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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * under the terms of the GNU General Public License version 2 only, as
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 *
 * 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
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package com.sun.javafx.geom;


A Rectangle specifies an area in a coordinate space that is
enclosed by the Rectangle object's upper-left point (x,y) in the coordinate space, its width, and its height. 

A Rectangle object's width and
height are public fields. The constructors
that create a Rectangle, and the methods that can modify
one, do not prevent setting a negative value for width or height.


 A Rectangle whose width or height is exactly zero has location along those axes with zero dimension, but is otherwise considered empty. The isEmpty method will return true for such a Rectangle. Methods which test if an empty Rectangle contains or intersects a point or rectangle will always return false if either dimension is zero. Methods which combine such a Rectangle with a point or rectangle will include the location of the Rectangle on that axis in the result as if the add(Point) method were being called. 


 A Rectangle whose width or height is negative has neither location nor dimension along those axes with negative dimensions. Such a Rectangle is treated as non-existant along those axes. Such a Rectangle is also empty with respect to containment calculations and methods which test if it contains or intersects a point or rectangle will always return false. Methods which combine such a Rectangle with a point or rectangle will ignore the Rectangle entirely in generating the result. If two Rectangle objects are combined and each has a negative dimension, the result will have at least one negative dimension. 

 Methods which affect only the location of a Rectangle will operate on its location regardless of whether or not it has a negative or zero dimension along either axis. 
 Note that a Rectangle constructed with the default no-argument constructor will have dimensions of 0x0 and therefore be empty. That Rectangle will still have a location of (0,0) and will contribute that location to the union and add operations. Code attempting to accumulate the bounds of a set of points should therefore initially construct the Rectangle with a specifically negative width and height or it should use the first point in the set to construct the Rectangle. For example: 
    Rectangle bounds = new Rectangle(0, 0, -1, -1);
    for (int i = 0; i < points.length; i++) {
        bounds.add(points[i]);
    }


or if we know that the points array contains at least one point:

    Rectangle bounds = new Rectangle(points[0]);
    for (int i = 1; i < points.length; i++) {
        bounds.add(points[i]);
    }



