		 */
		public void start(BundleContext context) throws Exception {
			super.start(context);
			plugin = this;
			this.provisionPlugins = new ArrayList<IProvisionResource>();
			runProvisionResourceExtension(this.provisionPlugins);
		}

		/*
		 * (non-Javadoc)
		 * @see org.eclipse.ui.plugin.AbstractUIPlugin#stop(org.osgi.framework.BundleContext)
		 */
		public void stop(BundleContext context) throws Exception {
			plugin = null;
			super.stop(context);
		}

		/**
		 * Returns the shared instance
		 *
		 * @return the shared instance
		 */
		public static Activator getDefault() {
			return plugin;
		}
		
		
		// This is the ID from your extension point
		private static final String IPROVISIONRESOURCE_ID = "gr.upatras.ece.nam.fstoolkit.provisionresource";

		
		private void runProvisionResourceExtension(final ArrayList<IProvisionResource> provisionPlugins) {
			IConfigurationElement[] config = Platform.getExtensionRegistry().getConfigurationElementsFor(IPROVISIONRESOURCE_ID);
			
			try {
				for (IConfigurationElement e : config) {
					System.out.println("Evaluating extension "+IPROVISIONRESOURCE_ID);
					final Object o = e.createExecutableExtension("class");
					if (o instanceof IProvisionResource) {
						ISafeRunnable runnable = new ISafeRunnable() {
							@Override
							public void handleException(Throwable exception) {
								System.out.println("Exception in client");
							}

							@Override
							public void run() throws Exception {
								provisionPlugins.add( (IProvisionResource) o );
							}
						};
						SafeRunner.run(runnable);
					}
				}
			} catch (CoreException ex) {
				System.out.println(ex.getMessage());
			}
		}

	}