Module java.desktop

Package java.awt.geom

Class Rectangle2D

java.lang.Object

java.awt.geom.RectangularShape

java.awt.geom.Rectangle2D

All Implemented Interfaces:

Shape, Cloneable

Direct Known Subclasses:

Rectangle, Rectangle2D.Double, Rectangle2D.Float

public abstract class Rectangle2D
extends RectangularShape

The Rectangle2D class describes a rectangle defined by a location (x,y) and dimension (w x h).

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

Since:

1.2

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	Rectangle2D.Double	The Double class defines a rectangle specified in double coordinates.
static class	Rectangle2D.Float	The Float class defines a rectangle specified in float coordinates.

Field Summary

Fields

Modifier and Type	Field	Description
static int	OUT_BOTTOM	The bitmask that indicates that a point lies below this Rectangle2D.
static int	OUT_LEFT	The bitmask that indicates that a point lies to the left of this Rectangle2D.
static int	OUT_RIGHT	The bitmask that indicates that a point lies to the right of this Rectangle2D.
static int	OUT_TOP	The bitmask that indicates that a point lies above this Rectangle2D.

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	Rectangle2D()	This is an abstract class that cannot be instantiated directly.

Method Summary

Modifier and Type	Method	Description
void	add(double newx, double newy)	Adds a point, specified by the double precision arguments newx and newy, to this Rectangle2D.
void	add(Point2D pt)	Adds the Point2D object pt to this Rectangle2D.
void	add(Rectangle2D r)	Adds a Rectangle2D object to this Rectangle2D.
boolean	contains(double x, double y)	Tests if the specified coordinates are inside the boundary of the Shape, as described by the definition of insideness.
boolean	contains(double x, double y, double w, double h)	Tests if the interior of the Shape entirely contains the specified rectangular area.
abstract Rectangle2D	createIntersection(Rectangle2D r)	Returns a new Rectangle2D object representing the intersection of this Rectangle2D with the specified Rectangle2D.
abstract Rectangle2D	createUnion(Rectangle2D r)	Returns a new Rectangle2D object representing the union of this Rectangle2D with the specified Rectangle2D.
boolean	equals(Object obj)	Determines whether or not the specified Object is equal to this Rectangle2D.
Rectangle2D	getBounds2D()	Returns a high precision and more accurate bounding box of the Shape than the getBounds method.
PathIterator	getPathIterator(AffineTransform at)	Returns an iteration object that defines the boundary of this Rectangle2D.
PathIterator	getPathIterator(AffineTransform at, double flatness)	Returns an iteration object that defines the boundary of the flattened Rectangle2D.
int	hashCode()	Returns the hashcode for this Rectangle2D.
static void	intersect(Rectangle2D src1, Rectangle2D src2, Rectangle2D dest)	Intersects the pair of specified source Rectangle2D objects and puts the result into the specified destination Rectangle2D object.
boolean	intersects(double x, double y, double w, double h)	Tests if the interior of the Shape intersects the interior of a specified rectangular area.
boolean	intersectsLine(double x1, double y1, double x2, double y2)	Tests if the specified line segment intersects the interior of this Rectangle2D.
boolean	intersectsLine(Line2D l)	Tests if the specified line segment intersects the interior of this Rectangle2D.
abstract int	outcode(double x, double y)	Determines where the specified coordinates lie with respect to this Rectangle2D.
int	outcode(Point2D p)	Determines where the specified Point2D lies with respect to this Rectangle2D.
void	setFrame(double x, double y, double w, double h)	Sets the location and size of the outer bounds of this Rectangle2D to the specified rectangular values.
abstract void	setRect(double x, double y, double w, double h)	Sets the location and size of this Rectangle2D to the specified double values.
void	setRect(Rectangle2D r)	Sets this Rectangle2D to be the same as the specified Rectangle2D.
static void	union(Rectangle2D src1, Rectangle2D src2, Rectangle2D dest)	Unions the pair of source Rectangle2D objects and puts the result into the specified destination Rectangle2D object.

