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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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.EventObject;
import java.security.cert.Certificate;
import java.security.Principal;
import java.security.cert.X509Certificate;

/**
 * This event indicates that an SSL handshake completed on a given
 * SSL connection.  All of the core information about that handshake's
 * result is captured through an "SSLSession" object.  As a convenience,
 * this event class provides direct access to some important session
 * attributes.
 *
 * <P> The source of this event is the SSLSocket on which handshaking
 * just completed.
 *
 * @see SSLSocket
 * @see HandshakeCompletedListener
 * @see SSLSession
 *
 * @since 1.4
 * @author David Brownell
 */
public class HandshakeCompletedEvent extends EventObject
{
    private static final long serialVersionUID = 7914963744257769778L;

    private transient SSLSession session;

    /**
     * Constructs a new HandshakeCompletedEvent.
     *
     * @param sock the SSLSocket acting as the source of the event
     * @param s the SSLSession this event is associated with
     */
    public HandshakeCompletedEvent(SSLSocket sock, SSLSession s)
    {
        super(sock);
        session = s;
    }


    /**
     * Returns the session that triggered this event.
     *
     * @return the <code>SSLSession</code> for this handshake
     */
    public SSLSession getSession()
    {
        return session;
    }


    /**
     * Returns the cipher suite in use by the session which was produced
     * by the handshake.  (This is a convenience method for
     * getting the ciphersuite from the SSLsession.)
     *
     * @return the name of the cipher suite negotiated during this session.
     */
    public String getCipherSuite()
    {
        return session.getCipherSuite();
    }


    /**
     * Returns the certificate(s) that were sent to the peer during
     * handshaking.
     * Note: This method is useful only when using certificate-based
     * cipher suites.
     *
     * When multiple certificates are available for use in a
     * handshake, the implementation chooses what it considers the
     * "best" certificate chain available, and transmits that to
     * the other side.  This method allows the caller to know
     * which certificate chain was actually used.
     *
     * @return an ordered array of certificates, with the local
     *          certificate first followed by any
     *          certificate authorities.  If no certificates were sent,
     *          then null is returned.
     * @see #getLocalPrincipal()
     */
    public java.security.cert.Certificate [] getLocalCertificates()
    {
        return session.getLocalCertificates();
    }


    /**
     * Returns the identity of the peer which was established as part
     * of defining the session.
     * Note: This method can be used only when using certificate-based
     * cipher suites; using it with non-certificate-based cipher suites,
     * such as Kerberos, will throw an SSLPeerUnverifiedException.
     * <P>
     * Note: The returned value may not be a valid certificate chain
     * and should not be relied on for trust decisions.
     *
     * @return an ordered array of the peer certificates,
     *          with the peer's own certificate first followed by
     *          any certificate authorities.
     * @exception SSLPeerUnverifiedException if the peer is not verified.
     * @see #getPeerPrincipal()
     */
    public java.security.cert.Certificate [] getPeerCertificates()
            throws SSLPeerUnverifiedException
    {
        return session.getPeerCertificates();
    }


    /**
     * Returns the identity of the peer which was identified as part
     * of defining the session.
     * Note: This method can be used only when using certificate-based
     * cipher suites; using it with non-certificate-based cipher suites,
     * such as Kerberos, will throw an SSLPeerUnverifiedException.
     * <P>
     * Note: The returned value may not be a valid certificate chain
     * and should not be relied on for trust decisions.
     *
     * <p><em>Note: this method exists for compatibility with previous
     * releases. New applications should use
     * {@link #getPeerCertificates} instead.</em></p>
     *
     * @return an ordered array of peer X.509 certificates,
     *          with the peer's own certificate first followed by any
     *          certificate authorities.  (The certificates are in
     *          the original JSSE
     *          {@link javax.security.cert.X509Certificate} format).
     * @exception SSLPeerUnverifiedException if the peer is not verified.
     * @see #getPeerPrincipal()
     * @deprecated The {@link #getPeerCertificates()} method that returns an
     *               array of {@code java.security.cert.Certificate} should
     *               be used instead.
     */
    @Deprecated(since="9")
    public javax.security.cert.X509Certificate [] getPeerCertificateChain()
            throws SSLPeerUnverifiedException
    {
        return session.getPeerCertificateChain();
    }

    /**
     * Returns the identity of the peer which was established as part of
     * defining the session.
     *
     * @return the peer's principal. Returns an X500Principal of the
     * end-entity certiticate for X509-based cipher suites, and
     * KerberosPrincipal for Kerberos cipher suites.
     *
     * @throws SSLPeerUnverifiedException if the peer's identity has not
     *          been verified
     *
     * @see #getPeerCertificates()
     * @see #getLocalPrincipal()
     *
     * @since 1.5
     */
    public Principal getPeerPrincipal()
            throws SSLPeerUnverifiedException
    {
        Principal principal;
        try {
            principal = session.getPeerPrincipal();
        } catch (AbstractMethodError e) {
            // if the provider does not support it, fallback to peer certs.
            // return the X500Principal of the end-entity cert.
            Certificate[] certs = getPeerCertificates();
            principal = ((X509Certificate)certs[0]).getSubjectX500Principal();
        }
        return principal;
    }

    /**
     * Returns the principal that was sent to the peer during handshaking.
     *
     * @return the principal sent to the peer. Returns an X500Principal
     * of the end-entity certificate for X509-based cipher suites, and
     * KerberosPrincipal for Kerberos cipher suites. If no principal was
     * sent, then null is returned.
     *
     * @see #getLocalCertificates()
     * @see #getPeerPrincipal()
     *
     * @since 1.5
     */
    public Principal getLocalPrincipal()
    {
        Principal principal;
        try {
            principal = session.getLocalPrincipal();
        } catch (AbstractMethodError e) {
            principal = null;
            // if the provider does not support it, fallback to local certs.
            // return the X500Principal of the end-entity cert.
            Certificate[] certs = getLocalCertificates();
            if (certs != null) {
                principal =
                        ((X509Certificate)certs[0]).getSubjectX500Principal();
            }
        }
        return principal;
    }

    /**
     * Returns the socket which is the source of this event.
     * (This is a convenience function, to let applications
     * write code without type casts.)
     *
     * @return the socket on which the connection was made.
     */
    public SSLSocket getSocket()
    {
        return (SSLSocket) getSource();
    }
}
