Rectangle.java   [plain text]


/* Copyright (C) 1999, 2000, 2001, 2002  Free Software Foundation

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package java.awt;

import java.awt.geom.*;
import java.io.Serializable;

/* Status:  Mostly complete. Some of the Java2D stuff is commented out. */

/**
 * This class represents a rectangle and all the interesting things you
 * might want to do with it.  Note that the coordinate system uses
 * the origin (0,0) as the top left of the screen, with the x and y
 * values increasing as they move to the right and down respectively.
 *
 * @author Warren Levy  <warrenl@cygnus.com>
 * @author Aaron M. Renn (arenn@urbanophile.com)
 */
public class Rectangle extends Rectangle2D
  implements Cloneable, Shape, Serializable
{
  /**
  * The X coordinate of the top-left corner of the rectangle.
  */
  public int x;

  /**
  * The Y coordinate of the top-left corner of the rectangle;
  */
  public int y;

  /**
  * The width of the rectangle
  */
  public int width;

  /**
  * The height of the rectangle
  */
  public int height;

  /**
   * Initializes a new instance of <code>Rectangle</code> with a top
   * left corner at (0,0) and a width and height of 0.
   */
  public Rectangle()
  {
    x = 0;
    y = 0;
    width = 0;
    height = 0;
  }

  /**
   * Initializes a new instance of <code>Rectangle</code> from the
   * coordinates of the specified rectangle.
   *
   * @param rect The rectangle to copy from.
   */
  public Rectangle(Rectangle r)
  {
    x = r.x;
    y = r.y;
    width = r.width;
    height = r.height;
  }

  /**
   * Initializes a new instance of <code>Rectangle</code> from the specified
   * inputs.
   *
   * @param x The X coordinate of the top left corner of the rectangle.
   * @param y The Y coordinate of the top left corner of the rectangle.
   * @param width The width of the rectangle.
   * @param height The height of the rectangle.
   */
  public Rectangle(int x, int y, int width, int height)
  {
    this.x = x;
    this.y = y;
    this.width = width;
    this.height = height;
  }

  /**
   * Initializes a new instance of <code>Rectangle</code> with the specified
   * width and height.  The upper left corner of the rectangle will be at
   * the origin (0,0).
   *
   * @param width The width of the rectangle.
   * @param height the height of the rectange.
   */
  public Rectangle(int width, int height)
  {
    x = 0;
    y = 0;
    this.width = width;
    this.height = height;
  }

  /**
   * Initializes a new instance of <code>Rectangle</code> with a top-left
   * corner represented by the specified point and the width and height
   * represented by the specified dimension.
   *
   * @param point The upper left corner of the rectangle.
   * @param dim The width and height of the rectangle.
   */
  public Rectangle(Point p, Dimension d)
  {
    x = p.x;
    y = p.y;
    width = d.width;
    height = d.height;
  }

  /**
   * Initializes a new instance of <code>Rectangle</code> with a top left
   * corner at the specified point and a width and height of zero.
   *
   * @param poin The upper left corner of the rectangle.
   */
  public Rectangle(Point p)
  {
    x = p.x;
    y = p.y;
    width = 0;
    height = 0;
  }

  /**
   * Initializes a new instance of <code>Rectangle</code> with an
   * upper left corner at the origin (0,0) and a width and height represented
   * by the specified dimension.
   *
   * @param dim The width and height of the rectangle.
   */
  public Rectangle(Dimension d)
  {
    x = 0;
    y = 0;
    width = d.width;
    height = d.height;
  }

  /**
   * Returns the bounding rectangle for this rectangle, which is simply
   * this rectange itself.
   *
   * @return This rectangle.
   */
  public Rectangle getBounds ()
  {
    return (Rectangle) this.clone();
  }

