/*

 * Copyright (c) 2012, 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 java.security.cert;

/**

 * <p>Performs one or more checks on each {@code Certificate} of a

 * {@code CertPath}.

 *

 * <p>A {@code CertPathChecker} implementation is typically created to extend

 * a certification path validation algorithm. For example, an implementation

 * may check for and process a critical private extension of each certificate

 * in a certification path.

 *

 * @since 1.8

 */

public interface CertPathChecker {

    /**

     * Initializes the internal state of this {@code CertPathChecker}.

     *

     * <p>The {@code forward} flag specifies the order that certificates will

     * be passed to the {@link #check check} method (forward or reverse).

     *

     * @param forward the order that certificates are presented to the

     *        {@code check} method. If {@code true}, certificates are

     *        presented from target to trust anchor (forward); if

     *        {@code false}, from trust anchor to target (reverse).

     * @throws CertPathValidatorException if this {@code CertPathChecker} is

     *         unable to check certificates in the specified order

     */

    void init(boolean forward) throws CertPathValidatorException;

    /**

     * Indicates if forward checking is supported. Forward checking refers

     * to the ability of the {@code CertPathChecker} to perform its checks

     * when certificates are presented to the {@code check} method in the

     * forward direction (from target to trust anchor).

     *

     * @return {@code true} if forward checking is supported, {@code false}

     *         otherwise

     */

    boolean isForwardCheckingSupported();

    /**

     * Performs the check(s) on the specified certificate using its internal

     * state. The certificates are presented in the order specified by the

     * {@code init} method.

     *

     * @param cert the {@code Certificate} to be checked

     * @throws CertPathValidatorException if the specified certificate does

     *         not pass the check

     */

    void check(Certificate cert) throws CertPathValidatorException;

}