 This class uses 32-bit integers to store its location and dimensions. Frequently operations may produce a result that exceeds the range of a 32-bit integer. The methods will calculate their results in a way that avoids any 32-bit overflow for intermediate results and then choose the best representation to store the final results back into the 32-bit fields which hold the location and dimensions. The location of the result will be stored into the x and y fields by clipping the true result to the nearest 32-bit value. The values stored into the width and height dimension fields will be chosen as the 32-bit values that encompass the largest part of the true result as possible. Generally this means that the dimension will be clipped independently to the range of 32-bit integers except that if the location had to be moved to store it into its pair of 32-bit fields then the dimensions will be adjusted relative to the "best representation" of the location. If the true result had a negative dimension and was therefore non-existant along one or both axes, the stored dimensions will be negative numbers in those axes. If the true result had a location that could be represented within the range of 32-bit integers, but zero dimension along one or both axes, then the stored dimensions will be zero in those axes. 
/**
 * A <code>Rectangle</code> specifies an area in a coordinate space that is
 * enclosed by the <code>Rectangle</code> object's upper-left point
 * {@code (x,y)}
 * in the coordinate space, its width, and its height.
 * <p>
 * A <code>Rectangle</code> object's <code>width</code> and
 * <code>height</code> are <code>public</code> fields. The constructors
 * that create a <code>Rectangle</code>, and the methods that can modify
 * one, do not prevent setting a negative value for width or height.
 * <p>
 * <a name="Empty">
 * A {@code Rectangle} whose width or height is exactly zero has location
 * along those axes with zero dimension, but is otherwise considered empty.
 * The {@link #isEmpty} method will return true for such a {@code Rectangle}.
 * Methods which test if an empty {@code Rectangle} contains or intersects
 * a point or rectangle will always return false if either dimension is zero.
 * Methods which combine such a {@code Rectangle} with a point or rectangle
 * will include the location of the {@code Rectangle} on that axis in the
 * result as if the {@link #add(Point)} method were being called.
 * </a>
 * <p>
 * <a name="NonExistant">
 * A {@code Rectangle} whose width or height is negative has neither
 * location nor dimension along those axes with negative dimensions.
 * Such a {@code Rectangle} is treated as non-existant along those axes.
 * Such a {@code Rectangle} is also empty with respect to containment
 * calculations and methods which test if it contains or intersects a
 * point or rectangle will always return false.
 * Methods which combine such a {@code Rectangle} with a point or rectangle
 * will ignore the {@code Rectangle} entirely in generating the result.
 * If two {@code Rectangle} objects are combined and each has a negative
 * dimension, the result will have at least one negative dimension.
 * </a>
 * <p>
 * Methods which affect only the location of a {@code Rectangle} will
 * operate on its location regardless of whether or not it has a negative
 * or zero dimension along either axis.
 * <p>
 * Note that a {@code Rectangle} constructed with the default no-argument
 * constructor will have dimensions of {@code 0x0} and therefore be empty.
 * That {@code Rectangle} will still have a location of {@code (0,0)} and
 * will contribute that location to the union and add operations.
 * Code attempting to accumulate the bounds of a set of points should
 * therefore initially construct the {@code Rectangle} with a specifically
 * negative width and height or it should use the first point in the set
 * to construct the {@code Rectangle}.
 * For example:
 * <pre>
 *     Rectangle bounds = new Rectangle(0, 0, -1, -1);
 *     for (int i = 0; i < points.length; i++) {
 *         bounds.add(points[i]);
 *     }
 * </pre>
 * or if we know that the points array contains at least one point:
 * <pre>
 *     Rectangle bounds = new Rectangle(points[0]);
 *     for (int i = 1; i < points.length; i++) {
 *         bounds.add(points[i]);
 *     }
 * </pre>
 * <p>
 * This class uses 32-bit integers to store its location and dimensions.
 * Frequently operations may produce a result that exceeds the range of
 * a 32-bit integer.
 * The methods will calculate their results in a way that avoids any
 * 32-bit overflow for intermediate results and then choose the best
 * representation to store the final results back into the 32-bit fields
 * which hold the location and dimensions.
 * The location of the result will be stored into the {@link #x} and
 * {@link #y} fields by clipping the true result to the nearest 32-bit value.
 * The values stored into the {@link #width} and {@link #height} dimension
 * fields will be chosen as the 32-bit values that encompass the largest
 * part of the true result as possible.
 * Generally this means that the dimension will be clipped independently
 * to the range of 32-bit integers except that if the location had to be
 * moved to store it into its pair of 32-bit fields then the dimensions
 * will be adjusted relative to the "best representation" of the location.
 * If the true result had a negative dimension and was therefore
 * non-existant along one or both axes, the stored dimensions will be
 * negative numbers in those axes.
 * If the true result had a location that could be represented within
 * the range of 32-bit integers, but zero dimension along one or both
 * axes, then the stored dimensions will be zero in those axes.
 */
public class Rectangle {

    
The X coordinate of the upper-left corner of the Rectangle.

/**
     * The X coordinate of the upper-left corner of the <code>Rectangle</code>.
     */
    public int x;

    
The Y coordinate of the upper-left corner of the Rectangle.

/**
     * The Y coordinate of the upper-left corner of the <code>Rectangle</code>.
     */
    public int y;

    
The width of the Rectangle.

/**
     * The width of the <code>Rectangle</code>.
     */
    public int width;

    
The height of the Rectangle.

/**
     * The height of the <code>Rectangle</code>.
     */
    public int height;

    
Constructs a new Rectangle whose upper-left corner
is at (0, 0) in the coordinate space, and whose width and
height are both zero.

/**
     * Constructs a new <code>Rectangle</code> whose upper-left corner
     * is at (0,&nbsp;0) in the coordinate space, and whose width and
     * height are both zero.
     */
    public Rectangle() {
        this(0, 0, 0, 0);
    }

    
Constructs a new Rectangle, initialized to match
the values of the specified Rectangle.

