001/* SpinnerModel.java --
002   Copyright (C) 2003, 2004  Free Software Foundation, Inc.
003
004This file is part of GNU Classpath.
005
006GNU Classpath is free software; you can redistribute it and/or modify
007it under the terms of the GNU General Public License as published by
008the Free Software Foundation; either version 2, or (at your option)
009any later version.
010
011GNU Classpath is distributed in the hope that it will be useful, but
012WITHOUT ANY WARRANTY; without even the implied warranty of
013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014General Public License for more details.
015
016You should have received a copy of the GNU General Public License
017along with GNU Classpath; see the file COPYING.  If not, write to the
018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
01902110-1301 USA.
020
021Linking this library statically or dynamically with other modules is
022making a combined work based on this library.  Thus, the terms and
023conditions of the GNU General Public License cover the whole
024combination.
025
026As a special exception, the copyright holders of this library give you
027permission to link this library with independent modules to produce an
028executable, regardless of the license terms of these independent
029modules, and to copy and distribute the resulting executable under
030terms of your choice, provided that you also meet, for each linked
031independent module, the terms and conditions of the license of that
032module.  An independent module is a module which is not derived from
033or based on this library.  If you modify this library, you may extend
034this exception to your version of the library, but you are not
035obligated to do so.  If you do not wish to do so, delete this
036exception statement from your version. */
037
038
039package javax.swing;
040
041import javax.swing.event.ChangeListener;
042
043/**
044 * The data model that is used in {@link JSpinner}s.
045 *
046 * @since 1.4
047 */
048public interface SpinnerModel
049{
050  /**
051   * Sets the current value of the model to that specified.
052   * Implementations can choose to refuse to accept the value
053   * and throw an exception instead.  For example, a date model
054   * may throw invalid dates, or a list model may throw out
055   * values which don't exist in the underlying list.  Models
056   * may also throw out unusual values, such as null.  The decision
057   * is left to the discretion of the implementator.  If the
058   * operation succeeds, the implementation should also notify
059   * any registered <code>ChangeListener</code>s.
060   *
061   * @param value The new value of the model.
062   * @throws IllegalArgumentException if the model does not accept
063   *         the given value.
064   */
065  void setValue(Object value);
066
067  /**
068   * Returns the current value of the model.
069   *
070   * @return The current value.
071   */
072  Object getValue();
073
074  /**
075   * Returns the next value from the model.  If the model is bounded,
076   * this method may return null when the upper bound is met.
077   * The current value is not changed.
078   *
079   * @return The next value, or null if there are no more values
080   *         to retrieve.
081   */
082  Object getNextValue();
083
084  /**
085   * Returns the previous value from the model.  If the model is
086   * bounded, this method may return null when the lower bound is
087   * met.  The current value is not changed.
088   *
089   * @return The previous value, or null if there are no more
090   *         values to retrieve.
091   */
092  Object getPreviousValue();
093
094  /**
095   * Adds a <code>ChangeListener</code> to the list of registered
096   * listeners.  Each listener is notified when the current value
097   * is changed.
098   *
099   * @param listener The new listener to register.
100   */
101  void addChangeListener(ChangeListener listener);
102
103  /**
104   * Removes a given <code>ChangeListener</code> from the list
105   * of registered listeners.
106   *
107   * @param listener The listener to remove.
108   */
109  void removeChangeListener(ChangeListener listener);
110
111}