001/* Handle a model error.
002
003 Copyright (c) 2000-2013 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
030///////////////////////////////////////////////////////////////////
031//// ModelErrorHandler
032
033/**
034 Interface for model error handlers.  A model error is an exception that is
035 passed up the Ptolemy II hierarchy for handling until a container with
036 a registered error handler is found.  If there is no registered error
037 handler, then the error is ignored.  It is like throwing an exception, except
038 that instead of unraveling the calling stack, it travels up the Ptolemy II
039 hierarchy.
040 <p>
041 A typical use of this facility is where an actor does the following:
042 <pre>
043 handleModelError(this, new IllegalActionException(this, message));
044 </pre>
045 instead of this:
046 <pre>
047 throw new IllegalActionException(this, message);
048 </pre>
049 The former allows a container in the hierarchy to intercept the
050 exception, whereas the latter simply throws the exception.
051
052 @author Edward A. Lee
053 @version $Id$
054 @since Ptolemy II 2.1
055 @Pt.ProposedRating Green (eal)
056 @Pt.AcceptedRating Green (hyzheng)
057 */
058public interface ModelErrorHandler {
059    ///////////////////////////////////////////////////////////////////
060    ////                         public methods                    ////
061
062    /** Handle a model error.
063     *  @param context The object in which the error occurred.
064     *  @param exception An exception that represents the error.
065     *  @return True if the error has been handled, or false if the
066     *   error is not handled.
067     *  @exception IllegalActionException If the handler handles the
068     *   error by throwing an exception.
069     */
070    public boolean handleModelError(NamedObj context,
071            IllegalActionException exception) throws IllegalActionException;
072}