Params:
  • r –  the Rectangle from which to copy initial values
          to a newly constructed Rectangle
/**
     * Constructs a new <code>Rectangle</code>, initialized to match
     * the values of the specified <code>Rectangle</code>.
     * @param r  the <code>Rectangle</code> from which to copy initial values
     *           to a newly constructed <code>Rectangle</code>
     */
    public Rectangle(BaseBounds b) {
        setBounds(b);
    }

    
Constructs a new Rectangle, initialized to match
the values of the specified BaseBounds. Since BaseBounds has
float values, the Rectangle will be created such that the bounding rectangle
of the specified BaseBounds would always lie within the bounding box
specified by this Rectangle.

Params:
  • r –  the BaseBounds from which to copy initial values
          to a newly constructed Rectangle
/**
     * Constructs a new <code>Rectangle</code>, initialized to match
     * the values of the specified <code>BaseBounds</code>. Since BaseBounds has
     * float values, the Rectangle will be created such that the bounding rectangle
     * of the specified BaseBounds would always lie within the bounding box
     * specified by this Rectangle.
     * @param r  the <code>BaseBounds</code> from which to copy initial values
     *           to a newly constructed <code>Rectangle</code>
     */
    public Rectangle(Rectangle r) {
        this(r.x, r.y, r.width, r.height);
    }

    
Constructs a new Rectangle whose upper-left corner is specified as (x,y) and whose width and height are specified by the arguments of the same name. 
Params:
  • x – the specified X coordinate
  • y – the specified Y coordinate
  • width –    the width of the Rectangle
  • height –   the height of the Rectangle
/**
     * Constructs a new <code>Rectangle</code> whose upper-left corner is
     * specified as
     * {@code (x,y)} and whose width and height
     * are specified by the arguments of the same name.
     * @param     x the specified X coordinate
     * @param     y the specified Y coordinate
     * @param     width    the width of the <code>Rectangle</code>
     * @param     height   the height of the <code>Rectangle</code>
     */
    public Rectangle(int x, int y, int width, int height) {
        this.x = x;
        this.y = y;
        this.width = width;
        this.height = height;
    }

    
Constructs a new Rectangle whose upper-left corner
is at (0, 0) in the coordinate space, and whose width and
height are specified by the arguments of the same name.

Params:
  • width – the width of the Rectangle
  • height – the height of the Rectangle
/**
     * Constructs a new <code>Rectangle</code> whose upper-left corner
     * is at (0,&nbsp;0) in the coordinate space, and whose width and
     * height are specified by the arguments of the same name.
     * @param width the width of the <code>Rectangle</code>
     * @param height the height of the <code>Rectangle</code>
     */
    public Rectangle(int width, int height) {
        this(0, 0, width, height);
    }

    
Sets the bounding Rectangle of this Rectangle
to match the specified Rectangle.


This method is included for completeness, to parallel the
setBounds method of Component.

Params:
  • r – the specified Rectangle
See Also:
/**
     * Sets the bounding <code>Rectangle</code> of this <code>Rectangle</code>
     * to match the specified <code>Rectangle</code>.
     * <p>
     * This method is included for completeness, to parallel the
     * <code>setBounds</code> method of <code>Component</code>.
     * @param r the specified <code>Rectangle</code>
     * @see       #getBounds
     * @see       java.awt.Component#setBounds(java.awt.Rectangle)
     */
    public void setBounds(Rectangle r) {
        setBounds(r.x, r.y, r.width, r.height);
    }

    
Sets the bounding Rectangle of this
Rectangle to the specified
x, y, width,
and height.


This method is included for completeness, to parallel the
setBounds method of Component.

Params:
  • x – the new X coordinate for the upper-left
                   corner of this Rectangle
  • y – the new Y coordinate for the upper-left
                   corner of this Rectangle
  • width – the new width for this Rectangle
  • height – the new height for this Rectangle
See Also:
/**
     * Sets the bounding <code>Rectangle</code> of this
     * <code>Rectangle</code> to the specified
     * <code>x</code>, <code>y</code>, <code>width</code>,
     * and <code>height</code>.
     * <p>
     * This method is included for completeness, to parallel the
     * <code>setBounds</code> method of <code>Component</code>.
     * @param x the new X coordinate for the upper-left
     *                    corner of this <code>Rectangle</code>
     * @param y the new Y coordinate for the upper-left
     *                    corner of this <code>Rectangle</code>
     * @param width the new width for this <code>Rectangle</code>
     * @param height the new height for this <code>Rectangle</code>
     * @see       #getBounds
     * @see       java.awt.Component#setBounds(int, int, int, int)
     */
    public void setBounds(int x, int y, int width, int height) {
        reshape(x, y, width, height);
    }

