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/*
 * Copyright (c) 1998, 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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package javax.swing.colorchooser;

import javax.swing.*;
import javax.swing.border.*;
import javax.swing.event.*;
import javax.swing.text.*;
import java.awt.*;
import java.awt.image.*;
import java.awt.event.*;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.io.Serializable;
import sun.swing.SwingUtilities2;



The standard preview panel for the color chooser.


Warning:
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 java.beans package. Please see XMLEncoder. 
Author:Steve Wilson
See Also:
/**
 * The standard preview panel for the color chooser.
 * <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&trade;
 * has been added to the <code>java.beans</code> package.
 * Please see {@link java.beans.XMLEncoder}.
 *
 * @author Steve Wilson
 * @see JColorChooser
 */
class DefaultPreviewPanel extends JPanel {

    private int squareSize = 25;
    private int squareGap = 5;
    private int innerGap = 5;


    private int textGap = 5;
    private Font font = new Font(Font.DIALOG, Font.PLAIN, 12);
    private String sampleText;

    private int swatchWidth = 50;

    private Color oldColor = null;

    private JColorChooser getColorChooser() {
        return (JColorChooser)SwingUtilities.getAncestorOfClass(
                                   JColorChooser.class, this);
    }

    public Dimension getPreferredSize() {
        JComponent host = getColorChooser();
        if (host == null) {
            host = this;
        }
        FontMetrics fm = host.getFontMetrics(getFont());

        int ascent = fm.getAscent();
        int height = fm.getHeight();
        int width = SwingUtilities2.stringWidth(host, fm, getSampleText());

        int y = height*3 + textGap*3;
        int x = squareSize * 3 + squareGap*2 + swatchWidth + width + textGap*3;
        return new Dimension( x,y );
    }

    public void paintComponent(Graphics g) {
        if (oldColor == null)
            oldColor = getForeground();

        g.setColor(getBackground());
        g.fillRect(0,0,getWidth(),getHeight());

        if (this.getComponentOrientation().isLeftToRight()) {
            int squareWidth = paintSquares(g, 0);
            int textWidth = paintText(g, squareWidth);
            paintSwatch(g, squareWidth + textWidth);
        } else {
            int swatchWidth = paintSwatch(g, 0);
            int textWidth = paintText(g, swatchWidth);
            paintSquares(g , swatchWidth + textWidth);

        }
    }

    private int paintSwatch(Graphics g, int offsetX) {
        int swatchX = offsetX;
        g.setColor(oldColor);
        g.fillRect(swatchX, 0, swatchWidth, (squareSize) + (squareGap/2));
        g.setColor(getForeground());
        g.fillRect(swatchX, (squareSize) + (squareGap/2), swatchWidth, (squareSize) + (squareGap/2) );
        return (swatchX+swatchWidth);
    }

    private int paintText(Graphics g, int offsetX) {
        g.setFont(getFont());
        JComponent host = getColorChooser();
        if (host == null) {
            host = this;
        }
        FontMetrics fm = SwingUtilities2.getFontMetrics(host, g);

        int ascent = fm.getAscent();
        int height = fm.getHeight();
        int width = SwingUtilities2.stringWidth(host, fm, getSampleText());

        int textXOffset = offsetX + textGap;

        Color color = getForeground();

        g.setColor(color);

        SwingUtilities2.drawString(host, g, getSampleText(),textXOffset+(textGap/2),
                                   ascent+2);

        g.fillRect(textXOffset,
                   ( height) + textGap,
                   width + (textGap),
                   height +2);

        g.setColor(Color.black);
        SwingUtilities2.drawString(host, g, getSampleText(),
                     textXOffset+(textGap/2),
                     height+ascent+textGap+2);


        g.setColor(Color.white);

        g.fillRect(textXOffset,
                   ( height + textGap) * 2,
                   width + (textGap),
                   height +2);

        g.setColor(color);
        SwingUtilities2.drawString(host, g, getSampleText(),
                     textXOffset+(textGap/2),
                     ((height+textGap) * 2)+ascent+2);

        return width + textGap*3;

    }

    private int paintSquares(Graphics g, int offsetX) {

        int squareXOffset = offsetX;
        Color color = getForeground();

        g.setColor(Color.white);
        g.fillRect(squareXOffset,0,squareSize,squareSize);
        g.setColor(color);
        g.fillRect(squareXOffset+innerGap,
                   innerGap,
                   squareSize - (innerGap*2),
                   squareSize - (innerGap*2));
        g.setColor(Color.white);
        g.fillRect(squareXOffset+innerGap*2,
                   innerGap*2,
                   squareSize - (innerGap*4),
                   squareSize - (innerGap*4));

        g.setColor(color);
        g.fillRect(squareXOffset,squareSize+squareGap,squareSize,squareSize);

        g.translate(squareSize+squareGap, 0);
        g.setColor(Color.black);
        g.fillRect(squareXOffset,0,squareSize,squareSize);
        g.setColor(color);
        g.fillRect(squareXOffset+innerGap,
                   innerGap,
                   squareSize - (innerGap*2),
                   squareSize - (innerGap*2));
        g.setColor(Color.white);
        g.fillRect(squareXOffset+innerGap*2,
                   innerGap*2,
                   squareSize - (innerGap*4),
                   squareSize - (innerGap*4));
        g.translate(-(squareSize+squareGap), 0);

        g.translate(squareSize+squareGap, squareSize+squareGap);
        g.setColor(Color.white);
        g.fillRect(squareXOffset,0,squareSize,squareSize);
        g.setColor(color);
        g.fillRect(squareXOffset+innerGap,
                   innerGap,
                   squareSize - (innerGap*2),
                   squareSize - (innerGap*2));
        g.translate(-(squareSize+squareGap), -(squareSize+squareGap));



        g.translate((squareSize+squareGap)*2, 0);
        g.setColor(Color.white);
        g.fillRect(squareXOffset,0,squareSize,squareSize);
        g.setColor(color);
        g.fillRect(squareXOffset+innerGap,
                   innerGap,
                   squareSize - (innerGap*2),
                   squareSize - (innerGap*2));
        g.setColor(Color.black);
        g.fillRect(squareXOffset+innerGap*2,
                   innerGap*2,
                   squareSize - (innerGap*4),
                   squareSize - (innerGap*4));
        g.translate(-((squareSize+squareGap)*2), 0);

        g.translate((squareSize+squareGap)*2, (squareSize+squareGap));
        g.setColor(Color.black);
        g.fillRect(squareXOffset,0,squareSize,squareSize);
        g.setColor(color);
        g.fillRect(squareXOffset+innerGap,
                   innerGap,
                   squareSize - (innerGap*2),
                   squareSize - (innerGap*2));
        g.translate(-((squareSize+squareGap)*2), -(squareSize+squareGap));

        return (squareSize*3+squareGap*2);

    }

    private String getSampleText() {
        if (this.sampleText == null) {
            this.sampleText = UIManager.getString("ColorChooser.sampleText", getLocale());
        }
        return this.sampleText;
    }
}