/* Open a keystore from a FileParameter and output a SecretKey.

 @Copyright (c) 2003-2005 The Regents of the University of California.
 All rights reserved.

 Permission is hereby granted, without written agreement and without
 license or royalty fees, to use, copy, modify, and distribute this
 software and its documentation for any purpose, provided that the
 above copyright notice and the following two paragraphs appear in all
 copies of this software.

 IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY
 FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
 ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
 THE UNIVERSITY OF CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF
 SUCH DAMAGE.

 THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES,
 INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE
 PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND THE UNIVERSITY OF
 CALIFORNIA HAS NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES,
 ENHANCEMENTS, OR MODIFICATIONS.

 PT_COPYRIGHT_VERSION 2
 COPYRIGHTENDKEY
 */
package ptolemy.actor.lib.security;

import ptolemy.kernel.CompositeEntity;
import ptolemy.kernel.util.IllegalActionException;
import ptolemy.kernel.util.NameDuplicationException;
import ptolemy.kernel.util.Settable;

//////////////////////////////////////////////////////////////////////////
//// SecretKeyReader

/** Open a keystore from a FileParameter and output a SecretKey.

 <p>This class is a wrapper class for {@link KeyReader} that always
 returns a secret key.

 <p>The secret key is a symmetric key can be used by the {@link
 SymmetricEncryption} and {@link SymmetricDecryption} actors.
 See {@link ptolemy.actor.lib.security.SymmetricEncryption} for a
 description of symmetric vs. asymmetric algorithms.

 @see PrivateKeyReader
 @see PublicKeyReader
 @see SecretKey
 @see SignatureVerifier
 @author  Christopher Hylands Brooks
 @version $Id$
 @since Ptolemy II 4.0
 @Pt.ProposedRating Yellow (cxh)
 @Pt.AcceptedRating Red (cxh)
 */
public class SecretKeyReader extends PrivateKeyReader {
    /** Construct an actor with the given container and name.
     *  @param container The container.
     *  @param name The name of this actor.
     *  @exception IllegalActionException If the actor cannot be contained
     *   by the proposed container.
     *  @exception NameDuplicationException If the container already has an
     *   actor with this name.
     */
    public SecretKeyReader(CompositeEntity container, String name)
            throws IllegalActionException, NameDuplicationException {
        super(container, name);

        // SecretKeys do not have certificates.
        verifyCertificate.setExpression("false");

        // Hide the verifyCertificate Parameter.
        verifyCertificate.setVisibility(Settable.EXPERT);
    }
}