    public void setBounds(BaseBounds b) {
        x = (int) Math.floor(b.getMinX());
        y = (int) Math.floor(b.getMinY());
        int x2 = (int) Math.ceil(b.getMaxX());
        int y2 = (int) Math.ceil(b.getMaxY());
        width = x2 - x;
        height = y2 - y;
    }

    
Checks whether or not this Rectangle contains the point at the specified location (cx,cy). 
Params:
  • cx – the specified X coordinate
  • cy – the specified Y coordinate
Returns:   true if the point (cx,cy) is inside this Rectangle;
           false otherwise.
/**
     * Checks whether or not this <code>Rectangle</code> contains the
     * point at the specified location {@code (cx,cy)}.
     *
     * @param cx the specified X coordinate
     * @param cy the specified Y coordinate
     * @return    <code>true</code> if the point
     *            {@code (cx,cy)} is inside this
     *            <code>Rectangle</code>;
     *            <code>false</code> otherwise.
     */
    public boolean contains(int cx, int cy) {
        int tw = this.width;
        int th = this.height;
        if ((tw | th) < 0) {
            // At least one of the dimensions is negative...
            return false;
        }
        // Note: if either dimension is zero, tests below must return false...
        int tx = this.x;
        int ty = this.y;
        if (cx < tx || cy < ty) {
            return false;
        }
        tw += tx;
        th += ty;
        //    overflow || intersect
        return ((tw < tx || tw > cx) &&
                (th < ty || th > cy));
     }

    
Checks whether or not this Rectangle entirely contains
the specified Rectangle.

Params:
  • r –   the specified Rectangle
Returns:   true if the Rectangle
           is contained entirely inside this Rectangle;
           false otherwise
/**
     * Checks whether or not this <code>Rectangle</code> entirely contains
     * the specified <code>Rectangle</code>.
     *
     * @param     r   the specified <code>Rectangle</code>
     * @return    <code>true</code> if the <code>Rectangle</code>
     *            is contained entirely inside this <code>Rectangle</code>;
     *            <code>false</code> otherwise
     */
    public boolean contains(Rectangle r) {
        return contains(r.x, r.y, r.width, r.height);
    }

    
Checks whether this Rectangle entirely contains
the Rectangle at the specified location (cx,cy) with the specified dimensions (cw,ch). 
Params:
  • cx – the specified X coordinate
  • cy – the specified Y coordinate
  • cw –   the width of the Rectangle
  • ch –   the height of the Rectangle
Returns:   true if the Rectangle specified by (cx, cy, cw, ch) is entirely enclosed inside this Rectangle;
           false otherwise.
/**
     * Checks whether this <code>Rectangle</code> entirely contains
     * the <code>Rectangle</code>
     * at the specified location {@code (cx,cy)} with the
     * specified dimensions {@code (cw,ch)}.
     * @param     cx the specified X coordinate
     * @param     cy the specified Y coordinate
     * @param     cw   the width of the <code>Rectangle</code>
     * @param     ch   the height of the <code>Rectangle</code>
     * @return    <code>true</code> if the <code>Rectangle</code> specified by
     *            {@code (cx, cy, cw, ch)}
     *            is entirely enclosed inside this <code>Rectangle</code>;
     *            <code>false</code> otherwise.
     */
    public boolean contains(int cx, int cy, int cw, int ch) {
        int tw = this.width;
        int th = this.height;
        if ((tw | th | cw | ch) < 0) {
            // At least one of the dimensions is negative...
            return false;
        }
        // Note: if any dimension is zero, tests below must return false...
        int tx = this.x;
        int ty = this.y;
        if (cx < tx || cy < ty) {
            return false;
        }
        tw += tx;
        cw += cx;
        if (cw <= cx) {
            // cx+cw overflowed or cw was zero, return false if...
            // either original tw or cw was zero or
            // tx+tw did not overflow or
            // the overflowed cx+cw is smaller than the overflowed tx+tw
            if (tw >= tx || cw > tw) return false;
        } else {
            // cx+cw did not overflow and cw was not zero, return false if...
            // original tw was zero or
            // tx+tw did not overflow and tx+tw is smaller than cx+cw
            if (tw >= tx && cw > tw) return false;
        }
        th += ty;
        ch += cy;
        if (ch <= cy) {
            if (th >= ty || ch > th) return false;
        } else {
            if (th >= ty && ch > th) return false;
        }
        return true;
    }