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Methods inherited from class java.awt.geom.RectangularShape

clone, contains, contains, getBounds, getCenterX, getCenterY, getFrame, getHeight, getMaxX, getMaxY, getMinX, getMinY, getWidth, getX, getY, intersects, isEmpty, setFrame, setFrame, setFrameFromCenter, setFrameFromCenter, setFrameFromDiagonal, setFrameFromDiagonal

Field Detail

OUT_LEFT

public static final int OUT_LEFT

The bitmask that indicates that a point lies to the left of this Rectangle2D.

Since:

1.2

See Also:

Constant Field Values

OUT_TOP

public static final int OUT_TOP

The bitmask that indicates that a point lies above this Rectangle2D.

Since:

1.2

See Also:

Constant Field Values

OUT_RIGHT

public static final int OUT_RIGHT

The bitmask that indicates that a point lies to the right of this Rectangle2D.

Since:

1.2

See Also:

Constant Field Values

OUT_BOTTOM

public static final int OUT_BOTTOM

The bitmask that indicates that a point lies below this Rectangle2D.

Since:

1.2

See Also:

Constant Field Values

Constructor Detail

Rectangle2D

protected Rectangle2D()

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.

Since:

1.2

See Also:

Rectangle2D.Float, Rectangle2D.Double, Rectangle

Method Detail

setRect

public abstract void setRect(double x,
                             double y,
                             double w,
                             double h)

Sets the location and size of this Rectangle2D to the specified double values.

Parameters:

x - the X coordinate of the upper-left corner of this Rectangle2D

y - the Y coordinate of the upper-left corner of this Rectangle2D

w - the width of this Rectangle2D

h - the height of this Rectangle2D

Since:

1.2

setRect

public void setRect(Rectangle2D r)

Sets this Rectangle2D to be the same as the specified Rectangle2D.

Parameters:

r - the specified Rectangle2D

Since:

1.2

intersectsLine

public boolean intersectsLine(double x1,
                              double y1,
                              double x2,
                              double y2)

Tests if the specified line segment intersects the interior of this Rectangle2D.

Parameters:

x1 - the X coordinate of the start point of the specified line segment

y1 - the Y coordinate of the start point of the specified line segment

x2 - the X coordinate of the end point of the specified line segment

y2 - the Y coordinate of the end point of the specified line segment

Returns:

true if the specified line segment intersects the interior of this Rectangle2D; false otherwise.

Since:

1.2

intersectsLine

public boolean intersectsLine(Line2D l)

Tests if the specified line segment intersects the interior of this Rectangle2D.

Parameters:

l - the specified Line2D to test for intersection with the interior of this Rectangle2D

Returns:

true if the specified Line2D intersects the interior of this Rectangle2D; false otherwise.

Since:

1.2

outcode

public abstract int outcode(double x,
                            double y)

Determines where the specified coordinates lie with respect to this Rectangle2D. This method computes a binary OR of the appropriate mask values indicating, for each side of this Rectangle2D, whether or not the specified coordinates are on the same side of the edge as the rest of this Rectangle2D.

Parameters:

x - the specified X coordinate

y - the specified Y coordinate

Returns:

the logical OR of all appropriate out codes.

Since:

1.2

See Also:

OUT_LEFT, OUT_TOP, OUT_RIGHT, OUT_BOTTOM

outcode

public int outcode(Point2D p)

Determines where the specified Point2D lies with respect to this Rectangle2D. This method computes a binary OR of the appropriate mask values indicating, for each side of this Rectangle2D, whether or not the specified Point2D is on the same side of the edge as the rest of this Rectangle2D.

Parameters:

p - the specified Point2D

Returns:

the logical OR of all appropriate out codes.

Since:

1.2

See Also:

OUT_LEFT, OUT_TOP, OUT_RIGHT, OUT_BOTTOM

setFrame

public void setFrame(double x,
                     double y,
                     double w,
                     double h)

Sets the location and size of the outer bounds of this Rectangle2D to the specified rectangular values.

Specified by:

setFrame in class RectangularShape

Parameters:

x - the X coordinate of the upper-left corner of this Rectangle2D

y - the Y coordinate of the upper-left corner of this Rectangle2D

w - the width of this Rectangle2D

h - the height of this Rectangle2D

Since:

1.2

See Also:

RectangularShape.getFrame()

getBounds2D

public Rectangle2D getBounds2D()

Returns a high precision and more accurate bounding box of the Shape than the getBounds method. Note that there is no guarantee that the returned Rectangle2D is the smallest bounding box that encloses the Shape, only that the Shape lies entirely within the indicated Rectangle2D. The bounding box returned by this method is usually tighter than that returned by the getBounds method and never fails due to overflow problems since the return value can be an instance of the Rectangle2D that uses double precision values to store the dimensions.

