rectangle.java

来自「纯java操作系统jnode,安装简单和操作简单的个人使用的Java操作系统」· Java 代码 · 共 701 行 · 第 1/2 页

/* Rectangle.java -- represents a graphics rectangle
   Copyright (C) 1999, 2000, 2001, 2002 Free Software Foundation

This file is part of GNU Classpath.

GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

GNU Classpath 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 for more details.

You should have received a copy of the GNU General Public License
along with GNU Classpath; see the file COPYING.  If not, write to the
Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA.

Linking this library statically or dynamically with other modules is
making a combined work based on this library.  Thus, the terms and
conditions of the GNU General Public License cover the whole
combination.

As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
modules, and to copy and distribute the resulting executable under
terms of your choice, provided that you also meet, for each linked
independent module, the terms and conditions of the license of that
module.  An independent module is a module which is not derived from
or based on this library.  If you modify this library, you may extend
this exception to your version of the library, but you are not
obligated to do so.  If you do not wish to do so, delete this
exception statement from your version. */

package java.awt;

import java.awt.geom.Rectangle2D;
import java.io.Serializable;

/**
 * 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.
 *
 * <p>It is valid for a rectangle to have negative width or height; but it
 * is considered to have no area or internal points. Therefore, the behavior
 * in methods like <code>contains</code> or <code>intersects</code> is
 * undefined unless the rectangle has positive width and height.
 *
 * <p>There are some public fields; if you mess with them in an inconsistent
 * manner, it is your own fault when you get NullPointerException,
 * ArrayIndexOutOfBoundsException, or invalid results. Also, this class is
 * not threadsafe.
 *
 * @author Warren Levy  <[e-mail]>
 * @author Aaron M. Renn <[e-mail]>
 * @author Eric Blake <[e-mail]>
 * @since 1.0
 * @status updated to 1.4
 */
public class Rectangle extends Rectangle2D implements Shape, Serializable {
	/**
	 * Compatible with JDK 1.0+.
	 */
	private static final long serialVersionUID = -4345857070255674764L;

	/**
	 * The X coordinate of the top-left corner of the rectangle.
	 *
	 * @see #setLocation(int, int)
	 * @see #getLocation()
	 * @serial the x coordinate
	 */
	public int x;

	/**
	 * The Y coordinate of the top-left corner of the rectangle.
	 *
	 * @see #setLocation(int, int)
	 * @see #getLocation()
	 * @serial the y coordinate
	 */
	public int y;

	/**
	 * The width of the rectangle.
	 *
	 * @see #setSize(int, int)
	 * @see #getSize()
	 * @serial
	 */
	public int width;

	/**
	 * The height of the rectangle.
	 *
	 * @see #setSize(int, int)
	 * @see #getSize()
	 * @serial
	 */
	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() {
	}

	/**
	 * Initializes a new instance of <code>Rectangle</code> from the
	 * coordinates of the specified rectangle.
	 *
	 * @param r the rectangle to copy from
	 * @throws NullPointerException if r is null
	 * @since 1.1
	 */
	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
	 * @param y the Y coordinate of the top left corner
	 * @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) {
		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 p the upper left corner of the rectangle
	 * @param d the width and height of the rectangle
	 * @throws NullPointerException if p or d is null
	 */
	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 p the upper left corner of the rectangle
	 */
	public Rectangle(Point p) {
		x = p.x;
		y = p.y;
	}

	/**
	 * 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 d the width and height of the rectangle
	 */
	public Rectangle(Dimension d) {
		width = d.width;
		height = d.height;
	}

	/**
	 * Get the X coordinate of the upper-left corner.
	 *
	 * @return the value of x, as a double
	 */
	public double getX() {
		return x;
	}

	/**
	 * Get the Y coordinate of the upper-left corner.
	 *
	 * @return the value of y, as a double
	 */
	public double getY() {
		return y;
	}

	/**
	 * Get the width of the rectangle.
	 *
	 * @return the value of width, as a double
	 */
	public double getWidth() {
		return width;
	}

	/**
	 * Get the height of the rectangle.
	 *
	 * @return the value of height, as a double
	 */
	public double getHeight() {
		return height;
	}

	/**
	 * Returns the bounds of this rectangle. A pretty useless method, as this
	 * is already a rectangle; it is included to mimic the
	 * <code>getBounds</code> method in Component.
	 *
	 * @return a copy of this rectangle
	 * @see #setBounds(Rectangle)
	 * @since 1.1
	 */
	public Rectangle getBounds() {
		return new Rectangle(this);
	}

	/**
	 * Returns the high-precision bounds of this rectangle. A pretty useless
	 * method, as this is already a rectangle.
	 *
	 * @return a copy of this rectangle
	 * @see #setBounds(Rectangle)
	 * @since 1.2
	 */
	public Rectangle2D getBounds2D() {
		return new Rectangle(x, y, width, height);
	}

	/**
	 * Updates this rectangle to match the dimensions of the specified
	 * rectangle.
	 *
	 * @param r the rectangle to update from
	 * @throws NullPointerException if r is null
	 * @see #setBounds(int, int, int, int)
	 * @since 1.1
	 */
	public void setBounds(Rectangle r) {
		x = r.x;
		y = r.y;
		width = r.width;
		height = r.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
	 * @since 1.1
	 */
	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 have the specified dimensions, as rounded to
	 * integers.
	 *
	 * @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
	 * @since 1.2
	 */
	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;
	}

	/**
	 * 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 use {@link #setBounds(int, int, int, int)} instead
	 */
	public void reshape(int x, int y, int width, int height) {
		setBounds(x, y, width, height);
	}

	/**
	 * Returns the location of this rectangle, which is the coordinates of
	 * its upper left corner.
	 *
	 * @return the point where this rectangle is located
	 * @see #setLocation(Point)
	 * @since 1.1
	 */
	public Point getLocation() {
		return new Point(x, y);
	}

	/**
	 * Moves the location of this rectangle by setting its upper left
	 * corner to the specified point.
	 *
	 * @param p the point to move the rectangle to
	 * @throws NullPointerException if p is null
	 * @see #getLocation()
	 * @since 1.1
	 */
	public void setLocation(Point p) {
		this.x = p.x;
		this.y = p.y;
	}

	/**
	 * Moves the location of this rectangle by setting its upper left
	 * corner to the specified coordinates.
	 *
	 * @param x the new X coordinate for this rectangle
	 * @param y the new Y coordinate for this rectangle