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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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package java.awt.geom;

import java.io.Serializable;


The Ellipse2D class describes an ellipse that is defined by a framing rectangle. 

This class is only the abstract superclass for all objects which
store a 2D ellipse.
The actual storage representation of the coordinates is left to
the subclass.

Author:     Jim Graham
Since:1.2
/**
 * The {@code Ellipse2D} class describes an ellipse that is defined
 * by a framing rectangle.
 * <p>
 * This class is only the abstract superclass for all objects which
 * store a 2D ellipse.
 * The actual storage representation of the coordinates is left to
 * the subclass.
 *
 * @author      Jim Graham
 * @since 1.2
 */
public abstract class Ellipse2D extends RectangularShape {

    
The Float class defines an ellipse specified in float precision. 
Since:1.2
/**
     * The {@code Float} class defines an ellipse specified
     * in {@code float} precision.
     * @since 1.2
     */
    public static class Float extends Ellipse2D implements Serializable {
        
The X coordinate of the upper-left corner of the framing rectangle of this Ellipse2D. 
Since:1.2
@serial
/**
         * The X coordinate of the upper-left corner of the
         * framing rectangle of this {@code Ellipse2D}.
         * @since 1.2
         * @serial
         */
        public float x;

        
The Y coordinate of the upper-left corner of the framing rectangle of this Ellipse2D. 
Since:1.2
@serial
/**
         * The Y coordinate of the upper-left corner of the
         * framing rectangle of this {@code Ellipse2D}.
         * @since 1.2
         * @serial
         */
        public float y;

        
The overall width of this Ellipse2D. 
Since:1.2
@serial
/**
         * The overall width of this {@code Ellipse2D}.
         * @since 1.2
         * @serial
         */
        public float width;

        
The overall height of this Ellipse2D. 
Since:1.2
@serial
/**
         * The overall height of this {@code Ellipse2D}.
         * @since 1.2
         * @serial
         */
        public float height;

        
Constructs a new Ellipse2D, initialized to location (0, 0) and size (0, 0). 
Since:1.2
/**
         * Constructs a new {@code Ellipse2D}, initialized to
         * location (0,&nbsp;0) and size (0,&nbsp;0).
         * @since 1.2
         */
        public Float() {
        }

        
Constructs and initializes an Ellipse2D from the specified coordinates. 
Params:
  • x – the X coordinate of the upper-left corner
         of the framing rectangle
  • y – the Y coordinate of the upper-left corner
         of the framing rectangle
  • w – the width of the framing rectangle
  • h – the height of the framing rectangle
Since:1.2
/**
         * Constructs and initializes an {@code Ellipse2D} from the
         * specified coordinates.
         *
         * @param x the X coordinate of the upper-left corner
         *          of the framing rectangle
         * @param y the Y coordinate of the upper-left corner
         *          of the framing rectangle
         * @param w the width of the framing rectangle
         * @param h the height of the framing rectangle
         * @since 1.2
         */
        public Float(float x, float y, float w, float h) {
            setFrame(x, y, w, h);
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public double getX() {
            return (double) x;
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public double getY() {
            return (double) y;
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public double getWidth() {
            return (double) width;
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public double getHeight() {
            return (double) height;
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public boolean isEmpty() {
            return (width <= 0.0 || height <= 0.0);
        }

        
Sets the location and size of the framing rectangle of this Shape to the specified rectangular values. 
Params:
  • x – the X coordinate of the upper-left corner of the
             specified rectangular shape
  • y – the Y coordinate of the upper-left corner of the
             specified rectangular shape
  • w – the width of the specified rectangular shape
  • h – the height of the specified rectangular shape
Since:1.2
/**
         * Sets the location and size of the framing rectangle of this
         * {@code Shape} to the specified rectangular values.
         *
         * @param x the X coordinate of the upper-left corner of the
         *              specified rectangular shape
         * @param y the Y coordinate of the upper-left corner of the
         *              specified rectangular shape
         * @param w the width of the specified rectangular shape
         * @param h the height of the specified rectangular shape
         * @since 1.2
         */
        public void setFrame(float x, float y, float w, float h) {
            this.x = x;
            this.y = y;
            this.width = w;
            this.height = h;
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public void setFrame(double x, double y, double w, double h) {
            this.x = (float) x;
            this.y = (float) y;
            this.width = (float) w;
            this.height = (float) h;
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public Rectangle2D getBounds2D() {
            return new Rectangle2D.Float(x, y, width, height);
        }

        /*
         * JDK 1.6 serialVersionUID
         */
        private static final long serialVersionUID = -6633761252372475977L;
    }

