/*
 * Copyright (c) 2008, 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 javafx.geometry;

import javafx.beans.NamedArg;


/**
 * A 2D dimension object that contains a width and a height.
 *
 * @since JavaFX 2.0
 */
public class Dimension2D {
    /**
     * Constructs a <code>Dimension2D</code> with the specified width and
     * height.
     *
     * @param width the width
     * @param height the height
     */
    public Dimension2D(@NamedArg("width") double width, @NamedArg("height") double height) {
        this.width = width;
        this.height = height;
    }
    
    /**
     * The width of the dimension.
     *
     * @defaultValue 0.0
     */
    private double width;

    /**
     * The width of the dimension.
     * @return the width of the dimension
     */
    public final double getWidth() {
        return width;
    }
    
    /**
     * The height of the dimension.
     *
     * @defaultValue 0.0
     */
    private double height;

    /**
     * The height of the dimension.
     * @return the height of the dimension
     */
    public final double getHeight() {
        return height;
    }

    /**
     * Cache the hash code to make computing hashes faster.
     */
    private int hash = 0;

    /**
     * Indicates whether some other object is "equal to" this one.
     * 
     * @param obj the reference object with which to compare
     * @return true if this Dimension2D instance is the same as the obj argument; false otherwise
     */
    @Override public boolean equals(Object obj) {
        if (obj == this) return true;
        if (obj instanceof Dimension2D) {
            Dimension2D other = (Dimension2D) obj;
            return getWidth() == other.getWidth() && getHeight() == other.getHeight();
        } else return false;
    }

    /**
     * Returns a hash code value for the Dimension2D object.
     * @return a hash code value for the Dimension2D object.
     */
    @Override public int hashCode() {
        if (hash == 0) {
            long bits = 7L;
            bits = 31L * bits + Double.doubleToLongBits(getWidth());
            bits = 31L * bits + Double.doubleToLongBits(getHeight());
	    hash = (int) (bits ^ (bits >> 32));
        }
        return hash;
    }

    /**
     * Returns a string representation of this {@code Dimension2D}.
     * This method is intended to be used only for informational purposes.
     * The content and format of the returned string might vary between
     * implementations.
     * The returned string might be empty but cannot be {@code null}.
     */
    @Override public String toString() {
        return "Dimension2D [width = " + getWidth() + ", height = " + getHeight() + "]";
    }
}
