Copyright (c) 2003, 2017 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 Corporation - initial API and implementation
/*******************************************************************************
 * Copyright (c) 2003, 2017 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 Corporation - initial API and implementation
 *******************************************************************************/

package org.eclipse.osgi.internal.loader;

import java.io.IOException;
import java.net.URL;
import java.util.Collection;
import java.util.Enumeration;
import org.eclipse.osgi.container.Module;
import org.eclipse.osgi.container.ModuleContainerAdaptor.ContainerEvent;
import org.eclipse.osgi.container.ModuleRevision;
import org.eclipse.osgi.container.ModuleWiring;
import org.eclipse.osgi.internal.framework.EquinoxConfiguration;
import org.eclipse.osgi.internal.framework.EquinoxContainer;
import org.eclipse.osgi.storage.BundleInfo.Generation;
import org.osgi.framework.BundleException;

The System Bundle's BundleLoader.  This BundleLoader is used by ImportClassLoaders
to load a resource that is exported by the System Bundle.
/**
 * The System Bundle's BundleLoader.  This BundleLoader is used by ImportClassLoaders
 * to load a resource that is exported by the System Bundle.
 */
public class SystemBundleLoader extends BundleLoader {
	public static final String EQUINOX_EE = "x-equinox-ee"; //$NON-NLS-1$
	final ClassLoader classLoader;
	final ModuleClassLoader moduleClassLoader;

	public SystemBundleLoader(ModuleWiring wiring, EquinoxContainer container, ClassLoader frameworkLoader) {
		super(wiring, container, frameworkLoader.getParent());
		this.classLoader = frameworkLoader;
		this.moduleClassLoader = new SystemModuleClassLoader(classLoader.getParent(), container.getConfiguration(), this, (Generation) wiring.getRevision().getRevisionInfo());
	}

	
The ClassLoader that loads OSGi framework classes is used to find the class.
This method never gets called because there is no BundleClassLoader for the framework.
/**
	 * The ClassLoader that loads OSGi framework classes is used to find the class.
	 * This method never gets called because there is no BundleClassLoader for the framework.
	 */
	@Override
	public Class<?> findClass(String name) throws ClassNotFoundException {
		Class<?> result = findLocalClass(name);
		if (result == null)
			throw new ClassNotFoundException(name);
		return result;
	}

	
The ClassLoader that loads OSGi framework classes is used to find the class. 
/**
	 * The ClassLoader that loads OSGi framework classes is used to find the class. 
	 */
	@Override
	public Class<?> findLocalClass(String name) {
		try {
			return classLoader.loadClass(name);
		} catch (ClassNotFoundException e) {
			// do nothing
			return null;
		}
	}

	
The ClassLoader that loads OSGi framework classes is used to find the resource.
/**
	 * The ClassLoader that loads OSGi framework classes is used to find the resource.
	 */
	@Override
	public URL findLocalResource(String name) {
		return classLoader.getResource(name);
	}

	
The ClassLoader that loads OSGi framework classes is used to find the resource.
/**
	 * The ClassLoader that loads OSGi framework classes is used to find the resource.
	 */
	@Override
	public Enumeration<URL> findLocalResources(String name) {
		try {
			return classLoader.getResources(name);
		} catch (IOException e) {
			// do nothing
			return null;
		}
	}

	
The ClassLoader that loads OSGi framework classes is used to find the resource.
This method never gets called because there is no ModuleClassLoader for the framework.
/**
	 * The ClassLoader that loads OSGi framework classes is used to find the resource.
	 * This method never gets called because there is no ModuleClassLoader for the framework.
	 */
	@Override
	public URL findResource(String name) {
		return findLocalResource(name);
	}

	
The ClassLoader that loads OSGi framework classes is used to find the resource.
This method never gets called because there is no ModuleClassLoader for the framework.
Throws:
IOException – /**
	 * The ClassLoader that loads OSGi framework classes is used to find the resource.
	 * This method never gets called because there is no ModuleClassLoader for the framework.
	 * @throws IOException 
	 */
	@Override
	public Enumeration<URL> findResources(String name) throws IOException {
		return findLocalResources(name);
	}

	@Override
	public ClassLoader getClassLoader() {
		return classLoader;
	}

	@Override
	public ModuleClassLoader getModuleClassLoader() {
		return moduleClassLoader;
	}

	@Override
	void loadClassLoaderFragments(Collection<ModuleRevision> fragments) {
		moduleClassLoader.loadFragments(fragments);
	}

	class SystemModuleClassLoader extends EquinoxClassLoader {

		public SystemModuleClassLoader(ClassLoader parent, EquinoxConfiguration configuration, BundleLoader delegate, Generation generation) {
			super(parent, configuration, delegate, generation);
		}

		@Override
		protected Class<?> loadClass(String name, boolean resolve) throws ClassNotFoundException {
			return SystemBundleLoader.this.findClass(name);
		}

		@Override
		public void loadFragments(Collection<ModuleRevision> fragments) {
			Module systemModule = getWiring().getRevision().getRevisions().getModule();
			try {
				this.getGeneration().getBundleInfo().getStorage().getExtensionInstaller().addExtensionContent(fragments, systemModule);
			} catch (BundleException e) {
				systemModule.getContainer().getAdaptor().publishContainerEvent(ContainerEvent.ERROR, systemModule, e);
			}
			getClasspathManager().loadFragments(fragments);
		}
	}
}