org.eclipse.swt.graphics
Class Rectangle

java.lang.Object
  org.eclipse.swt.graphics.Rectangle

public final class Rectangle
extends java.lang.Object

Instances of this class represent rectangular areas in an (x, y) coordinate system. The top left corner of the rectangle is specified by its x and y values, and the extent of the rectangle is specified by its width and height.

The coordinate space for rectangles and points is considered to have increasing values downward and to the right from its origin making this the normal, computer graphics oriented notion of (x, y) coordinates rather than the strict mathematical one.

The hashCode() method in this class uses the values of the public fields to compute the hash value. When storing instances of the class in hashed collections, do not modify these fields after the object has been inserted.

Application code does not need to explicitly release the resources managed by each instance when those instances are no longer required, and thus no dispose() method is provided.

Since:

1.0

See Also:

Point

Field Summary

int	height the height of the rectangle
int	width the width of the rectangle
int	x the x coordinate of the rectangle
int	y the y coordinate of the rectangle

Constructor Summary

Rectangle(int x, int y, int width, int height)
Construct a new instance of this class given the x, y, width and height values.

Method Summary

void	add(Rectangle rect) Destructively replaces the x, y, width and height values in the receiver with ones which represent the union of the rectangles specified by the receiver and the given rectangle.
boolean	contains(int x, int y) Returns true if the point specified by the arguments is inside the area specified by the receiver, and false otherwise.
boolean	contains(Point pt) Returns true if the given point is inside the area specified by the receiver, and false otherwise.
boolean	equals(java.lang.Object object) Compares the argument to the receiver, and returns true if they represent the same object using a class specific comparison.
int	hashCode() Returns an integer hash code for the receiver.
void	intersect(Rectangle rect) Destructively replaces the x, y, width and height values in the receiver with ones which represent the intersection of the rectangles specified by the receiver and the given rectangle.
Rectangle	intersection(Rectangle rect) Returns a new rectangle which represents the intersection of the receiver and the given rectangle.
boolean	intersects(int x, int y, int width, int height) Returns true if the rectangle described by the arguments intersects with the receiver and false otherwise.
boolean	intersects(Rectangle rect) Returns true if the given rectangle intersects with the receiver and false otherwise.
boolean	isEmpty() Returns true if the receiver does not cover any area in the (x, y) coordinate plane, and false if the receiver does cover some area in the plane.
java.lang.String	toString() Returns a string containing a concise, human-readable description of the receiver.
Rectangle	union(Rectangle rect) Returns a new rectangle which represents the union of the receiver and the given rectangle.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

x

public int x

the x coordinate of the rectangle

y

public int y

the y coordinate of the rectangle

width

public int width

the width of the rectangle

height

public int height

the height of the rectangle

Constructor Detail

Rectangle

public Rectangle(int x,
                 int y,
                 int width,
                 int height)

Construct a new instance of this class given the x, y, width and height values.

Parameters:

x - the x coordinate of the origin of the rectangle

y - the y coordinate of the origin of the rectangle

width - the width of the rectangle

height - the height of the rectangle

Method Detail

add

public void add(Rectangle rect)

Destructively replaces the x, y, width and height values in the receiver with ones which represent the union of the rectangles specified by the receiver and the given rectangle.

The union of two rectangles is the smallest single rectangle that completely covers both of the areas covered by the two given rectangles.

Parameters:

rect - the rectangle to merge with the receiver

Throws:

java.lang.IllegalArgumentException -

• ERROR_NULL_ARGUMENT - if the argument is null

contains

public boolean contains(int x,
                        int y)

Returns true if the point specified by the arguments is inside the area specified by the receiver, and false otherwise.

Parameters:

x - the x coordinate of the point to test for containment

y - the y coordinate of the point to test for containment

Returns:

true if the rectangle contains the point and false otherwise

contains

public boolean contains(Point pt)

Returns true if the given point is inside the area specified by the receiver, and false otherwise.

Parameters:

pt - the point to test for containment

Returns:

true if the rectangle contains the point and false otherwise

Throws:

java.lang.IllegalArgumentException -

• ERROR_NULL_ARGUMENT - if the argument is null

equals

public boolean equals(java.lang.Object object)

Compares the argument to the receiver, and returns true if they represent the same object using a class specific comparison.

Overrides:

equals in class java.lang.Object

Parameters:

object - the object to compare with this object

Returns:

true if the object is the same as this object and false otherwise

See Also:

hashCode()

hashCode

public int hashCode()

Returns an integer hash code for the receiver. Any two objects that return true when passed to equals must return the same value for this method.

Overrides:

hashCode in class java.lang.Object

Returns:

the receiver's hash

See Also:

equals(Object)

intersect

public void intersect(Rectangle rect)

Destructively replaces the x, y, width and height values in the receiver with ones which represent the intersection of the rectangles specified by the receiver and the given rectangle.

Parameters:

rect - the rectangle to intersect with the receiver

Throws:

java.lang.IllegalArgumentException -

• ERROR_NULL_ARGUMENT - if the argument is null

since 3.0

intersection

public Rectangle intersection(Rectangle rect)

Returns a new rectangle which represents the intersection of the receiver and the given rectangle.

The intersection of two rectangles is the rectangle that covers the area which is contained within both rectangles.

Parameters:

rect - the rectangle to intersect with the receiver

Returns:

the intersection of the receiver and the argument

Throws:

java.lang.IllegalArgumentException -

• ERROR_NULL_ARGUMENT - if the argument is null

intersects

public boolean intersects(int x,
                          int y,
                          int width,
                          int height)

Returns true if the rectangle described by the arguments intersects with the receiver and false otherwise.

Two rectangles intersect if the area of the rectangle representing their intersection is not empty.

Parameters:

x - the x coordinate of the origin of the rectangle

y - the y coordinate of the origin of the rectangle

width - the width of the rectangle

height - the height of the rectangle

Returns:

true if the rectangle intersects with the receiver, and false otherwise

Throws:

java.lang.IllegalArgumentException -

• ERROR_NULL_ARGUMENT - if the argument is null

Since:

1.0

See Also:

intersection(Rectangle), isEmpty()

intersects

public boolean intersects(Rectangle rect)

Returns true if the given rectangle intersects with the receiver and false otherwise.

Two rectangles intersect if the area of the rectangle representing their intersection is not empty.

Parameters:

rect - the rectangle to test for intersection

Returns:

true if the rectangle intersects with the receiver, and false otherwise

Throws:

java.lang.IllegalArgumentException -

• ERROR_NULL_ARGUMENT - if the argument is null

See Also:

intersection(Rectangle), isEmpty()

isEmpty

public boolean isEmpty()

Returns true if the receiver does not cover any area in the (x, y) coordinate plane, and false if the receiver does cover some area in the plane.

A rectangle is considered to cover area in the (x, y) coordinate plane if both its width and height are non-zero.

Returns:

true if the receiver is empty, and false otherwise

toString

public java.lang.String toString()

Returns a string containing a concise, human-readable description of the receiver.

Overrides:

toString in class java.lang.Object

Returns:

a string representation of the rectangle

union

public Rectangle union(Rectangle rect)

Returns a new rectangle which represents the union of the receiver and the given rectangle.

The union of two rectangles is the smallest single rectangle that completely covers both of the areas covered by the two given rectangles.

Parameters:

rect - the rectangle to perform union with

Returns:

the union of the receiver and the argument

Throws:

java.lang.IllegalArgumentException -

• ERROR_NULL_ARGUMENT - if the argument is null

See Also:

add(Rectangle)