    
The Double class defines an ellipse specified in double precision. 
Since:1.2
/**
     * The {@code Double} class defines an ellipse specified
     * in {@code double} precision.
     * @since 1.2
     */
    public static class Double extends Ellipse2D implements Serializable {
        
The X coordinate of the upper-left corner of the framing rectangle of this Ellipse2D. 
Since:1.2
@serial
/**
         * The X coordinate of the upper-left corner of the
         * framing rectangle of this {@code Ellipse2D}.
         * @since 1.2
         * @serial
         */
        public double x;

        
The Y coordinate of the upper-left corner of the framing rectangle of this Ellipse2D. 
Since:1.2
@serial
/**
         * The Y coordinate of the upper-left corner of the
         * framing rectangle of this {@code Ellipse2D}.
         * @since 1.2
         * @serial
         */
        public double y;

        
The overall width of this Ellipse2D. 
Since:1.2
@serial
/**
         * The overall width of this {@code Ellipse2D}.
         * @since 1.2
         * @serial
         */
        public double width;

        
The overall height of the Ellipse2D. 
Since:1.2
@serial
/**
         * The overall height of the {@code Ellipse2D}.
         * @since 1.2
         * @serial
         */
        public double height;

        
Constructs a new Ellipse2D, initialized to location (0, 0) and size (0, 0). 
Since:1.2
/**
         * Constructs a new {@code Ellipse2D}, initialized to
         * location (0,&nbsp;0) and size (0,&nbsp;0).
         * @since 1.2
         */
        public Double() {
        }

        
Constructs and initializes an Ellipse2D from the specified coordinates. 
Params:
  • x – the X coordinate of the upper-left corner
       of the framing rectangle
  • y – the Y coordinate of the upper-left corner
       of the framing rectangle
  • w – the width of the framing rectangle
  • h – the height of the framing rectangle
Since:1.2
/**
         * Constructs and initializes an {@code Ellipse2D} from the
         * specified coordinates.
         *
         * @param x the X coordinate of the upper-left corner
         *        of the framing rectangle
         * @param y the Y coordinate of the upper-left corner
         *        of the framing rectangle
         * @param w the width of the framing rectangle
         * @param h the height of the framing rectangle
         * @since 1.2
         */
        public Double(double x, double y, double w, double h) {
            setFrame(x, y, w, h);
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public double getX() {
            return x;
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public double getY() {
            return y;
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public double getWidth() {
            return width;
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public double getHeight() {
            return height;
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public boolean isEmpty() {
            return (width <= 0.0 || height <= 0.0);
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public void setFrame(double x, double y, double w, double h) {
            this.x = x;
            this.y = y;
            this.width = w;
            this.height = h;
        }

        
{@inheritDoc}

Since:1.2
/**
         * {@inheritDoc}
         * @since 1.2
         */
        public Rectangle2D getBounds2D() {
            return new Rectangle2D.Double(x, y, width, height);
        }

        /*
         * JDK 1.6 serialVersionUID
         */
        private static final long serialVersionUID = 5555464816372320683L;
    }

    
This is an abstract class that cannot be instantiated directly.
Type-specific implementation subclasses are available for
instantiation and provide a number of formats for storing
the information necessary to satisfy the various accessor
methods below.

See Also:
Since:1.2
/**
     * This is an abstract class that cannot be instantiated directly.
     * Type-specific implementation subclasses are available for
     * instantiation and provide a number of formats for storing
     * the information necessary to satisfy the various accessor
     * methods below.
     *
     * @see java.awt.geom.Ellipse2D.Float
     * @see java.awt.geom.Ellipse2D.Double
     * @since 1.2
     */
    protected Ellipse2D() {
    }

    
{@inheritDoc}

Since:1.2
/**
     * {@inheritDoc}
     * @since 1.2
     */
    public boolean contains(double x, double y) {
        // Normalize the coordinates compared to the ellipse
        // having a center at 0,0 and a radius of 0.5.
        double ellw = getWidth();
        if (ellw <= 0.0) {
            return false;
        }
        double normx = (x - getX()) / ellw - 0.5;
        double ellh = getHeight();
        if (ellh <= 0.0) {
            return false;
        }
        double normy = (y - getY()) / ellh - 0.5;
        return (normx * normx + normy * normy) < 0.25;
    }