    public Rectangle intersection(Rectangle r) {
        Rectangle ret = new Rectangle(this);
        ret.intersectWith(r);
        return ret;
    }

    public void intersectWith(Rectangle r) {
        if (r == null) {
            return;
        }
        int tx1 = this.x;
        int ty1 = this.y;
        int rx1 = r.x;
        int ry1 = r.y;
        long tx2 = tx1; tx2 += this.width;
        long ty2 = ty1; ty2 += this.height;
        long rx2 = rx1; rx2 += r.width;
        long ry2 = ry1; ry2 += r.height;
        if (tx1 < rx1) tx1 = rx1;
        if (ty1 < ry1) ty1 = ry1;
        if (tx2 > rx2) tx2 = rx2;
        if (ty2 > ry2) ty2 = ry2;
        tx2 -= tx1;
        ty2 -= ty1;
        // tx2,ty2 will never overflow (they will never be
        // larger than the smallest of the two source w,h)
        // they might underflow, though...
        if (tx2 < Integer.MIN_VALUE) tx2 = Integer.MIN_VALUE;
        if (ty2 < Integer.MIN_VALUE) ty2 = Integer.MIN_VALUE;
        setBounds(tx1, ty1, (int) tx2, (int) ty2);
    }

    
Translates this Rectangle the indicated distance,
to the right along the X coordinate axis, and
downward along the Y coordinate axis.

Params:
  • dx – the distance to move this Rectangle
                along the X axis
  • dy – the distance to move this Rectangle
                along the Y axis
See Also:
/**
     * Translates this <code>Rectangle</code> the indicated distance,
     * to the right along the X coordinate axis, and
     * downward along the Y coordinate axis.
     * @param dx the distance to move this <code>Rectangle</code>
     *                 along the X axis
     * @param dy the distance to move this <code>Rectangle</code>
     *                 along the Y axis
     * @see       java.awt.Rectangle#setLocation(int, int)
     * @see       java.awt.Rectangle#setLocation(java.awt.Point)
     */
    public void translate(int dx, int dy) {
        int oldv = this.x;
        int newv = oldv + dx;
        if (dx < 0) {
            // moving leftward
            if (newv > oldv) {
                // negative overflow
                // Only adjust width if it was valid (>= 0).
                if (width >= 0) {
                    // The right edge is now conceptually at
                    // newv+width, but we may move newv to prevent
                    // overflow.  But we want the right edge to
                    // remain at its new location in spite of the
                    // clipping.  Think of the following adjustment
                    // conceptually the same as:
                    // width += newv; newv = MIN_VALUE; width -= newv;
                    width += newv - Integer.MIN_VALUE;
                    // width may go negative if the right edge went past
                    // MIN_VALUE, but it cannot overflow since it cannot
                    // have moved more than MIN_VALUE and any non-negative
                    // number + MIN_VALUE does not overflow.
                }
                newv = Integer.MIN_VALUE;
            }
        } else {
            // moving rightward (or staying still)
            if (newv < oldv) {
                // positive overflow
                if (width >= 0) {
                    // Conceptually the same as:
                    // width += newv; newv = MAX_VALUE; width -= newv;
                    width += newv - Integer.MAX_VALUE;
                    // With large widths and large displacements
                    // we may overflow so we need to check it.
                    if (width < 0) width = Integer.MAX_VALUE;
                }
                newv = Integer.MAX_VALUE;
            }
        }
        this.x = newv;

