/*

 * Copyright (c) 2009, 2013, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package sun.net.www.protocol.http;

import java.io.IOException;

import java.lang.reflect.Constructor;

import sun.util.logging.PlatformLogger;

/**

 * This abstract class is a bridge to connect NegotiteAuthentication and

 * NegotiatorImpl, so that JAAS and JGSS calls can be made

 */

public abstract class Negotiator {

    static Negotiator getNegotiator(HttpCallerInfo hci) {

        // These lines are equivalent to

        // return new NegotiatorImpl(hci);

        // The current implementation will make sure NegotiatorImpl is not

        // directly referenced when compiling, thus smooth the way of building

        // the J2SE platform where HttpURLConnection is a bootstrap class.

        //

        // Makes NegotiatorImpl, and the security classes it references, a

        // runtime dependency rather than a static one.

        Class<?> clazz;

        Constructor<?> c;

        try {

            clazz = Class.forName("sun.net.www.protocol.http.spnego.NegotiatorImpl", true, null);

            c = clazz.getConstructor(HttpCallerInfo.class);

        } catch (ClassNotFoundException cnfe) {

            finest(cnfe);

            return null;

        } catch (ReflectiveOperationException roe) {

            // if the class is there then something seriously wrong if

            // the constructor is not.

            throw new AssertionError(roe);

        }

        try {

            return (Negotiator) (c.newInstance(hci));

        } catch (ReflectiveOperationException roe) {

            finest(roe);

            Throwable t = roe.getCause();

            if (t != null && t instanceof Exception)

                finest((Exception)t);

            return null;

        }

    }

    public abstract byte[] firstToken() throws IOException;

    public abstract byte[] nextToken(byte[] in) throws IOException;

    private static void finest(Exception e) {

        PlatformLogger logger = HttpURLConnection.getHttpLogger();

        if (logger.isLoggable(PlatformLogger.Level.FINEST)) {

            logger.finest("NegotiateAuthentication: " + e);

        }

    }

}