CorePlugin.java

/* ====================================================================
 *
 * The ObjectStyle Group Software License, Version 1.0
 *
 * Copyright (c) 2005 The ObjectStyle Group,
 * and individual authors of the software.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:
 *       "This product includes software developed by the
 *        ObjectStyle Group (http://objectstyle.org/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "ObjectStyle Group" and "Cayenne"
 *    must not be used to endorse or promote products derived
 *    from this software without prior written permission. For written
 *    permission, please contact andrus@objectstyle.org.
 *
 * 5. Products derived from this software may not be called "ObjectStyle"
 *    nor may "ObjectStyle" appear in their names without prior written
 *    permission of the ObjectStyle Group.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE OBJECTSTYLE GROUP OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the ObjectStyle Group.  For more
 * information on the ObjectStyle Group, please see
 * <http://objectstyle.org/>.
 *
 */
package org.objectstyle.wolips.core;

import java.util.ArrayList;
import java.util.List;

import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IConfigurationElement;
import org.eclipse.core.runtime.IExtension;
import org.eclipse.core.runtime.IExtensionPoint;
import org.eclipse.core.runtime.Platform;
import org.objectstyle.wolips.baseforuiplugins.AbstractBaseUIActivator;
import org.objectstyle.wolips.core.resources.builder.IBuilder;
import org.objectstyle.wolips.core.resources.internal.build.BuilderWrapper;
import org.osgi.framework.BundleContext;

/**
 * The main plugin class to be used in the desktop.
 */
public class CorePlugin extends AbstractBaseUIActivator {
	// The plug-in ID
	public static final String PLUGIN_ID = "org.objectstyle.wolips.core";

	// The shared instance.
	private static CorePlugin plugin;

	private BuilderWrapper[] builderWrapper;

	private static final String EXTENSION_POINT_ID = "org.objectstyle.wolips.builders";

	/**
	 * The constructor.
	 */
	public CorePlugin() {
		super();
		plugin = this;
	}

	/**
	 * This method is called when the plug-in is stopped
	 */
	public void stop(BundleContext context) throws Exception {
		super.stop(context);
		plugin = null;
		builderWrapper = null;
	}

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

	/**
	 * @return The builder defined in the builder extension point
	 * @throws CoreException
	 */
	private void loadBuilderExtensionPoint() {
		IExtensionPoint extensionPoint = Platform.getExtensionRegistry().getExtensionPoint(EXTENSION_POINT_ID);
		IExtension[] extensions = extensionPoint.getExtensions();
		List<BuilderWrapper> arrayList = new ArrayList<BuilderWrapper>();
		for (int i = 0; i < extensions.length; i++) {
			IConfigurationElement[] configurationElements = extensions[i].getConfigurationElements();
			for (int j = 0; j < configurationElements.length; j++) {
				IConfigurationElement configurationElement = configurationElements[j];
				IBuilder currentBuilder = null;
				try {
					currentBuilder = (IBuilder) configurationElement.createExecutableExtension("class");
					String name = configurationElement.getAttribute("name");
					String context = configurationElement.getAttribute("context");
					arrayList.add(new BuilderWrapper(currentBuilder, name, context));
				} catch (CoreException e) {
					this.log("Could not create executable from configuration element: " + configurationElement, e);
				}
			}
		}
		this.builderWrapper = arrayList.toArray(new BuilderWrapper[arrayList.size()]);
	}

	public BuilderWrapper[] getBuilderWrapper(String context) {
		if (this.builderWrapper == null) {
			loadBuilderExtensionPoint();
		}
		List<BuilderWrapper> builderWrapperList = new ArrayList<BuilderWrapper>();
		for (int i = 0; i < builderWrapper.length; i++) {
			BuilderWrapper currentBuilderWrapper = builderWrapper[i];
			if (currentBuilderWrapper.validInContext(context)) {
				builderWrapperList.add(currentBuilderWrapper);
			}
		}
		return builderWrapperList.toArray(new BuilderWrapper[builderWrapperList.size()]);
	}
}