bldcomponent.java

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/*
 * Copyright (c) 1995 - 2008 Sun Microsystems, Inc.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   - Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   - Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *
 *   - Neither the name of Sun Microsystems nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */ 

package layout;

/*
 * Used by BoxLayoutDemo.java.
*/

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

/** A rectangle that has a fixed size. */
class BLDComponent extends JComponent
                   implements MouseListener {
    private Color normalHue;
    private final Dimension preferredSize;
    private String name;
    private boolean restrictMaximumSize;
    private boolean printSize;

    public BLDComponent(float alignmentX, float hue,
                        int shortSideSize,
                        boolean restrictSize,
                        boolean printSize,
                        String name) {
        this.name = name;
        this.restrictMaximumSize = restrictSize;
        this.printSize = printSize;
        setAlignmentX(alignmentX);
        normalHue = Color.getHSBColor(hue, 0.4f, 0.85f);
        preferredSize = new Dimension(shortSideSize*2,
                                      shortSideSize);

        addMouseListener(this);
    }

    //The MouseListener interface requires that we define
    //mousePressed, mouseReleased, mouseEntered, mouseExited,
    //and mouseClicked.
    public void mousePressed(MouseEvent e) {
        int width = getWidth();
        float alignment = (float)(e.getX())
                        / (float)width;

        // Round to the nearest 1/10th.
        int tmp = Math.round(alignment * 10.0f);
        alignment = (float)tmp / 10.0f;

        setAlignmentX(alignment);
        revalidate(); // this GUI needs relayout
        repaint();
    }
    public void mouseReleased(MouseEvent e) { }
    public void mouseEntered(MouseEvent e) { }
    public void mouseExited(MouseEvent e) { }
    public void mouseClicked(MouseEvent e) { }

    /**
     * Our BLDComponents are completely opaque, so we override
     * this method to return true.  This lets the painting
     * system know that it doesn't need to paint any covered
     * part of the components underneath this component.  The
     * end result is possibly improved painting performance.
     */
    public boolean isOpaque() {
        return true;
    }

    public void paint(Graphics g) {
        int width = getWidth();
        int height = getHeight();
        float alignmentX = getAlignmentX();

        g.setColor(normalHue);
        g.fill3DRect(0, 0, width, height, true);

        /* Draw a vertical white line at the alignment point.*/
        // XXX: This code is probably not the best.
        g.setColor(Color.white);
        int x = (int)(alignmentX * (float)width) - 1;
        g.drawLine(x, 0, x, height - 1);

        /* Say what the alignment point is. */
        g.setColor(Color.black);
        g.drawString(Float.toString(alignmentX), 3, height - 3);

        if (printSize) {
            System.out.println("BLDComponent " + name + ": size is "
                               + width + "x" + height
                               + "; preferred size is "
                               + getPreferredSize().width + "x"
                               + getPreferredSize().height);
        }
    }

    public Dimension getPreferredSize() {
        return preferredSize;
    }

    public Dimension getMinimumSize() {
        return preferredSize;
    }

    public Dimension getMaximumSize() {
        if (restrictMaximumSize) {
            return preferredSize;
        } else {
            return super.getMaximumSize();
        }
    }

    public void setSizeRestriction(boolean restrictSize) {
        restrictMaximumSize = restrictSize;
    }
}