/*

 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * 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).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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 * questions.

 */

package javax.swing;

import javax.swing.plaf.*;

import javax.accessibility.*;

import java.io.ObjectOutputStream;

import java.io.ObjectInputStream;

import java.io.IOException;

/**

 * <code>JSeparator</code> provides a general purpose component for

 * implementing divider lines - most commonly used as a divider

 * between menu items that breaks them up into logical groupings.

 * Instead of using <code>JSeparator</code> directly,

 * you can use the <code>JMenu</code> or <code>JPopupMenu</code>

 * <code>addSeparator</code> method to create and add a separator.

 * <code>JSeparator</code>s may also be used elsewhere in a GUI

 * wherever a visual divider is useful.

 *

 * <p>

 *

 * For more information and examples see

 * <a

 href="http://docs.oracle.com/javase/tutorial/uiswing/components/menu.html">How to Use Menus</a>,

 * a section in <em>The Java Tutorial.</em>

 * <p>

 * <strong>Warning:</strong> Swing is not thread safe. For more

 * information see <a

 * href="package-summary.html#threading">Swing's Threading

 * Policy</a>.

 * <p>

 * <strong>Warning:</strong>

 * Serialized objects of this class will not be compatible with

 * future Swing releases. The current serialization support is

 * appropriate for short term storage or RMI between applications running

 * the same version of Swing.  As of 1.4, support for long term storage

 * of all JavaBeans™

 * has been added to the <code>java.beans</code> package.

 * Please see {@link java.beans.XMLEncoder}.

 *

 * @beaninfo

 *      attribute: isContainer false

 *    description: A divider between menu items.

 *

 * @author Georges Saab

 * @author Jeff Shapiro

 */

@SuppressWarnings("serial")

public class JSeparator extends JComponent implements SwingConstants, Accessible

{

    /**

     * @see #getUIClassID

     * @see #readObject

     */

    private static final String uiClassID = "SeparatorUI";

    private int orientation = HORIZONTAL;

    /** Creates a new horizontal separator. */

    public JSeparator()

    {

        this( HORIZONTAL );

    }

    /**

     * Creates a new separator with the specified horizontal or

     * vertical orientation.

     *

     * @param orientation an integer specifying

     *          <code>SwingConstants.HORIZONTAL</code> or

     *          <code>SwingConstants.VERTICAL</code>

     * @exception IllegalArgumentException if <code>orientation</code>

     *          is neither <code>SwingConstants.HORIZONTAL</code> nor

     *          <code>SwingConstants.VERTICAL</code>

     */

    public JSeparator( int orientation )

    {

        checkOrientation( orientation );

        this.orientation = orientation;

        setFocusable(false);

        updateUI();

    }

    /**

     * Returns the L&F object that renders this component.

     *

     * @return the SeparatorUI object that renders this component

     */

    public SeparatorUI getUI() {

        return (SeparatorUI)ui;

    }

    /**

     * Sets the L&F object that renders this component.

     *

     * @param ui  the SeparatorUI L&F object

     * @see UIDefaults#getUI

     * @beaninfo

     *        bound: true

     *       hidden: true

     *    attribute: visualUpdate true

     *  description: The UI object that implements the Component's LookAndFeel.

     */

    public void setUI(SeparatorUI ui) {

        super.setUI(ui);

    }

    /**

     * Resets the UI property to a value from the current look and feel.

     *

     * @see JComponent#updateUI

     */

    public void updateUI() {

        setUI((SeparatorUI)UIManager.getUI(this));

    }

    /**

     * Returns the name of the L&F class that renders this component.

     *

     * @return the string "SeparatorUI"

     * @see JComponent#getUIClassID

     * @see UIDefaults#getUI

     */

    public String getUIClassID() {

        return uiClassID;

    }

    /**

     * See <code>readObject</code> and <code>writeObject</code> in

     * <code>JComponent</code> for more

     * information about serialization in Swing.