  /**
   * Modifies this rectangle so that it represents the smallest rectangle 
   * that contains both the existing rectangle and the specified point.
   *
   * @param x The X coordinate of the point to add to this rectangle.
   * @param y The Y coordinate of the point to add to this rectangle.
   */
  public void add(int newx, int newy)
  {
    int x = this.x > newx ? newx : this.x;
    int y = this.y > newy ? newy : this.y;
    width = (this.x + width > newx ? this.x + width : newx) - x;
    height = (this.y + height > newy ? this.y + height : newy) - y;
    this.x = x;
    this.y = y;
  }

  /**
   * Modifies this rectangle so that it represents the smallest rectangle 
   * that contains both the existing rectangle and the specified point.
   *
   * @param point The point to add to this rectangle.
   */
  public void add(Point pt)
  {
    add (pt.x, pt.y);
  }

  /**
   * Modifies this rectangle so that it represents the smallest rectangle 
   * that contains both the existing rectangle and the specified rectangle.
   *
   * @param rect The rectangle to add to this rectangle.
   */
  public void add(Rectangle r)
  {
    int x = this.x > r.x ? r.x : this.x;
    int y = this.y > r.y ? r.y : this.y;
    width = (this.x + width > r.x + r.width ? 
             this.x + width : r.x + r.width) - x;
    height = (this.y + height > r.y + r.height ?
              this.y + height : r.y + r.height) - y;
    this.x = x;
    this.y = y;
  }

  /**
   * Tests whether or not the specified point is inside this rectangle.
   *
   * @param x The X coordinate of the point to test.
   * @param y The Y coordinate of the point to test.
   *
   * @return <code>true</code> if the point is inside the rectangle,
   * <code>false</code> otherwise.
   */
  public boolean contains(int x, int y)
  {
    return (x >= this.x && x <= this.x + this.width
            && y >= this.y && y <= this.y + this.height);
  }   

  public boolean contains(int x, int y, int w, int h)
  {
    return (x >= this.x && x + w <= this.x + this.width
            && y >= this.y && y + h <= this.y + this.height);
  }

  /**
   * Tests whether or not the specified point is inside this rectangle.
   *
   * @param point The point to test.
   *
   * @return <code>true</code> if the point is inside the rectangle,
   * <code>false</code> otherwise.
   */
  public boolean contains(Point p)
  {
    return contains(p.x, p.y);
  }

  public boolean contains(Rectangle r)
  {
    return contains(r.x, r.y, r.width, r.height);
  }

  /**
   * Tests this rectangle for equality against the specified object.  This
   * will be true if an only if the specified object:
   * <p>
   * <ul>
   * <li>Is not <code>null</code>.
   * <li>Is an instance of <code>Rectangle</code>.
   * <li>Has X and Y coordinates identical to this rectangle.
   * <li>Has a width and height identical to this rectangle.
   * </ul>
   *
   * @param obj The object to test against for equality.
   *
   * @return <code>true</code> if the specified object is equal to this one,
   * <code>false</code> otherwise.
   */
  public boolean equals(Object obj)
  {
    if (obj instanceof Rectangle)
      {
	Rectangle r = (Rectangle) obj;
	return (r.x == x 
	        && r.y == y 
		&& r.width == width 
		&& r.height == height);
      }
    return false;
  }

  public double getHeight()
  {
    return (double) this.height;     
  }

  /**
   * Returns the location of this rectangle, which is the coordinates of
   * its upper left corner.
   *
   * @return The point where this rectangle is located.
   */
  public Point getLocation()
  {
    return new Point(x,y);
  }

  /**
   * Returns the size of this rectangle.
   *
   * @return The size of this rectangle.
   */
  public Dimension getSize()
  {
    return new Dimension(width, height);
  }

  public double getWidth()
  {
    return (double) this.width;
  }

  public double getX()
  {
    return (double) x;
  }

  public double getY()
  {
    return (double) y;
  }

  /**
   * Expands the rectangle by the specified amount.  The horizontal
   * and vertical expansion values are applied both to the X,Y coordinate
   * of this rectangle, and its width and height.  Thus the width and
   * height will increase by 2h and 2v accordingly.
   *
   * @param h The horizontal expansion value.
   * @param v The vertical expansion value.
   */
  public void grow(int h, int v)
  {
    width += h;
    height += v;
  }