        oldv = this.y;
        newv = oldv + dy;
        if (dy < 0) {
            // moving upward
            if (newv > oldv) {
                // negative overflow
                if (height >= 0) {
                    height += newv - Integer.MIN_VALUE;
                    // See above comment about no overflow in this case
                }
                newv = Integer.MIN_VALUE;
            }
        } else {
            // moving downward (or staying still)
            if (newv < oldv) {
                // positive overflow
                if (height >= 0) {
                    height += newv - Integer.MAX_VALUE;
                    if (height < 0) height = Integer.MAX_VALUE;
                }
                newv = Integer.MAX_VALUE;
            }
        }
        this.y = newv;
    }

    public RectBounds toRectBounds() {
        return new RectBounds(x, y, x+width, y+height);
    }

    
Adds a point, specified by the integer arguments newx,newy to the bounds of this Rectangle. 
 If this Rectangle has any dimension less than zero, the rules for non-existant rectangles apply. In that case, the new bounds of this Rectangle will have a location equal to the specified coordinates and width and height equal to zero. 

After adding a point, a call to contains with the
added point as an argument does not necessarily return
true. The contains method does not
return true for points on the right or bottom
edges of a Rectangle. Therefore, if the added point
falls on the right or bottom edge of the enlarged
Rectangle, contains returns
false for that point. If the specified point must be contained within the new Rectangle, a 1x1 rectangle should be added instead: 
    r.add(newx, newy, 1, 1);



Params:
  • newx – the X coordinate of the new point
  • newy – the Y coordinate of the new point
/**
     * Adds a point, specified by the integer arguments {@code newx,newy}
     * to the bounds of this {@code Rectangle}.
     * <p>
     * If this {@code Rectangle} has any dimension less than zero,
     * the rules for <a href=#NonExistant>non-existant</a>
     * rectangles apply.
     * In that case, the new bounds of this {@code Rectangle} will
     * have a location equal to the specified coordinates and
     * width and height equal to zero.
     * <p>
     * After adding a point, a call to <code>contains</code> with the
     * added point as an argument does not necessarily return
     * <code>true</code>. The <code>contains</code> method does not
     * return <code>true</code> for points on the right or bottom
     * edges of a <code>Rectangle</code>. Therefore, if the added point
     * falls on the right or bottom edge of the enlarged
     * <code>Rectangle</code>, <code>contains</code> returns
     * <code>false</code> for that point.
     * If the specified point must be contained within the new
     * {@code Rectangle}, a 1x1 rectangle should be added instead:
     * <pre>
     *     r.add(newx, newy, 1, 1);
     * </pre>
     * @param newx the X coordinate of the new point
     * @param newy the Y coordinate of the new point
     */
    public void add(int newx, int newy) {
        if ((width | height) < 0) {
            this.x = newx;
            this.y = newy;
            this.width = this.height = 0;
            return;
        }
        int x1 = this.x;
        int y1 = this.y;
        long x2 = this.width;
        long y2 = this.height;
        x2 += x1;
        y2 += y1;
        if (x1 > newx) x1 = newx;
        if (y1 > newy) y1 = newy;
        if (x2 < newx) x2 = newx;
        if (y2 < newy) y2 = newy;
        x2 -= x1;
        y2 -= y1;
        if (x2 > Integer.MAX_VALUE) x2 = Integer.MAX_VALUE;
        if (y2 > Integer.MAX_VALUE) y2 = Integer.MAX_VALUE;
        reshape(x1, y1, (int) x2, (int) y2);
    }

    
Adds a Rectangle to this Rectangle.
The resulting Rectangle is the union of the two
rectangles.

