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java.awt
public class: Rectangle [javadoc | source]
java.lang.Object
   java.awt.geom.RectangularShape
      java.awt.geom.Rectangle2D
         java.awt.Rectangle

All Implemented Interfaces:
    Shape, java$io$Serializable, Cloneable

Direct Known Subclasses:
    ComposedTextCaret, DefaultCaret, AWTCaret, BasicCaret

A Rectangle specifies an area in a coordinate space that is enclosed by the Rectangle object's upper-left point {@code (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 {@code 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 {@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 #add(Point) method were being called.

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.

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.

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:

    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.

Field Summary
public  int x    The X coordinate of the upper-left corner of the Rectangle. 
public  int y    The Y coordinate of the upper-left corner of the Rectangle. 
public  int width    The width of the Rectangle. 
public  int height    The height of the Rectangle. 
Fields inherited from java.awt.geom.Rectangle2D:
OUT_LEFT,  OUT_TOP,  OUT_RIGHT,  OUT_BOTTOM
Constructor:
 public Rectangle() 
 public Rectangle(Rectangle r) 
    Constructs a new Rectangle, initialized to match the values of the specified Rectangle.
    Parameters:
    r - the Rectangle from which to copy initial values to a newly constructed Rectangle
    since: 1.1 -
 public Rectangle(Point p) 
    Constructs a new Rectangle whose upper-left corner is the specified Point, and whose width and height are both zero.
    Parameters:
    p - a Point that is the top left corner of the Rectangle
 public Rectangle(Dimension d) 
    Constructs a new Rectangle whose top left corner is (0, 0) and whose width and height are specified by the Dimension argument.
    Parameters:
    d - a Dimension, specifying width and height
 public Rectangle(int width,
    int height) 
 public Rectangle(Point p,
    Dimension d) 
    Constructs a new Rectangle whose upper-left corner is specified by the Point argument, and whose width and height are specified by the Dimension argument.
    Parameters:
    p - a Point that is the upper-left corner of the Rectangle
    d - a Dimension, representing the width and height of the Rectangle
 public Rectangle(int x,
    int y,
    int width,
    int height) 
Method from java.awt.Rectangle Summary:
add,   add,   add,   contains,   contains,   contains,   contains,   createIntersection,   createUnion,   equals,   getBounds,   getBounds2D,   getHeight,   getLocation,   getSize,   getWidth,   getX,   getY,   grow,   inside,   intersection,   intersects,   isEmpty,   move,   outcode,   reshape,   resize,   setBounds,   setBounds,   setLocation,   setLocation,   setRect,   setSize,   setSize,   toString,   translate,   union
Methods from java.awt.geom.Rectangle2D:
add,   add,   add,   contains,   contains,   createIntersection,   createUnion,   equals,   getBounds2D,   getPathIterator,   getPathIterator,   hashCode,   intersect,   intersects,   intersectsLine,   intersectsLine,   outcode,   outcode,   setFrame,   setRect,   setRect,   union
Methods from java.awt.geom.RectangularShape:
clone,   contains,   contains,   getBounds,   getCenterX,   getCenterY,   getFrame,   getHeight,   getMaxX,   getMaxY,   getMinX,   getMinY,   getPathIterator,   getWidth,   getX,   getY,   intersects,   isEmpty,   setFrame,   setFrame,   setFrame,   setFrameFromCenter,   setFrameFromCenter,   setFrameFromDiagonal,   setFrameFromDiagonal
Methods from java.lang.Object:
clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
Method from java.awt.Rectangle Detail:
 public  void add(Point pt) 
    Adds the specified {@code Point} to the bounds of this {@code Rectangle}.

    If this {@code Rectangle} has any dimension less than zero, the rules for non-existant rectangles apply. In that case, the new bounds of this {@code Rectangle} will have a location equal to the coordinates of the specified {@code Point} 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 {@code Rectangle}, a 1x1 rectangle should be added instead:

        r.add(pt.x, pt.y, 1, 1);
    
 public  void add(Rectangle r) 
    Adds a Rectangle to this Rectangle. The resulting Rectangle is the union of the two rectangles.

    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.

    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 #add(Point) method, but contribute no further dimension beyond that.

    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.

 public  void add(int newx,
    int newy) 
    Adds a point, specified by the integer arguments {@code newx,newy} to the bounds of this {@code Rectangle}.

    If this {@code Rectangle} has any dimension less than zero, the rules for non-existant 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.