  /**
   * Tests whether or not the specified point is inside this rectangle.
   *
   * @param x The X coordinate of the point to test.
   * @param y The Y coordinate of the point to test.
   *
   * @return <code>true</code> if the point is inside the rectangle,
   * <code>false</code> otherwise.
   *
   * @deprecated This method is deprecated in favor of
   * <code>contains(int, int)</code>.
   */
  public boolean inside(int x, int y)
  {
    return contains(x, y);
  }

  /**
   * Determines the rectange which is formed by the intersection of this
   * rectangle with the specified rectangle.
   *
   * @param rect The rectange to calculate the intersection with.
   *
   * @return The rectangle bounding the intersection.
   *
   * @specnote If there is no intersection, an empty rectangle at 0,0 
   *           is returned.
   */
  public Rectangle intersection(Rectangle r)
  {
    int newx = x < r.x ? r.x : x;
    int newy = y < r.y ? r.y : y;
    int neww = (x + width < r.x + r.width ?
        	x + width : r.x + r.width) - newx;
    int newh = (y + height < r.y + r.height ?
        	y + height : r.y + r.height) - newy;
    if (neww >= 0 && newh >= 0)
      return new Rectangle(newx, newy, neww, newh);
    else
      return new Rectangle(0, 0, 0, 0);
  }

  /**
   * Tests whether or not the specified rectangle intersects this rectangle.
   *
   * @param rect The rectangle to test against.
   *
   * @return <code>true</code> if the specified rectangle intersects this
   * one, <code>false</code> otherwise.
   *
   * @specnote If the intersection is at an edge or corner only (an empty
   *           intersection with a non-zero location), false is returned.
   */
  public boolean intersects(Rectangle r)
  {
    int neww = (x + width < r.x + r.width ?
        	x + width : r.x + r.width) - (x < r.x ? r.x : x);
    int newh = (y + height < r.y + r.height ?
        	y + height : r.y + r.height) - (y < r.y ? r.y : y);
    return (neww > 0 && newh > 0);
  }

  /**
   * Tests whether or not this rectangle is empty.  An empty rectangle
   * has a width or height of zero.
   *
   * @return <code>true</code> if the rectangle is empty, <code>false</code>
   * otherwise.
   */
  public boolean isEmpty()
  {
    return !(width > 0 && height > 0);
  }

  /**
   * Moves the location of this rectangle by setting its upper left
   * corner to the specified coordinates.
   * // FIXME: Is this true?
   *
   * @param x The new X coordinate for this rectangle.
   * @param y The new Y coordinate for this rectangle.
   *
   * @deprecated This method is deprecated in favor of
   * <code>setLocation(int, int)</code>.
   */
  public void move(int x, int y)
  {
    setLocation(x, y);
  }

  public int outcode(double x, double y)
  {
    // FIXME
    return 0;
  }

  /**
   * Updates this rectangle to have the specified dimensions.
   *
   * @param x The new X coordinate of the upper left hand corner.
   * @param y The new Y coordinate of the upper left hand corner.
   * @param width The new width of this rectangle.
   * @param height The new height of this rectangle.
   *
   * @deprecated This method is deprecated in favor of 
   * <code>setBounds(int, int, int, int)</code>.
   */
  public void reshape(int x, int y, int width, int height)
  {
    setBounds(x, y, width, height);
  }

  /**
   * Sets the size of this rectangle based on the specified dimensions.
   *
   * @param width The new width of the rectangle.
   * @param height The new height of the rectangle.
   *
   * @deprecated This method is deprecated in favor of
   * <code>setSize(int, int)</code>.
   */
  public void resize(int width, int height)
  {
    setSize(width, height);
  }

