Copyright (c) 2000, 2015 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
    Sergey Prigogin (Google) - use parameterized types (bug 442021)
/*******************************************************************************
 * Copyright (c) 2000, 2015 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
 *     Sergey Prigogin (Google) - use parameterized types (bug 442021)
 *******************************************************************************/
package org.eclipse.core.internal.boot;

import java.io.IOException;
import java.lang.reflect.Constructor;
import java.net.*;
import java.util.Hashtable;
import org.eclipse.core.internal.runtime.CommonMessages;
import org.eclipse.osgi.util.NLS;
import org.osgi.service.url.AbstractURLStreamHandlerService;

URL handler for the "platform" protocol
/**
 * URL handler for the "platform" protocol
 */
public class PlatformURLHandler extends AbstractURLStreamHandlerService {

	private static Hashtable<String, Constructor<?>> connectionType = new Hashtable<>();

	// URL protocol designations
	public static final String PROTOCOL = "platform"; //$NON-NLS-1$
	public static final String FILE = "file"; //$NON-NLS-1$
	public static final String JAR = "jar"; //$NON-NLS-1$
	public static final String BUNDLE = "bundle"; //$NON-NLS-1$
	public static final String JAR_SEPARATOR = "!/"; //$NON-NLS-1$
	public static final String PROTOCOL_SEPARATOR = ":"; //$NON-NLS-1$

	/*
	 * Constructor for the class.
	 */
	public PlatformURLHandler() {
		super();
	}

	@Override
	public URLConnection openConnection(URL url) throws IOException {
		// Note: openConnection() method is made public (rather than protected)
		//       to enable request delegation from proxy handlers
		String spec = url.getFile().trim();
		if (spec.startsWith("/")) //$NON-NLS-1$
			spec = spec.substring(1);
		int ix = spec.indexOf('/'); //$NON-NLS-1$
		if (ix == -1)
			throw new MalformedURLException(NLS.bind(CommonMessages.url_invalidURL, url.toExternalForm()));

		String type = spec.substring(0, ix);
		Constructor<?> construct = connectionType.get(type);
		if (construct == null)
			throw new MalformedURLException(NLS.bind(CommonMessages.url_badVariant, type));

		PlatformURLConnection connection = null;
		try {
			connection = (PlatformURLConnection) construct.newInstance(new Object[] {url});
		} catch (Exception e) {
			throw new IOException(NLS.bind(CommonMessages.url_createConnection, e.getMessage()));
		}
		connection.setResolvedURL(connection.resolve());
		return connection;
	}

	public static void register(String type, Class<?> connectionClass) {
		try {
			Constructor<?> c = connectionClass.getConstructor(new Class[] {URL.class});
			connectionType.put(type, c);
		} catch (NoSuchMethodException e) {
			//don't register connection classes that don't conform to the spec
		}
	}

	public static void unregister(String type) {
		connectionType.remove(type);
	}
}