tests/org.eclipse.core.tests.runtime/src/org/eclipse/core/tests/runtime/TestAdapterFactoryLoader.java

/*******************************************************************************
 * Copyright (c) 2007, 2018 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM - Initial API and implementation
 *******************************************************************************/
package org.eclipse.core.tests.runtime;

import java.lang.reflect.InvocationTargetException;
import org.eclipse.core.runtime.*;
import org.junit.Assert;
import org.osgi.framework.Bundle;

/**
 * The adaptor factory to test scenario described in the bug 200068: adapting to
 * a class not reachable be the default class loader.
 *
 * This is a test code so almost all sanity checks are omitted (it is working on a known
 * hard-coded set of extensions and extension points). Also, for simplicity no trackers
 * or caching is done.
 */
public class TestAdapterFactoryLoader extends Assert implements IAdapterFactory {

	@Override
	public <T> T getAdapter(Object adaptableObject, Class<T> adapterType) {
		try {
			Class<?>[] targets = getAdapterList();
			return adapterType.cast(targets[0].getDeclaredConstructor().newInstance());
		} catch (InstantiationException | IllegalAccessException | IllegalArgumentException | InvocationTargetException
				| NoSuchMethodException | SecurityException e) {
			e.printStackTrace();
			fail("Unable to load target class");
			return null;
		}
	}

	@Override
	public Class<?>[] getAdapterList() {
		IExtensionRegistry registry = RegistryFactory.getRegistry();
		IExtensionPoint extPoint = registry.getExtensionPoint("org.eclipse.core.tests.runtime.factoryLoaderTest");
		IExtension[] extensions = extPoint.getExtensions();
		if (extensions.length == 0) {
			return new Class[0];
		}
		IExtension extension = extensions[0];
		IConfigurationElement[] confElements = extension.getConfigurationElements();
		String className = confElements[0].getAttribute("name");
		IContributor contributor = extension.getContributor();
		Bundle extensionBundle = ContributorFactoryOSGi.resolve(contributor);
		try {
			return new Class[] {extensionBundle.loadClass(className)};
		} catch (ClassNotFoundException e) {
			e.printStackTrace();
			fail("Unable to load class " + className);
			return null;
		}
	}
}