001/* A logical NOT operator.
002
003 Copyright (c) 1997-2014 The Regents of the University of California.
004 All rights reserved.
005 Permission is hereby granted, without written agreement and without
006 license or royalty fees, to use, copy, modify, and distribute this
007 software and its documentation for any purpose, provided that the above
008 copyright notice and the following two paragraphs appear in all copies
009 of this software.
010
011 IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY
012 FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
013 ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
014 THE UNIVERSITY OF CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF
015 SUCH DAMAGE.
016
017 THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES,
018 INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
019 MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE
020 PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND THE UNIVERSITY OF
021 CALIFORNIA HAS NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES,
022 ENHANCEMENTS, OR MODIFICATIONS.
023
024 PT_COPYRIGHT_VERSION_2
025 COPYRIGHTENDKEY
026
027 */
028package ptolemy.actor.lib.logic;
029
030import ptolemy.actor.lib.Transformer;
031import ptolemy.data.BooleanToken;
032import ptolemy.data.type.BaseType;
033import ptolemy.kernel.CompositeEntity;
034import ptolemy.kernel.util.IllegalActionException;
035import ptolemy.kernel.util.NameDuplicationException;
036
037///////////////////////////////////////////////////////////////////
038//// LogicalNot
039
040/**
041 This actor implements a logical NOT operator.  It has one input and
042 one output port, neither of which is a multiport, and both of which have
043 type boolean.  A BooleanToken that arrives in the <i>input</i>
044 will be negated and sent on the <i>output</i>.
045 If no input token is available, then no output is produced.
046
047 @author John Li
048 @version $Id$
049 @since Ptolemy II 0.4
050 @Pt.ProposedRating Green (pwhitake)
051 @Pt.AcceptedRating Green (pwhitake)
052 */
053public class LogicalNot extends Transformer {
054    /** Construct an actor in the specified container with the specified
055     *  name.
056     *  @param container The container.
057     *  @param name The name of this actor within the container.
058     *  @exception IllegalActionException If the actor cannot be contained
059     *   by the proposed container.
060     *  @exception NameDuplicationException If the name coincides with
061     *   an actor already in the container.
062     */
063    public LogicalNot(CompositeEntity container, String name)
064            throws IllegalActionException, NameDuplicationException {
065        super(container, name);
066        input.setTypeEquals(BaseType.BOOLEAN);
067        output.setTypeEquals(BaseType.BOOLEAN);
068
069        _attachText("_iconDescription",
070                "<svg>\n" + "<rect x=\"-15\" y=\"-15\" "
071                        + "width=\"30\" height=\"30\" "
072                        + "style=\"fill:white\"/>\n" + "<text x=\"-4\" y=\"8\""
073                        + "style=\"font-size:24\">!</text>\n" + "</svg>\n");
074    }
075
076    ///////////////////////////////////////////////////////////////////
077    ////                         public methods                    ////
078
079    /** Consume exactly one token from the input, negate it, and send
080     *  it to the output.
081     *  @exception IllegalActionException If there is no director.
082     */
083    @Override
084    public void fire() throws IllegalActionException {
085        super.fire();
086        if (input.hasToken(0)) {
087            output.send(0, ((BooleanToken) input.get(0)).not());
088        }
089    }
090}