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 * 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,

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 *

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package javax.swing.plaf.synth;

import java.awt.*;

import java.awt.event.*;

import java.beans.*;

import java.util.*;

import javax.swing.*;

import javax.swing.plaf.*;

import javax.swing.plaf.basic.*;

/**

 * Provides the Synth L&F UI delegate for

 * {@link javax.swing.JSplitPane}.

 *

 * @author Scott Violet

 * @since 1.7

 */

public class SynthSplitPaneUI extends BasicSplitPaneUI

                              implements PropertyChangeListener, SynthUI {

    /**

     * Keys to use for forward focus traversal when the JComponent is

     * managing focus.

     */

    private static Set<KeyStroke> managingFocusForwardTraversalKeys;

    /**

     * Keys to use for backward focus traversal when the JComponent is

     * managing focus.

     */

    private static Set<KeyStroke> managingFocusBackwardTraversalKeys;

    /**

     * Style for the JSplitPane.

     */

    private SynthStyle style;

    /**

     * Style for the divider.

     */

    private SynthStyle dividerStyle;

    /**

     * Creates a new SynthSplitPaneUI instance

     *

     * @param x component to create UI object for

     * @return the UI object

     */

    public static ComponentUI createUI(JComponent x) {

        return new SynthSplitPaneUI();

    }

    /**

     * Installs the UI defaults.

     */

    @Override

    protected void installDefaults() {

        updateStyle(splitPane);

        setOrientation(splitPane.getOrientation());

        setContinuousLayout(splitPane.isContinuousLayout());

        resetLayoutManager();

        /* Install the nonContinuousLayoutDivider here to avoid having to

        add/remove everything later. */

        if(nonContinuousLayoutDivider == null) {

            setNonContinuousLayoutDivider(

                                createDefaultNonContinuousLayoutDivider(),

                                true);

        } else {

            setNonContinuousLayoutDivider(nonContinuousLayoutDivider, true);

        }

        // focus forward traversal key

        if (managingFocusForwardTraversalKeys==null) {

            managingFocusForwardTraversalKeys = new HashSet<KeyStroke>();

            managingFocusForwardTraversalKeys.add(

                KeyStroke.getKeyStroke(KeyEvent.VK_TAB, 0));

        }

        splitPane.setFocusTraversalKeys(KeyboardFocusManager.FORWARD_TRAVERSAL_KEYS,

                                        managingFocusForwardTraversalKeys);

        // focus backward traversal key

        if (managingFocusBackwardTraversalKeys==null) {

            managingFocusBackwardTraversalKeys = new HashSet<KeyStroke>();

            managingFocusBackwardTraversalKeys.add(

                KeyStroke.getKeyStroke(KeyEvent.VK_TAB, InputEvent.SHIFT_MASK));

        }

        splitPane.setFocusTraversalKeys(KeyboardFocusManager.BACKWARD_TRAVERSAL_KEYS,

                                        managingFocusBackwardTraversalKeys);

    }

    private void updateStyle(JSplitPane splitPane) {

        SynthContext context = getContext(splitPane, Region.SPLIT_PANE_DIVIDER,

                                          ENABLED);

        SynthStyle oldDividerStyle = dividerStyle;

        dividerStyle = SynthLookAndFeel.updateStyle(context, this);

        context.dispose();

        context = getContext(splitPane, ENABLED);

        SynthStyle oldStyle = style;

        style = SynthLookAndFeel.updateStyle(context, this);

        if (style != oldStyle) {

            Object value = style.get(context, "SplitPane.size");

            if (value == null) {

                value = Integer.valueOf(6);

            }

            LookAndFeel.installProperty(splitPane, "dividerSize", value);

            value = style.get(context, "SplitPane.oneTouchExpandable");

            if (value != null) {

                LookAndFeel.installProperty(splitPane, "oneTouchExpandable", value);

            }

            if (divider != null) {

                splitPane.remove(divider);

                divider.setDividerSize(splitPane.getDividerSize());

            }

            if (oldStyle != null) {

                uninstallKeyboardActions();

                installKeyboardActions();

            }

        }

        if (style != oldStyle || dividerStyle != oldDividerStyle) {

            // Only way to force BasicSplitPaneDivider to reread the

            // necessary properties.

            if (divider != null) {

                splitPane.remove(divider);

            }

            divider = createDefaultDivider();

            divider.setBasicSplitPaneUI(this);

            splitPane.add(divider, JSplitPane.DIVIDER);

        }

        context.dispose();

    }

    /**

     * Installs the event listeners for the UI.

     */

    @Override

    protected void installListeners() {

        super.installListeners();

        splitPane.addPropertyChangeListener(this);

    }

    /**

     * Uninstalls the UI defaults.

     */

    @Override

    protected void uninstallDefaults() {

        SynthContext context = getContext(splitPane, ENABLED);

        style.uninstallDefaults(context);

        context.dispose();

        style = null;

        context = getContext(splitPane, Region.SPLIT_PANE_DIVIDER, ENABLED);

        dividerStyle.uninstallDefaults(context);

        context.dispose();

        dividerStyle = null;

        super.uninstallDefaults();

    }

    /**

     * Uninstalls the event listeners from the UI.

