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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
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* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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package javax.swing;
import java.awt.event.*;
import javax.swing.event.*;
/**
* A model for a potentially unbounded sequence of object values. This model
* is similar to <code>ListModel</code> however there are some important differences:
* <ul>
* <li> The number of sequence elements isn't neccessarily bounded.
* <li> The model doesn't support indexed random access to sequence elements.
* Only three sequence values are accessible at a time: current, next and
* previous.
* <li> The current sequence element, can be set.
* </ul>
* <p>
* A <code>SpinnerModel</code> has three properties, only the first is read/write.
* <dl>
* <dt><code>value</code>
* <dd>The current element of the sequence.
*
* <dt><code>nextValue</code>
* <dd>The following element or null if <code>value</code> is the
* last element of the sequence.
*
* <dt><code>previousValue</code>
* <dd>The preceeding element or null if <code>value</code> is the
* first element of the sequence.
* </dl>
* When the the <code>value</code> property changes,
* <code>ChangeListeners</code> are notified. <code>SpinnerModel</code> may
* choose to notify the <code>ChangeListeners</code> under other circumstances.
*
* @see JSpinner
* @see AbstractSpinnerModel
* @see SpinnerListModel
* @see SpinnerNumberModel
* @see SpinnerDateModel
*
* @author Hans Muller
* @since 1.4
*/
public interface SpinnerModel
{
/**
* The <i>current element</i> of the sequence. This element is usually
* displayed by the <code>editor</code> part of a <code>JSpinner</code>.
*
* @return the current spinner value.
* @see #setValue
*/
Object getValue();
/**
* Changes current value of the model, typically this value is displayed
* by the <code>editor</code> part of a <code>JSpinner</code>.
* If the <code>SpinnerModel</code> implementation doesn't support
* the specified value then an <code>IllegalArgumentException</code>
* is thrown. For example a <code>SpinnerModel</code> for numbers might
* only support values that are integer multiples of ten. In
* that case, <code>model.setValue(new Number(11))</code>
* would throw an exception.
*
* @throws IllegalArgumentException if <code>value</code> isn't allowed
* @see #getValue
*/
void setValue(Object value);
/**
* Return the object in the sequence that comes after the object returned
* by <code>getValue()</code>. If the end of the sequence has been reached
* then return null. Calling this method does not effect <code>value</code>.
*
* @return the next legal value or null if one doesn't exist
* @see #getValue
* @see #getPreviousValue
*/
Object getNextValue();
/**
* Return the object in the sequence that comes before the object returned
* by <code>getValue()</code>. If the end of the sequence has been reached then
* return null. Calling this method does not effect <code>value</code>.
*
* @return the previous legal value or null if one doesn't exist
* @see #getValue
* @see #getNextValue
*/
Object getPreviousValue();
/**
* Adds a <code>ChangeListener</code> to the model's listener list. The
* <code>ChangeListeners</code> must be notified when models <code>value</code>
* changes.
*
* @param l the ChangeListener to add
* @see #removeChangeListener
*/
void addChangeListener(ChangeListener l);
/**
* Removes a <code>ChangeListener</code> from the model's listener list.
*
* @param l the ChangeListener to remove
* @see #addChangeListener
*/
void removeChangeListener(ChangeListener l);
}