IncQueryRuntimePlugin.java

/*******************************************************************************
 * Copyright (c) 2004-2010 Gabor Bergmann and Daniel Varro
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *    Gabor Bergmann - initial API and implementation
 *******************************************************************************/
package org.eclipse.incquery.runtime;

import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IConfigurationElement;
import org.eclipse.core.runtime.Platform;
import org.eclipse.core.runtime.Plugin;
import org.eclipse.incquery.patternlanguage.emf.EMFPatternLanguageStandaloneSetup;
import org.eclipse.incquery.runtime.extensibility.IInjectorProvider;
import org.eclipse.incquery.runtime.internal.XtextInjectorProvider;
import org.osgi.framework.BundleContext;

import com.google.inject.Injector;

/**
 * The activator class controls the plug-in life cycle
 */
public class IncQueryRuntimePlugin extends Plugin {

    // The shared instance
    private static IncQueryRuntimePlugin plugin;

    public static final String PLUGIN_ID = "org.eclipse.incquery.runtime";

    /*
     * (non-Javadoc)
     * 
     * @see org.eclipse.core.runtime.Plugins#start(org.osgi.framework.BundleContext)
     */
    @Override
    public void start(BundleContext context) throws Exception {
        super.start(context);
        plugin = this;
        // TODO Builder registry may be used later
        // BuilderRegistry.initRegistry();
        XtextInjectorProvider.INSTANCE.setInjector(createInjector());
        // MatcherFactoryRegistry.initRegistry();
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.eclipse.core.runtime.Plugin#stop(org.osgi.framework.BundleContext)
     */
    @Override
    public void stop(BundleContext context) throws Exception {
        plugin = null;
        XtextInjectorProvider.INSTANCE.setInjector(null);
        super.stop(context);
    }

    /**
     * Returns the shared instance
     * 
     * @return the shared instance
     */
    public static IncQueryRuntimePlugin getDefault() {
        return plugin;
    }

    private Injector createInjector() throws CoreException {
        IConfigurationElement[] providers = Platform.getExtensionRegistry().getConfigurationElementsFor(
                IExtensions.INJECTOREXTENSIONID);
        if (providers.length > 0) {
            IConfigurationElement provider = providers[0]; // XXX multiple providers not supported
            IInjectorProvider injectorProvider = (IInjectorProvider) provider.createExecutableExtension("injector");
            return injectorProvider.getInjector();
        } else {
            return new EMFPatternLanguageStandaloneSetup().createInjector();
        }
    }

}