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 * Copyright (c) 2010, 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
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 */

package javax.net.ssl;

import java.util.List;

/**
 * Extends the <code>SSLSession</code> interface to support additional
 * session attributes.
 *
 * @since 1.7
 */
public abstract class ExtendedSSLSession implements SSLSession {
    /**
     * Obtains an array of supported signature algorithms that the local side
     * is willing to use.
     * <p>
     * Note: this method is used to indicate to the peer which signature
     * algorithms may be used for digital signatures in TLS 1.2. It is
     * not meaningful for TLS versions prior to 1.2.
     * <p>
     * The signature algorithm name must be a standard Java Security
     * name (such as "SHA1withRSA", "SHA256withECDSA", and so on).
     * See Appendix A in the <a href=
     * "https://docs.oracle.com/javase/8/docs/technotes/guides/security/crypto/CryptoSpec.html#AppA">
     * Java Cryptography Architecture API Specification &amp; Reference </a>
     * for information about standard algorithm names.
     * <p>
     * Note: the local supported signature algorithms should conform to
     * the algorithm constraints specified by
     * {@link SSLParameters#getAlgorithmConstraints getAlgorithmConstraints()}
     * method in <code>SSLParameters</code>.
     *
     * @return An array of supported signature algorithms, in descending
     *     order of preference.  The return value is an empty array if
     *     no signature algorithm is supported.
     *
     * @see SSLParameters#getAlgorithmConstraints
     */
    public abstract String[] getLocalSupportedSignatureAlgorithms();

    /**
     * Obtains an array of supported signature algorithms that the peer is
     * able to use.
     * <p>
     * Note: this method is used to indicate to the local side which signature
     * algorithms may be used for digital signatures in TLS 1.2. It is
     * not meaningful for TLS versions prior to 1.2.
     * <p>
     * The signature algorithm name must be a standard Java Security
     * name (such as "SHA1withRSA", "SHA256withECDSA", and so on).
     * See Appendix A in the <a href=
     * "https://docs.oracle.com/javase/8/docs/technotes/guides/security/crypto/CryptoSpec.html#AppA">
     * Java Cryptography Architecture API Specification &amp; Reference </a>
     * for information about standard algorithm names.
     *
     * @return An array of supported signature algorithms, in descending
     *     order of preference.  The return value is an empty array if
     *     the peer has not sent the supported signature algorithms.
     *
     * @see X509KeyManager
     * @see X509ExtendedKeyManager
     */
    public abstract String[] getPeerSupportedSignatureAlgorithms();

    /**
     * Obtains a {@link List} containing all {@link SNIServerName}s
     * of the requested Server Name Indication (SNI) extension.
     * <P>
     * In server mode, unless the return {@link List} is empty,
     * the server should use the requested server names to guide its
     * selection of an appropriate authentication certificate, and/or
     * other aspects of security policy.
     * <P>
     * In client mode, unless the return {@link List} is empty,
     * the client should use the requested server names to guide its
     * endpoint identification of the peer's identity, and/or
     * other aspects of security policy.
     *
     * @return a non-null immutable list of {@link SNIServerName}s of the
     *         requested server name indications. The returned list may be
     *         empty if no server name indications were requested.
     * @throws UnsupportedOperationException if the underlying provider
     *         does not implement the operation
     *
     * @see SNIServerName
     * @see X509ExtendedTrustManager
     * @see X509ExtendedKeyManager
     *
     * @since 1.8
     */
    public List<SNIServerName> getRequestedServerNames() {
        throw new UnsupportedOperationException();
    }
}