 If either Rectangle has any dimension less than 0, the result will have the dimensions of the other Rectangle. If both Rectangles have at least one dimension less than 0, the result will have at least one dimension less than 0. 
 If either Rectangle has one or both dimensions equal to 0, the result along those axes with 0 dimensions will be equivalent to the results obtained by adding the corresponding origin coordinate to the result rectangle along that axis, similar to the operation of the add(Point) method, but contribute no further dimension beyond that. 
 If the resulting Rectangle would have a dimension too large to be expressed as an int, the result will have a dimension of Integer.MAX_VALUE along that dimension. 
Params:
  • r – the specified Rectangle
/**
     * Adds a <code>Rectangle</code> to this <code>Rectangle</code>.
     * The resulting <code>Rectangle</code> is the union of the two
     * rectangles.
     * <p>
     * If either {@code Rectangle} has any dimension less than 0, the
     * result will have the dimensions of the other {@code Rectangle}.
     * If both {@code Rectangle}s have at least one dimension less
     * than 0, the result will have at least one dimension less than 0.
     * <p>
     * If either {@code Rectangle} has one or both dimensions equal
     * to 0, the result along those axes with 0 dimensions will be
     * equivalent to the results obtained by adding the corresponding
     * origin coordinate to the result rectangle along that axis,
     * similar to the operation of the {@link #add(Point)} method,
     * but contribute no further dimension beyond that.
     * <p>
     * If the resulting {@code Rectangle} would have a dimension
     * too large to be expressed as an {@code int}, the result
     * will have a dimension of {@code Integer.MAX_VALUE} along
     * that dimension.
     * @param  r the specified <code>Rectangle</code>
     */
    public void add(Rectangle r) {
        long tx2 = this.width;
        long ty2 = this.height;
        if ((tx2 | ty2) < 0) {
            reshape(r.x, r.y, r.width, r.height);
        }
        long rx2 = r.width;
        long ry2 = r.height;
        if ((rx2 | ry2) < 0) {
            return;
        }
        int tx1 = this.x;
        int ty1 = this.y;
        tx2 += tx1;
        ty2 += ty1;
        int rx1 = r.x;
        int ry1 = r.y;
        rx2 += rx1;
        ry2 += ry1;
        if (tx1 > rx1) tx1 = rx1;
        if (ty1 > ry1) ty1 = ry1;
        if (tx2 < rx2) tx2 = rx2;
        if (ty2 < ry2) ty2 = ry2;
        tx2 -= tx1;
        ty2 -= ty1;
        // tx2,ty2 will never underflow since both original
        // rectangles were non-empty
        // they might overflow, though...
        if (tx2 > Integer.MAX_VALUE) tx2 = Integer.MAX_VALUE;
        if (ty2 > Integer.MAX_VALUE) ty2 = Integer.MAX_VALUE;
        reshape(tx1, ty1, (int) tx2, (int) ty2);
    }

    
Resizes the Rectangle both horizontally and vertically.


This method modifies the Rectangle so that it is
h units larger on both the left and right side,
and v units larger at both the top and bottom.


The new Rectangle has (x - h, y - v) as its upper-left corner, width of (width + 2h), and a height of (height + 2v). 

If negative values are supplied for h and
v, the size of the Rectangle decreases accordingly. The grow method will check for integer overflow and underflow, but does not check whether the resulting values of width and height grow from negative to non-negative or shrink from non-negative to negative. 
Params:
  • h – the horizontal expansion
  • v – the vertical expansion
/**
     * Resizes the <code>Rectangle</code> both horizontally and vertically.
     * <p>
     * This method modifies the <code>Rectangle</code> so that it is
     * <code>h</code> units larger on both the left and right side,
     * and <code>v</code> units larger at both the top and bottom.
     * <p>
     * The new <code>Rectangle</code> has {@code (x - h, y - v)}
     * as its upper-left corner,
     * width of {@code (width + 2h)},
     * and a height of {@code (height + 2v)}.
     * <p>
     * If negative values are supplied for <code>h</code> and
     * <code>v</code>, the size of the <code>Rectangle</code>
     * decreases accordingly.
     * The {@code grow} method will check for integer overflow
     * and underflow, but does not check whether the resulting
     * values of {@code width} and {@code height} grow
     * from negative to non-negative or shrink from non-negative
     * to negative.
     * @param h the horizontal expansion
     * @param v the vertical expansion
     */
    public void grow(int h, int v) {
        long x0 = this.x;
        long y0 = this.y;
        long x1 = this.width;
        long y1 = this.height;
        x1 += x0;
        y1 += y0;

        x0 -= h;
        y0 -= v;
        x1 += h;
        y1 += v;

