001/* A change listener that describes changes on the standard output.
002
003 Copyright (c) 1998-2014 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.kernel.util;
029
030import java.io.OutputStream;
031import java.io.PrintStream;
032
033///////////////////////////////////////////////////////////////////
034//// StreamChangeListener
035
036/**
037 A change listener that describes the changes on the standard output.
038 It simply prints the description of the change once it executes (or
039 throws an exception).
040
041 @author Edward A. Lee
042 @version $Id$
043 @since Ptolemy II 1.0
044 @Pt.ProposedRating Green (eal)
045 @Pt.AcceptedRating Green (neuendor)
046 */
047public class StreamChangeListener implements ChangeListener {
048    /** Create a change listener that sends messages to the standard output.
049     */
050    public StreamChangeListener() {
051        _output = System.out;
052    }
053
054    /** Create a change listener that sends messages to the specified stream.
055     *  @param out The stream to send messages to.
056     */
057    public StreamChangeListener(OutputStream out) {
058        _output = new PrintStream(out);
059    }
060
061    ///////////////////////////////////////////////////////////////////
062    ////                         public methods                    ////
063
064    /** Print the description of the change to the stream output.
065     *  @param change The change that has been executed.
066     */
067    @Override
068    public void changeExecuted(ChangeRequest change) {
069        String description = "";
070
071        if (change != null) {
072            description = change.getDescription();
073        }
074
075        _output.println("StreamChangeRequest.changeExecuted(): " + description
076                + " succeeded");
077    }
078
079    /** Print the description of the failure to the stream output.
080     *  @param change The change that has been executed.
081     *  @param exception The exception that occurred.
082     */
083    @Override
084    public void changeFailed(ChangeRequest change, Exception exception) {
085        String description = "";
086
087        if (change != null) {
088            description = change.getDescription();
089        }
090
091        _output.println("StreamChangeRequest.changeFailed(): " + description
092                + " failed: " + exception.toString());
093    }
094
095    ///////////////////////////////////////////////////////////////////
096    ////                         protected variables               ////
097
098    /** The PrintStream that we direct the output to. */
099    protected PrintStream _output;
100}