Note that the definition of insideness can lead to situations where points on the defining outline of the shape may not be considered contained in the returned bounds object, but only in cases where those points are also not considered contained in the original shape.

If a point is inside the shape according to the contains(point) method, then it must be inside the returned Rectangle2D bounds object according to the contains(point) method of the bounds. Specifically:

shape.contains(p) requires bounds.contains(p)

If a point is not inside the shape, then it might still be contained in the bounds object:

bounds.contains(p) does not imply shape.contains(p)

Returns:

an instance of Rectangle2D that is a high-precision bounding box of the Shape.

Since:

1.2

See Also:

Shape.getBounds()

contains

public boolean contains(double x,
                        double y)

Tests if the specified coordinates are inside the boundary of the Shape, as described by the definition of insideness.

Parameters:

x - the specified X coordinate to be tested

y - the specified Y coordinate to be tested

Returns:

true if the specified coordinates are inside the Shape boundary; false otherwise.

Since:

1.2

intersects

public boolean intersects(double x,
                          double y,
                          double w,
                          double h)

Tests if the interior of the Shape intersects the interior of a specified rectangular area. The rectangular area is considered to intersect the Shape if any point is contained in both the interior of the Shape and the specified rectangular area.

The Shape.intersects() method allows a Shape implementation to conservatively return true when:

• there is a high probability that the rectangular area and the Shape intersect, but
• the calculations to accurately determine this intersection are prohibitively expensive.

This means that for some Shapes this method might return true even though the rectangular area does not intersect the Shape. The Area class performs more accurate computations of geometric intersection than most Shape objects and therefore can be used if a more precise answer is required.

Parameters:

x - the X coordinate of the upper-left corner of the specified rectangular area

y - the Y coordinate of the upper-left corner of the specified rectangular area

w - the width of the specified rectangular area

h - the height of the specified rectangular area

Returns:

true if the interior of the Shape and the interior of the rectangular area intersect, or are both highly likely to intersect and intersection calculations would be too expensive to perform; false otherwise.

Since:

1.2

See Also:

Area

contains

public boolean contains(double x,
                        double y,
                        double w,
                        double h)

Tests if the interior of the Shape entirely contains the specified rectangular area. All coordinates that lie inside the rectangular area must lie within the Shape for the entire rectangular area to be considered contained within the Shape.

The Shape.contains() method allows a Shape implementation to conservatively return false when:

• the intersect method returns true and
• the calculations to determine whether or not the Shape entirely contains the rectangular area are prohibitively expensive.

This means that for some Shapes this method might return false even though the Shape contains the rectangular area. The Area class performs more accurate geometric computations than most Shape objects and therefore can be used if a more precise answer is required.

Parameters:

x - the X coordinate of the upper-left corner of the specified rectangular area

y - the Y coordinate of the upper-left corner of the specified rectangular area

w - the width of the specified rectangular area

h - the height of the specified rectangular area

Returns:

true if the interior of the Shape entirely contains the specified rectangular area; false otherwise or, if the Shape contains the rectangular area and the intersects method returns true and the containment calculations would be too expensive to perform.

Since:

1.2

See Also:

Area, Shape.intersects(double, double, double, double)

createIntersection

public abstract Rectangle2D createIntersection(Rectangle2D r)

Returns a new Rectangle2D object representing the intersection of this Rectangle2D with the specified Rectangle2D.

Parameters:

r - the Rectangle2D to be intersected with this Rectangle2D

Returns:

the largest Rectangle2D contained in both the specified Rectangle2D and in this Rectangle2D.

Since:

1.2

intersect

public static void intersect(Rectangle2D src1,
                             Rectangle2D src2,
                             Rectangle2D dest)

Intersects the pair of specified source Rectangle2D objects and puts the result into the specified destination Rectangle2D object. One of the source rectangles can also be the destination to avoid creating a third Rectangle2D object, but in this case the original points of this source rectangle will be overwritten by this method.