    
{@inheritDoc}

Since:1.2
/**
     * {@inheritDoc}
     * @since 1.2
     */
    public boolean intersects(double x, double y, double w, double h) {
        if (w <= 0.0 || h <= 0.0) {
            return false;
        }
        // Normalize the rectangular coordinates compared to the ellipse
        // having a center at 0,0 and a radius of 0.5.
        double ellw = getWidth();
        if (ellw <= 0.0) {
            return false;
        }
        double normx0 = (x - getX()) / ellw - 0.5;
        double normx1 = normx0 + w / ellw;
        double ellh = getHeight();
        if (ellh <= 0.0) {
            return false;
        }
        double normy0 = (y - getY()) / ellh - 0.5;
        double normy1 = normy0 + h / ellh;
        // find nearest x (left edge, right edge, 0.0)
        // find nearest y (top edge, bottom edge, 0.0)
        // if nearest x,y is inside circle of radius 0.5, then intersects
        double nearx, neary;
        if (normx0 > 0.0) {
            // center to left of X extents
            nearx = normx0;
        } else if (normx1 < 0.0) {
            // center to right of X extents
            nearx = normx1;
        } else {
            nearx = 0.0;
        }
        if (normy0 > 0.0) {
            // center above Y extents
            neary = normy0;
        } else if (normy1 < 0.0) {
            // center below Y extents
            neary = normy1;
        } else {
            neary = 0.0;
        }
        return (nearx * nearx + neary * neary) < 0.25;
    }

    
{@inheritDoc}

Since:1.2
/**
     * {@inheritDoc}
     * @since 1.2
     */
    public boolean contains(double x, double y, double w, double h) {
        return (contains(x, y) &&
                contains(x + w, y) &&
                contains(x, y + h) &&
                contains(x + w, y + h));
    }

    
Returns an iteration object that defines the boundary of this Ellipse2D. The iterator for this class is multi-threaded safe, which means that this Ellipse2D class guarantees that modifications to the geometry of this Ellipse2D object do not affect any iterations of that geometry that are already in process. 
Params:
  • at – an optional AffineTransform to be applied to the coordinates as they are returned in the iteration, or null if untransformed coordinates are desired
Returns: the PathIterator object that returns the geometry of the outline of this Ellipse2D, one segment at a time.
Since:1.2
/**
     * Returns an iteration object that defines the boundary of this
     * {@code Ellipse2D}.
     * The iterator for this class is multi-threaded safe, which means
     * that this {@code Ellipse2D} class guarantees that
     * modifications to the geometry of this {@code Ellipse2D}
     * object do not affect any iterations of that geometry that
     * are already in process.
     * @param at an optional {@code AffineTransform} to be applied to
     * the coordinates as they are returned in the iteration, or
     * {@code null} if untransformed coordinates are desired
     * @return    the {@code PathIterator} object that returns the
     *          geometry of the outline of this {@code Ellipse2D},
     *          one segment at a time.
     * @since 1.2
     */
    public PathIterator getPathIterator(AffineTransform at) {
        return new EllipseIterator(this, at);
    }

    
Returns the hashcode for this Ellipse2D. 
Returns:the hashcode for this Ellipse2D.
Since:1.6
/**
     * Returns the hashcode for this {@code Ellipse2D}.
     * @return the hashcode for this {@code Ellipse2D}.
     * @since 1.6
     */
    public int hashCode() {
        long bits = java.lang.Double.doubleToLongBits(getX());
        bits += java.lang.Double.doubleToLongBits(getY()) * 37;
        bits += java.lang.Double.doubleToLongBits(getWidth()) * 43;
        bits += java.lang.Double.doubleToLongBits(getHeight()) * 47;
        return (((int) bits) ^ ((int) (bits >> 32)));
    }

    
Determines whether or not the specified Object is equal to this Ellipse2D. The specified Object is equal to this Ellipse2D if it is an instance of Ellipse2D and if its location and size are the same as this Ellipse2D. 
Params:
  • obj –  an Object to be compared with this Ellipse2D.
Returns: true if obj is an instance of Ellipse2D and has the same values; false otherwise.
Since:1.6
/**
     * Determines whether or not the specified {@code Object} is
     * equal to this {@code Ellipse2D}.  The specified
     * {@code Object} is equal to this {@code Ellipse2D}
     * if it is an instance of {@code Ellipse2D} and if its
     * location and size are the same as this {@code Ellipse2D}.
     * @param obj  an {@code Object} to be compared with this
     *             {@code Ellipse2D}.
     * @return  {@code true} if {@code obj} is an instance
     *          of {@code Ellipse2D} and has the same values;
     *          {@code false} otherwise.
     * @since 1.6
     */
    public boolean equals(Object obj) {
        if (obj == this) {
            return true;
        }
        if (obj instanceof Ellipse2D) {
            Ellipse2D e2d = (Ellipse2D) obj;
            return ((getX() == e2d.getX()) &&
                    (getY() == e2d.getY()) &&
                    (getWidth() == e2d.getWidth()) &&
                    (getHeight() == e2d.getHeight()));
        }
        return false;
    }
}