  /**
   * Updates this rectangle to have the specified dimensions.
   *
   * @param x The new X coordinate of the upper left hand corner.
   * @param y The new Y coordinate of the upper left hand corner.
   * @param width The new width of this rectangle.
   * @param height The new height of this rectangle.
   */
  public void setBounds(int x, int y, int width, int height)
  {
    this.x = x;
    this.y = y;
    this.width = width;
    this.height = height;
  }

  /**
   * Updates this rectangle to match the dimensions of the specified 
   * rectangle.
   *
   * @param rect The rectangle to update from.
   */
  public void setBounds(Rectangle r)
  {
    this.x = r.x;
    this.y = r.y;
    this.width = r.width;
    this.height = r.height;     
  }

  /**
   * Moves the location of this rectangle by setting its upper left
   * corner to the specified coordinates.
   * // FIXME: Is this true?
   *
   * @param x The new X coordinate for this rectangle.
   * @param y The new Y coordinate for this rectangle.
   */
  public void setLocation(int x, int y)
  {
    this.x = x;
    this.y = y;
  }

  /**
   * Moves the location of this rectangle by setting its upper left
   * corner to the specified point.
   * // FIXME: Is this true?
   *
   * @param point The point to move the rectange to.
   */
  public void setLocation(Point p)
  {
    this.x = p.x;
    this.y = p.y;
  }

  public void setRect(double x, double y, double width, double height)
  {
    this.x = (int) x;
    this.y = (int) y;
    this.width = (int) width;
    this.height = (int) height;
  }

  /**
   * Sets the size of this rectangle based on the specified dimensions.
   *
   * @param dim The new dimensions of the rectangle.
   */
  public void setSize(Dimension d)
  {
    this.width = d.width;
    this.height = d.height;
  }

  /**
   * Sets the size of this rectangle based on the specified dimensions.
   *
   * @param width The new width of the rectangle.
   * @param height The new height of the rectangle.
   */
  public void setSize(int width, int height)
  {
    this.width = width;
    this.height = height;
  }

  public void translate(int x, int y)
  {
    x += x;
    y += y;
  }

  /**
   * Returns the smallest rectangle that contains both this rectangle
   * and the specified rectangle.
   *
   * @param rect The rectangle to compute the union with.
   *
   * @return The smallest rectangle containing both rectangles.
   */
  public Rectangle union(Rectangle r)
  {
    int newx = x > r.x ? r.x : x;
    int newy = y > r.y ? r.y : y;     
    int neww = (this.x + width > r.x + r.width ? 
               this.x + width : r.x + r.width) - newx;
    int newh = (this.y + height > r.y + r.height ?
        	this.y + height : r.y + r.height) - newy;
    return new Rectangle(newx, newy, neww, newh);
  }

  // Commented out until we have Rectangle2D
  public Rectangle2D createIntersection(Rectangle2D r)
  {
    // FIXME: maybe we should consider returning a Rectangle or
    // Rectangle2D.Float depending on type of R.
    Rectangle2D.Double res = new Rectangle2D.Double ();
    intersect (this, r, res);
    return res;
  }

  public Rectangle2D createUnion(Rectangle2D r)
  {
    // FIXME: maybe we should consider returning a Rectangle or
    // Rectangle2D.Float depending on type of R.
    Rectangle2D.Double res = new Rectangle2D.Double ();
    union (this, r, res);
    return res;
  }

  public Rectangle2D getBounds2D()
  {
    return new Rectangle (x, y, width, height);
  }

  /**
   * Returns a string representation of this rectangle.
   *
   * @return A string representation of this rectangle.
   */
  public String toString()
  {
    return getClass().getName() + "[x=" + x + ",y=" + y + ",width=" + width + 
           ",height=" + height + "]";
  }

  /**
   * Returns a hash value for this object.
   *
   * @return A hash value for this object.
   */
  public int hashCode()
  {
    return x * y * width * height * 37;
  }
}