Parameters:

src1 - the first of a pair of Rectangle2D objects to be intersected with each other

src2 - the second of a pair of Rectangle2D objects to be intersected with each other

dest - the Rectangle2D that holds the results of the intersection of src1 and src2

Since:

1.2

createUnion

public abstract Rectangle2D createUnion(Rectangle2D r)

Returns a new Rectangle2D object representing the union of this Rectangle2D with the specified Rectangle2D.

Parameters:

r - the Rectangle2D to be combined with this Rectangle2D

Returns:

the smallest Rectangle2D containing both the specified Rectangle2D and this Rectangle2D.

Since:

1.2

union

public static void union(Rectangle2D src1,
                         Rectangle2D src2,
                         Rectangle2D dest)

Unions the pair of source Rectangle2D objects and puts the result into the specified destination Rectangle2D object. One of the source rectangles can also be the destination to avoid creating a third Rectangle2D object, but in this case the original points of this source rectangle will be overwritten by this method.

Parameters:

src1 - the first of a pair of Rectangle2D objects to be combined with each other

src2 - the second of a pair of Rectangle2D objects to be combined with each other

dest - the Rectangle2D that holds the results of the union of src1 and src2

Since:

1.2

add

public void add(double newx,
                double newy)

Adds a point, specified by the double precision arguments newx and newy, to this Rectangle2D. The resulting Rectangle2D is the smallest Rectangle2D that contains both the original Rectangle2D and the specified point.

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 left or bottom edge of the enlarged rectangle, contains returns false for that point.

Parameters:

newx - the X coordinate of the new point

newy - the Y coordinate of the new point

Since:

1.2

add

public void add(Point2D pt)

Adds the Point2D object pt to this Rectangle2D. The resulting Rectangle2D is the smallest Rectangle2D that contains both the original Rectangle2D and the specified Point2D.

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 left or bottom edge of the enlarged rectangle, contains returns false for that point.

Parameters:

pt - the new Point2D to add to this Rectangle2D.

Since:

1.2

add

public void add(Rectangle2D r)

Adds a Rectangle2D object to this Rectangle2D. The resulting Rectangle2D is the union of the two Rectangle2D objects.

Parameters:

r - the Rectangle2D to add to this Rectangle2D.

Since:

1.2

getPathIterator

public PathIterator getPathIterator(AffineTransform at)

Returns an iteration object that defines the boundary of this Rectangle2D. The iterator for this class is multi-threaded safe, which means that this Rectangle2D class guarantees that modifications to the geometry of this Rectangle2D object do not affect any iterations of that geometry that are already in process.

Parameters:

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 Rectangle2D, one segment at a time.

Since:

1.2

getPathIterator

public PathIterator getPathIterator(AffineTransform at,
                                    double flatness)

Returns an iteration object that defines the boundary of the flattened Rectangle2D. Since rectangles are already flat, the flatness parameter is ignored. The iterator for this class is multi-threaded safe, which means that this Rectangle2D class guarantees that modifications to the geometry of this Rectangle2D object do not affect any iterations of that geometry that are already in process.

Specified by:

getPathIterator in interface Shape

Overrides:

getPathIterator in class RectangularShape

Parameters:

at - an optional AffineTransform to be applied to the coordinates as they are returned in the iteration, or null if untransformed coordinates are desired

flatness - the maximum distance that the line segments used to approximate the curved segments are allowed to deviate from any point on the original curve. Since rectangles are already flat, the flatness parameter is ignored.

Returns:

the PathIterator object that returns the geometry of the outline of this Rectangle2D, one segment at a time.

Since:

1.2

hashCode

public int hashCode()

Returns the hashcode for this Rectangle2D.

Overrides:

hashCode in class Object

Returns:

the hashcode for this Rectangle2D.

Since:

1.2

See Also:

Object.equals(java.lang.Object), System.identityHashCode(java.lang.Object)

equals

public boolean equals(Object obj)

Determines whether or not the specified Object is equal to this Rectangle2D. The specified Object is equal to this Rectangle2D if it is an instance of Rectangle2D and if its location and size are the same as this Rectangle2D.

Overrides:

equals in class Object

Parameters:

obj - an Object to be compared with this Rectangle2D.

Returns:

true if obj is an instance of Rectangle2D and has the same values; false otherwise.

Since:

1.2

See Also:

Object.hashCode(), HashMap