     */

    private void writeObject(ObjectOutputStream s) throws IOException {

        s.defaultWriteObject();

        if (getUIClassID().equals(uiClassID)) {

            byte count = JComponent.getWriteObjCounter(this);

            JComponent.setWriteObjCounter(this, --count);

            if (count == 0 && ui != null) {

                ui.installUI(this);

            }

        }

    }

    /**

     * Returns the orientation of this separator.

     *

     * @return   The value of the orientation property, one of the

     *           following constants defined in <code>SwingConstants</code>:

     *           <code>VERTICAL</code>, or

     *           <code>HORIZONTAL</code>.

     *

     * @see SwingConstants

     * @see #setOrientation

     */

    public int getOrientation() {

        return this.orientation;

    }

    /**

     * Sets the orientation of the separator.

     * The default value of this property is HORIZONTAL.

     * @param orientation  either <code>SwingConstants.HORIZONTAL</code>

     *                  or <code>SwingConstants.VERTICAL</code>

     * @exception IllegalArgumentException  if <code>orientation</code>

     *          is neither <code>SwingConstants.HORIZONTAL</code>

     *          nor <code>SwingConstants.VERTICAL</code>

     *

     * @see SwingConstants

     * @see #getOrientation

     * @beaninfo

     *        bound: true

     *    preferred: true

     *         enum: HORIZONTAL SwingConstants.HORIZONTAL

     *               VERTICAL   SwingConstants.VERTICAL

     *    attribute: visualUpdate true

     *  description: The orientation of the separator.

     */

    public void setOrientation( int orientation ) {

        if (this.orientation == orientation) {

            return;

        }

        int oldValue = this.orientation;

        checkOrientation( orientation );

        this.orientation = orientation;

        firePropertyChange("orientation", oldValue, orientation);

        revalidate();

        repaint();

    }

    private void checkOrientation( int orientation )

    {

        switch ( orientation )

        {

            case VERTICAL:

            case HORIZONTAL:

                break;

            default:

                throw new IllegalArgumentException( "orientation must be one of: VERTICAL, HORIZONTAL" );

        }

    }

    /**

     * Returns a string representation of this <code>JSeparator</code>.

     * This method

     * is intended to be used only for debugging purposes, and the

     * content and format of the returned string may vary between

     * implementations. The returned string may be empty but may not

     * be <code>null</code>.

     *

     * @return  a string representation of this <code>JSeparator</code>

     */

    protected String paramString() {

        String orientationString = (orientation == HORIZONTAL ?

                                    "HORIZONTAL" : "VERTICAL");

        return super.paramString() +

        ",orientation=" + orientationString;

    }

/////////////////

// Accessibility support

////////////////

    /**

     * Gets the AccessibleContext associated with this JSeparator.

     * For separators, the AccessibleContext takes the form of an

     * AccessibleJSeparator.

     * A new AccessibleJSeparator instance is created if necessary.

     *

     * @return an AccessibleJSeparator that serves as the

     *         AccessibleContext of this JSeparator

     */

    public AccessibleContext getAccessibleContext() {

        if (accessibleContext == null) {

            accessibleContext = new AccessibleJSeparator();

        }

        return accessibleContext;

    }

    /**

     * This class implements accessibility support for the

     * <code>JSeparator</code> class.  It provides an implementation of the

     * Java Accessibility API appropriate to separator user-interface elements.

     * <p>

     * <strong>Warning:</strong>

     * Serialized objects of this class will not be compatible with

     * future Swing releases. The current serialization support is

     * appropriate for short term storage or RMI between applications running

     * the same version of Swing.  As of 1.4, support for long term storage

     * of all JavaBeans™

     * has been added to the <code>java.beans</code> package.

     * Please see {@link java.beans.XMLEncoder}.

     */

    @SuppressWarnings("serial")

    protected class AccessibleJSeparator extends AccessibleJComponent {

        /**

         * Get the role of this object.

         *

         * @return an instance of AccessibleRole describing the role of the

         * object

         */

        public AccessibleRole getAccessibleRole() {

            return AccessibleRole.SEPARATOR;

        }

    }

}