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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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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,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
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package javax.swing.plaf.nimbus;

import javax.swing.UIManager;
import java.awt.Color;
import java.beans.PropertyChangeSupport;
import java.beans.PropertyChangeListener;


DerivedColor - A color implementation that is derived from a UIManager
defaults table color and a set of offsets. It can be rederived at any point
by calling rederiveColor(). For example when its parent color changes and it
value will update to reflect the new derived color. Property change events
are fired for the "rgb" property when the derived color changes.

Author:Jasper Potts
/**
 * DerivedColor - A color implementation that is derived from a UIManager
 * defaults table color and a set of offsets. It can be rederived at any point
 * by calling rederiveColor(). For example when its parent color changes and it
 * value will update to reflect the new derived color. Property change events
 * are fired for the "rgb" property when the derived color changes.
 *
 * @author Jasper Potts
 */
@SuppressWarnings("serial") // Same-version serialization only
class DerivedColor extends Color {
    private final String uiDefaultParentName;
    private final float hOffset, sOffset, bOffset;
    private final int aOffset;
    private int argbValue;

    DerivedColor(String uiDefaultParentName, float hOffset, float sOffset, float bOffset, int aOffset) {
        super(0);
        this.uiDefaultParentName = uiDefaultParentName;
        this.hOffset = hOffset;
        this.sOffset = sOffset;
        this.bOffset = bOffset;
        this.aOffset = aOffset;
    }

    public String getUiDefaultParentName() {
        return uiDefaultParentName;
    }

    public float getHueOffset() {
        return hOffset;
    }

    public float getSaturationOffset() {
        return sOffset;
    }

    public float getBrightnessOffset() {
        return bOffset;
    }

    public int getAlphaOffset() {
        return aOffset;
    }

    
Recalculate the derived color from the UIManager parent color and offsets

/**
     * Recalculate the derived color from the UIManager parent color and offsets
     */
    public void rederiveColor() {
        Color src = UIManager.getColor(uiDefaultParentName);
        if (src != null) {
            float[] tmp = Color.RGBtoHSB(src.getRed(), src.getGreen(), src.getBlue(), null);
            // apply offsets
            tmp[0] = clamp(tmp[0] + hOffset);
            tmp[1] = clamp(tmp[1] + sOffset);
            tmp[2] = clamp(tmp[2] + bOffset);
            int alpha = clamp(src.getAlpha() + aOffset);
            argbValue = (Color.HSBtoRGB(tmp[0], tmp[1], tmp[2]) & 0xFFFFFF) | (alpha << 24);
        } else {
            float[] tmp = new float[3];
            tmp[0] = clamp(hOffset);
            tmp[1] = clamp(sOffset);
            tmp[2] = clamp(bOffset);
            int alpha = clamp(aOffset);
            argbValue = (Color.HSBtoRGB(tmp[0], tmp[1], tmp[2]) & 0xFFFFFF) | (alpha << 24);
        }
    }

    
Returns the RGB value representing the color in the default sRGB ColorModel. (Bits 24-31 are alpha, 16-23 are red, 8-15 are green, 0-7 are blue). 
See Also:
Returns:the RGB value of the color in the default sRGB ColorModel.
Since:1.0
/**
     * Returns the RGB value representing the color in the default sRGB {@link java.awt.image.ColorModel}. (Bits 24-31
     * are alpha, 16-23 are red, 8-15 are green, 0-7 are blue).
     *
     * @return the RGB value of the color in the default sRGB <code>ColorModel</code>.
     * @see java.awt.image.ColorModel#getRGBdefault
     * @see #getRed
     * @see #getGreen
     * @see #getBlue
     * @since 1.0
     */
    @Override public int getRGB() {
        return argbValue;
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (!(o instanceof DerivedColor)) return false;
        DerivedColor that = (DerivedColor) o;
        if (aOffset != that.aOffset) return false;
        if (Float.compare(that.bOffset, bOffset) != 0) return false;
        if (Float.compare(that.hOffset, hOffset) != 0) return false;
        if (Float.compare(that.sOffset, sOffset) != 0) return false;
        if (!uiDefaultParentName.equals(that.uiDefaultParentName)) return false;
        return true;
    }

    @Override
    public int hashCode() {
        int result = uiDefaultParentName.hashCode();
        result = 31 * result + hOffset != +0.0f ?
                Float.floatToIntBits(hOffset) : 0;
        result = 31 * result + sOffset != +0.0f ?
                Float.floatToIntBits(sOffset) : 0;
        result = 31 * result + bOffset != +0.0f ?
                Float.floatToIntBits(bOffset) : 0;
        result = 31 * result + aOffset;
        return result;
    }

    private float clamp(float value) {
        if (value < 0) {
            value = 0;
        } else if (value > 1) {
            value = 1;
        }
        return value;
    }

    private int clamp(int value) {
        if (value < 0) {
            value = 0;
        } else if (value > 255) {
            value = 255;
        }
        return value;
    }

    
Returns a string representation of this Color. This method
is intended to be used only for debugging purposes. The content and
format of the returned string might vary between implementations. The
returned string might be empty but cannot be null.

Returns:a String representation of this Color.
/**
     * Returns a string representation of this <code>Color</code>. This method
     * is intended to be used only for debugging purposes. The content and
     * format of the returned string might vary between implementations. The
     * returned string might be empty but cannot be <code>null</code>.
     *
     * @return a String representation of this <code>Color</code>.
     */
    @Override
    public String toString() {
        Color src = UIManager.getColor(uiDefaultParentName);
        String s = "DerivedColor(color=" + getRed() + "," + getGreen() + "," + getBlue() +
                " parent=" + uiDefaultParentName +
                " offsets=" + getHueOffset() + "," + getSaturationOffset() + ","
                + getBrightnessOffset() + "," + getAlphaOffset();
        return src == null ? s : s + " pColor=" + src.getRed() + "," + src.getGreen() + "," + src.getBlue();
    }

    @SuppressWarnings("serial") // Same-version serialization only
    static class UIResource extends DerivedColor implements javax.swing.plaf.UIResource {
        UIResource(String uiDefaultParentName, float hOffset, float sOffset,
                   float bOffset, int aOffset) {
            super(uiDefaultParentName, hOffset, sOffset, bOffset, aOffset);
        }

        @Override
        public boolean equals(Object o) {
            return (o instanceof UIResource) && super.equals(o);
        }

        @Override
        public int hashCode() {
            return super.hashCode() + 7;
        }
    }
}