/*

 * Copyright (c) 2016, 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

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 * questions.

 */

package sun.net.www.protocol.http;

import java.net.Authenticator;

import java.util.concurrent.atomic.AtomicLong;

/**

 *  A class used to tie a key to an authenticator instance.

 */

public final class AuthenticatorKeys {

    private AuthenticatorKeys() {

        throw new InternalError("Trying to instantiate static class");

    }

    public static final String DEFAULT = "default";

    private static final AtomicLong IDS = new AtomicLong();

    public static String computeKey(Authenticator a) {

        return System.identityHashCode(a) + "-" + IDS.incrementAndGet()

               + "@" + a.getClass().getName();

    }

    /**

     * Returns a key for the given authenticator.

     *

     * @param authenticator The authenticator; {@code null} should be

     *        passed when the {@linkplain

     *        Authenticator#setDefault(java.net.Authenticator) default}

     *        authenticator is meant.

     * @return A key for the given authenticator, {@link #DEFAULT} for

     *         {@code null}.

     */

    public static String getKey(Authenticator authenticator) {

        if (authenticator == null) {

            return DEFAULT;

        }

        return authenticatorKeyAccess.getKey(authenticator);

    }

    @FunctionalInterface

    public interface AuthenticatorKeyAccess {

        public String getKey(Authenticator a);

    }

    private static AuthenticatorKeyAccess authenticatorKeyAccess;

    public static void setAuthenticatorKeyAccess(AuthenticatorKeyAccess access) {

        if (authenticatorKeyAccess == null && access != null) {

            authenticatorKeyAccess = access;

        }

    }

}