        if (x1 < x0) {
            // Non-existant in X direction
            // Final width must remain negative so subtract x0 before
            // it is clipped so that we avoid the risk that the clipping
            // of x0 will reverse the ordering of x0 and x1.
            x1 -= x0;
            if (x1 < Integer.MIN_VALUE) x1 = Integer.MIN_VALUE;
            if (x0 < Integer.MIN_VALUE) x0 = Integer.MIN_VALUE;
            else if (x0 > Integer.MAX_VALUE) x0 = Integer.MAX_VALUE;
        } else { // (x1 >= x0)
            // Clip x0 before we subtract it from x1 in case the clipping
            // affects the representable area of the rectangle.
            if (x0 < Integer.MIN_VALUE) x0 = Integer.MIN_VALUE;
            else if (x0 > Integer.MAX_VALUE) x0 = Integer.MAX_VALUE;
            x1 -= x0;
            // The only way x1 can be negative now is if we clipped
            // x0 against MIN and x1 is less than MIN - in which case
            // we want to leave the width negative since the result
            // did not intersect the representable area.
            if (x1 < Integer.MIN_VALUE) x1 = Integer.MIN_VALUE;
            else if (x1 > Integer.MAX_VALUE) x1 = Integer.MAX_VALUE;
        }

        if (y1 < y0) {
            // Non-existant in Y direction
            y1 -= y0;
            if (y1 < Integer.MIN_VALUE) y1 = Integer.MIN_VALUE;
            if (y0 < Integer.MIN_VALUE) y0 = Integer.MIN_VALUE;
            else if (y0 > Integer.MAX_VALUE) y0 = Integer.MAX_VALUE;
        } else { // (y1 >= y0)
            if (y0 < Integer.MIN_VALUE) y0 = Integer.MIN_VALUE;
            else if (y0 > Integer.MAX_VALUE) y0 = Integer.MAX_VALUE;
            y1 -= y0;
            if (y1 < Integer.MIN_VALUE) y1 = Integer.MIN_VALUE;
            else if (y1 > Integer.MAX_VALUE) y1 = Integer.MAX_VALUE;
        }

        reshape((int) x0, (int) y0, (int) x1, (int) y1);
    }

    private void reshape(int x, int y, int width, int height) {
        this.x = x;
        this.y = y;
        this.width = width;
        this.height = height;
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    public boolean isEmpty() {
        return (width <= 0) || (height <= 0);
    }

    
Checks whether two rectangles are equal.


The result is true if and only if the argument is not
null and is a Rectangle object that has the
same upper-left corner, width, and height as
this Rectangle.

Params:
  • obj – the Object to compare with
               this Rectangle
Returns:   true if the objects are equal;
           false otherwise.
/**
     * Checks whether two rectangles are equal.
     * <p>
     * The result is <code>true</code> if and only if the argument is not
     * <code>null</code> and is a <code>Rectangle</code> object that has the
     * same upper-left corner, width, and height as
     * this <code>Rectangle</code>.
     * @param obj the <code>Object</code> to compare with
     *                this <code>Rectangle</code>
     * @return    <code>true</code> if the objects are equal;
     *            <code>false</code> otherwise.
     */
    @Override
    public boolean equals(Object obj) {
        if (obj instanceof Rectangle) {
            Rectangle r = (Rectangle)obj;
            return ((x == r.x) &&
                    (y == r.y) &&
                    (width == r.width) &&
                    (height == r.height));
        }
        return super.equals(obj);
    }

    @Override
    public int hashCode() {
        int bits = java.lang.Float.floatToIntBits(x);
        bits += java.lang.Float.floatToIntBits(y) * 37;
        bits += java.lang.Float.floatToIntBits(width) * 43;
        bits += java.lang.Float.floatToIntBits(height) * 47;
        return bits;
    }

    
Returns a String representing this
Rectangle and its values.

Returns:a String representing this
              Rectangle object's coordinate and size values.
/**
     * Returns a <code>String</code> representing this
     * <code>Rectangle</code> and its values.
     * @return a <code>String</code> representing this
     *               <code>Rectangle</code> object's coordinate and size values.
     */
    @Override
    public String toString() {
        return getClass().getName() + "[x=" + x + ",y=" + y + ",width=" + width + ",height=" + height + "]";
    }
}