Moveable.java

/* Interface for objects that can can be moved in a list of objects.

 Copyright (c) 2004-2005 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.kernel.util;

//////////////////////////////////////////////////////////////////////////
//// Moveable

/**
 This is an interface for objects that can be moved in a list of
 objects in a container.

 @author Edward A. Lee
 @version $Id$
 @since Ptolemy II 4.1
 @Pt.ProposedRating Green (eal)
 @Pt.AcceptedRating Green (hyzheng)
 */
public interface Moveable {
    ///////////////////////////////////////////////////////////////////
    ////                         public methods                    ////

    /** Move this object down by one in the list of
     *  objects in its container. If the object is already last
     *  on the list, then it is not moved.
     *  @return The index of this object prior to moving it,
     *   or -1 if it is not moved.
     *  @exception IllegalActionException If this object has
     *   no container.
     */
    public int moveDown() throws IllegalActionException;

    /** Move this object to the first position in the list of
     *  objects in its container.  If the object is already
     *  first on the list, then it is not moved.
     *  @return The index of this object prior to moving it,
     *   or -1 if it is not moved.
     *  @exception IllegalActionException If this object has
     *   no container.
     */
    public int moveToFirst() throws IllegalActionException;

    /** Move this object to the specified position in the list of
     *  objects in its container, where 0 is the first position.
     *  If the object is already at the specified
     *  position, then it is not moved.
     *  @param index The position to which to move the object.
     *  @return The index of this object prior to moving it,
     *   or -1 if it is not moved.
     *  @exception IllegalActionException If this object has
     *   no container or if the index is out of range.
     */
    public int moveToIndex(int index) throws IllegalActionException;

    /** Move this object to the last position in the list of
     *  objects in its container.  If the object is already
     *  last on the list, then it is not moved.
     *  @return The index of this object prior to moving it,
     *   or -1 if it was not moved.
     *  @exception IllegalActionException If this object has
     *   no container.
     */
    public int moveToLast() throws IllegalActionException;

    /** Move this object up by one in the list of
     *  objects in its container.  If the object is already first
     *  on the list, then it is not moved.
     *  @return The index of this object prior to moving it,
     *   or -1 if it was not moved.
     *  @exception IllegalActionException If this object has
     *   no container.
     */
    public int moveUp() throws IllegalActionException;
}