    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 {@code Rectangle}, a 1x1 rectangle should be added instead:

        r.add(newx, newy, 1, 1);
    
 public boolean contains(Point p) 
    Checks whether or not this Rectangle contains the specified Point.
 public boolean contains(Rectangle r) 
    Checks whether or not this Rectangle entirely contains the specified Rectangle.
 public boolean contains(int x,
    int y) 
    Checks whether or not this Rectangle contains the point at the specified location {@code (x,y)}.
 public boolean contains(int X,
    int Y,
    int W,
    int H) 
    Checks whether this Rectangle entirely contains the Rectangle at the specified location {@code (X,Y)} with the specified dimensions {@code (W,H)}.
 public Rectangle2D createIntersection(Rectangle2D r) 
    {@inheritDoc}
 public Rectangle2D createUnion(Rectangle2D r) 
    {@inheritDoc}
 public boolean equals(Object obj) 
    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.

 public Rectangle getBounds() 
    Gets the bounding Rectangle of this Rectangle.

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

 public Rectangle2D getBounds2D() 
    {@inheritDoc}
 public double getHeight() 
    Returns the height of the bounding Rectangle in double precision.
 public Point getLocation() 
    Returns the location of this Rectangle.

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

 public Dimension getSize() 
    Gets the size of this Rectangle, represented by the returned Dimension.

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

 public double getWidth() 
    Returns the width of the bounding Rectangle in double precision.
 public double getX() 
    Returns the X coordinate of the bounding Rectangle in double precision.
 public double getY() 
    Returns the Y coordinate of the bounding Rectangle in double precision.
 public  void grow(int h,
    int v) 
    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 {@code (x - h, y - v)} as its upper-left corner, width of {@code (width + 2h)}, and a height of {@code (height + 2v)}.

    If negative values are supplied for h and v, the size of the Rectangle 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.

 public boolean inside(int X,
    int Y) 
Deprecated! As - of JDK version 1.1, replaced by contains(int, int).

    Checks whether or not this Rectangle contains the point at the specified location {@code (X,Y)}.
 public Rectangle intersection(Rectangle r) 
    Computes the intersection of this Rectangle with the specified Rectangle. Returns a new Rectangle that represents the intersection of the two rectangles. If the two rectangles do not intersect, the result will be an empty rectangle.
 public boolean intersects(Rectangle r) 
    Determines whether or not this Rectangle and the specified Rectangle intersect. Two rectangles intersect if their intersection is nonempty.
 public boolean isEmpty() 
    {@inheritDoc}
 public  void move(int x,
    int y) 
Deprecated! As - of JDK version 1.1, replaced by setLocation(int, int).

    Moves this Rectangle to the specified location.

 public int outcode(double x,
    double y) 
    {@inheritDoc}
 public  void reshape(int x,
    int y,
    int width,
    int height) 
Deprecated! As - of JDK version 1.1, replaced by setBounds(int, int, int, int).

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

 public  void resize(int width,
    int height) 
Deprecated! As - of JDK version 1.1, replaced by setSize(int, int).

    Sets the size of this Rectangle to the specified width and height.

 public  void setBounds(Rectangle r) 
    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.

 public  void setBounds(int x,
    int y,
    int width,
    int 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.

 public  void setLocation(Point p) 
    Moves this Rectangle to the specified location.

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

 public  void setLocation(int x,
    int y) 
    Moves this Rectangle to the specified location.

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

 public  void setRect(double x,
    double y,
    double width,
    double height) 
    Sets the bounds of this {@code Rectangle} to the integer bounds which encompass the specified {@code x}, {@code y}, {@code width}, and {@code height}. If the parameters specify a {@code Rectangle} that exceeds the maximum range of integers, the result will be the best representation of the specified {@code Rectangle} intersected with the maximum integer bounds.
 public  void setSize(Dimension d) 
    Sets the size of this Rectangle to match the specified Dimension.

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

 public  void setSize(int width,
    int height) 
    Sets the size of this Rectangle to the specified width and height.

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

 public String toString() 
    Returns a String representing this Rectangle and its values.
 public  void translate(int dx,
    int dy) 
    Translates this Rectangle the indicated distance, to the right along the X coordinate axis, and downward along the Y coordinate axis.
 public Rectangle union(Rectangle r) 
    Computes the union of this Rectangle with the specified Rectangle. Returns a new Rectangle that represents the union of the two rectangles.

    If either {@code Rectangle} has any dimension less than zero the rules for non-existant rectangles apply. If only one has a dimension less than zero, then the result will be a copy of the other {@code Rectangle}. If both have dimension less than zero, then the result will have at least one dimension less than zero.

    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.