     */

    @Override

    protected void uninstallListeners() {

        super.uninstallListeners();

        splitPane.removePropertyChangeListener(this);

    }

    /**

     * @inheritDoc

     */

    @Override

    public SynthContext getContext(JComponent c) {

        return getContext(c, SynthLookAndFeel.getComponentState(c));

    }

    private SynthContext getContext(JComponent c, int state) {

        return SynthContext.getContext(SynthContext.class, c,

                    SynthLookAndFeel.getRegion(c), style, state);

    }

    SynthContext getContext(JComponent c, Region region) {

        return getContext(c, region, getComponentState(c, region));

    }

    private SynthContext getContext(JComponent c, Region region, int state) {

        if (region == Region.SPLIT_PANE_DIVIDER) {

            return SynthContext.getContext(SynthContext.class, c, region,

                                           dividerStyle, state);

        }

        return SynthContext.getContext(SynthContext.class, c, region,

                                       style, state);

    }

    private int getComponentState(JComponent c, Region subregion) {

        int state = SynthLookAndFeel.getComponentState(c);

        if (divider.isMouseOver()) {

            state |= MOUSE_OVER;

        }

        return state;

    }

    /**

     * @inheritDoc

     */

    @Override

    public void propertyChange(PropertyChangeEvent e) {

        if (SynthLookAndFeel.shouldUpdateStyle(e)) {

            updateStyle((JSplitPane)e.getSource());

        }

    }

    /**

     * Creates the default divider.

     */

    @Override

    public BasicSplitPaneDivider createDefaultDivider() {

        SynthSplitPaneDivider divider = new SynthSplitPaneDivider(this);

        divider.setDividerSize(splitPane.getDividerSize());

        return divider;

    }

    /**

     * @inheritDoc

     */

    @Override

    protected Component createDefaultNonContinuousLayoutDivider() {

        return new Canvas() {

            public void paint(Graphics g) {

                paintDragDivider(g, 0, 0, getWidth(), getHeight());

            }

        };

    }

    /**

     * Notifies this UI delegate to repaint the specified component.

     * This method paints the component background, then calls

     * the {@link #paint(SynthContext,Graphics)} method.

     *

     * <p>In general, this method does not need to be overridden by subclasses.

     * All Look and Feel rendering code should reside in the {@code paint} method.

     *

     * @param g the {@code Graphics} object used for painting

     * @param c the component being painted

     * @see #paint(SynthContext,Graphics)

     */

    @Override

    public void update(Graphics g, JComponent c) {

        SynthContext context = getContext(c);

        SynthLookAndFeel.update(context, g);

        context.getPainter().paintSplitPaneBackground(context,

                          g, 0, 0, c.getWidth(), c.getHeight());

        paint(context, g);

        context.dispose();

    }

    /**

     * Paints the specified component according to the Look and Feel.

     * <p>This method is not used by Synth Look and Feel.

     * Painting is handled by the {@link #paint(SynthContext,Graphics)} method.

     *

     * @param g the {@code Graphics} object used for painting

     * @param c the component being painted

     * @see #paint(SynthContext,Graphics)

     */

    @Override

    public void paint(Graphics g, JComponent c) {

        SynthContext context = getContext(c);

        paint(context, g);

        context.dispose();

    }

    /**

     * Paints the specified component. This implementation does nothing.

     *

     * @param context context for the component being painted

     * @param g the {@code Graphics} object used for painting

     * @see #update(Graphics,JComponent)

     */

    protected void paint(SynthContext context, Graphics g) {

        // This is done to update package private variables in

        // BasicSplitPaneUI

        super.paint(g, splitPane);

    }

    /**

     * @inheritDoc

     */

    @Override

    public void paintBorder(SynthContext context, Graphics g, int x,

                            int y, int w, int h) {

        context.getPainter().paintSplitPaneBorder(context, g, x, y, w, h);

    }

    private void paintDragDivider(Graphics g, int x, int y, int w, int h) {

        SynthContext context = getContext(splitPane,Region.SPLIT_PANE_DIVIDER);

        context.setComponentState(((context.getComponentState() | MOUSE_OVER) ^

                                   MOUSE_OVER) | PRESSED);

        Shape oldClip = g.getClip();

        g.clipRect(x, y, w, h);

        context.getPainter().paintSplitPaneDragDivider(context, g, x, y, w, h,

                                           splitPane.getOrientation());

        g.setClip(oldClip);

        context.dispose();

    }

    /**

     * @inheritDoc

     */

    @Override

    public void finishedPaintingChildren(JSplitPane jc, Graphics g) {

        if(jc == splitPane && getLastDragLocation() != -1 &&

                              !isContinuousLayout() && !draggingHW) {

            if(jc.getOrientation() == JSplitPane.HORIZONTAL_SPLIT) {

                paintDragDivider(g, getLastDragLocation(), 0, dividerSize - 1,

                                 splitPane.getHeight() - 1);

            } else {

                paintDragDivider(g, 0, getLastDragLocation(),

                                 splitPane.getWidth() - 1, dividerSize - 1);

            }

        }

    }

}