Copyright (c) 2003, 2012 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, 2012 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.storage.url.reference;

import java.io.IOException;
import java.net.*;

URLStreamHandler for reference protocol.  A reference URL is used to hold a 
reference to a local file URL.  A reference URL allows bundles to be installed
by reference.  This means the content of the bundle will not be copied.  Instead
the content of the bundle will be loaded from the reference location specified
by the reference URL.  The Framework only supports reference URLs that refer
to a local file URL.  For example: 

    reference:file:/eclipse/plugins/org.eclipse.myplugin_1.0.0/
    reference:file:/eclispe/plugins/org.eclipse.mybundle_1.0.0.jar

/**
 * URLStreamHandler for reference protocol.  A reference URL is used to hold a 
 * reference to a local file URL.  A reference URL allows bundles to be installed
 * by reference.  This means the content of the bundle will not be copied.  Instead
 * the content of the bundle will be loaded from the reference location specified
 * by the reference URL.  The Framework only supports reference URLs that refer
 * to a local file URL.  For example: <p>
 * <pre>
 *     reference:file:/eclipse/plugins/org.eclipse.myplugin_1.0.0/
 *     reference:file:/eclispe/plugins/org.eclipse.mybundle_1.0.0.jar
 * </pre>
 */
public class Handler extends URLStreamHandler {

	private final String installPath;

	public Handler(String installURL) {
		super();
		if (installURL != null && installURL.startsWith("file:")) { //$NON-NLS-1$
			// this is the safest way to create a File object off a file: URL
			this.installPath = installURL.substring(5);
		} else {
			this.installPath = null;
		}
	}

	
Throws:
IOException – /**
	 * @throws IOException  
	 */
	@Override
	protected URLConnection openConnection(URL url) throws IOException {
		return new ReferenceURLConnection(url, installPath);
	}

	@Override
	protected void parseURL(URL url, String str, int start, int end) {
		if (end < start) {
			return;
		}
		String reference = (start < end) ? str.substring(start, end) : url.getPath();

		setURL(url, url.getProtocol(), null, -1, null, null, reference, null, null);
	}

}