rectangle.java

《移动Agent技术》一书的所有章节源代码。

/*
 * @(#)Rectangle.java	1.27 97/07/08
 * 
 * Copyright (c) 1995, 1996 Sun Microsystems, Inc. All Rights Reserved.
 * 
 * This software is the confidential and proprietary information of Sun
 * Microsystems, Inc. ("Confidential Information").  You shall not
 * disclose such Confidential Information and shall use it only in
 * accordance with the terms of the license agreement you entered into
 * with Sun.
 * 
 * SUN MAKES NO REPRESENTATIONS OR WARRANTIES ABOUT THE SUITABILITY OF THE
 * SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
 * PURPOSE, OR NON-INFRINGEMENT. SUN SHALL NOT BE LIABLE FOR ANY DAMAGES
 * SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR DISTRIBUTING
 * THIS SOFTWARE OR ITS DERIVATIVES.
 * 
 * CopyrightVersion 1.1_beta
 * 
 */

package java.awt;

/**
 * A rectangle specifies an area in a coordinate space that is 
 * defined by the rectangle's top-left point (<i>x</i>,&nbsp;<i>y</i>) 
 * in the coordinate space, its width, and its height. 
 * <p>
 * A rectangle's <code>width</code> and <code>height</code> are 
 * public fields. The constructors that allow you to create a 
 * rectangle, and the methods that allow you to modify one, do not 
 * prevent you from setting a negative value for width or height. 
 * <p>
 * A rectangle whose width or height is negative is considered 
 * empty, and all methods defined by the <code>Rectangle</code> class  
 * behave accordingly. If the rectangle is empty, then the method 
 * <code>isEmpty</code> returns <code>true</code>. No point can be 
 * contained by or inside an empty rectangle, however the values of 
 * <code>width</code> and <code>height</code> are still valid. An 
 * empty rectangle still has a location in the coordinate space, and 
 * methods that change its size or location remain valid. The 
 * behavior of methods that operate on more than one rectangle is 
 * undefined if any of the participating rectangles has a negative 
 * <code>width</code> or <code>height</code>. These methods include 
 * <code>intersects</code>, <code>intersection</code>, and 
 * <code>union</code>. 
 *
 * @version 	1.27, 07/08/97
 * @author 	Sami Shaio
 * @since       JDK1.0
 */
public class Rectangle implements Shape, java.io.Serializable {

    /**
     * The <i>x</i> coordinate of the rectangle.
     * @since     JDK1.0
     */
    public int x;

    /**
     * The <i>y</i> coordinate of the rectangle.
     * @since     JDK1.0
     */
    public int y;

    /**
     * The width of the rectangle.
     * @since     JDK1.0.
     */
    public int width;

    /**
     * The height of the rectangle.
     * @since     JDK1.0
     */
    public int height;

    /*
     * JDK 1.1 serialVersionUID 
     */
     private static final long serialVersionUID = -4345857070255674764L;

    /**
     * Constructs a new rectangle whose top-left corner is at (0,&nbsp;0) 
     * in the coordinate space, and whose width and height are zero. 
     * @since     JDK1.0
     */
    public Rectangle() {
    	this(0, 0, 0, 0);
    }

    /**
     * Constructs a new rectangle, initialized to match the values of
     * the specificed rectangle.
     * @param r  a rectangle from which to copy initial values.
     * @since JDK1.1
     */
    public Rectangle(Rectangle r) {
    	this(r.x, r.y, r.width, r.height);
    }

    /**
     * Constructs a new rectangle whose top-left corner is specified as
     * (<code>x</code>,&nbsp;<code>y</code>) and whose width and height 
     * are specified by the arguments of the same name. 
     * @param     x   the <i>x</i> coordinate.
     * @param     y   the <i>y</i> coordinate.
     * @param     width    the width of the rectangle.
     * @param     height   the height of the rectangle.
     * @since     JDK1.0
     */
    public Rectangle(int x, int y, int width, int height) {
	this.x = x;
	this.y = y;
	this.width = width;
	this.height = height;
    }

    /**
     * Constructs a new rectangle whose top-left corner is at (0,&nbsp;0) 
     * in the coordinate space, and whose width and height are specified 
     * by the arguments of the same name. 
     * @param     width    the width of the rectangle.
     * @param     height   the height of the rectangle.
     * @since     JDK1.0
     */
    public Rectangle(int width, int height) {
	this(0, 0, width, height);
    }

    /**
     * Constructs a new rectangle whose top-left corner is specified 
     * by the <code>point</code> argument, and whose width and height  
     * are specified by the <code>dimension</code> argument. 
     * @param     p   a point, the top-left corner of the rectangle.
     * @param     d   a dimension, representing the width and height.
     * @since     JDK1.0 
     */
    public Rectangle(Point p, Dimension d) {
	this(p.x, p.y, d.width, d.height);
    }
    
    /**
     * Constructs a new rectangle whose top-left corner is the  
     * specified point, and whose width and height are zero. 
     * @param     p   the top left corner of the rectangle.
     * @since     JDK1.0
     */
    public Rectangle(Point p) {
	this(p.x, p.y, 0, 0);
    }
    
    /**
     * Constructs a new rectangle whose top left corner is  
     * (0,&nbsp;0) and whose width and height are specified  
     * by the <code>dimension</code> argument. 
     * @param     d   a dimension, specifying width and height.
     * @since     JDK1.0
     */
    public Rectangle(Dimension d) {
	this(0, 0, d.width, d.height);
    }

    /**
     * Gets the bounding rectangle of this rectangle.
     * <p>
     * This method is included for completeness, to parallel the
     * <code>getBounds</code> method of <code>Component</code>.
     * @return    a new rectangle, equal to the bounding rectangle 
     *                for this rectangle.
     * @see       java.awt.Component#getBounds
     * @since     JDK1.1
     */
    public Rectangle getBounds() {
	return new Rectangle(x, y, width, height);
    }	

    /**
     * Sets the bounding rectangle of this rectangle to match 
     * the specified rectangle.
     * <p>
     * This method is included for completeness, to parallel the
     * <code>setBounds</code> method of <code>Component</code>.
     * @param     r   a rectangle.
     * @see       java.awt.Component#setBounds(java.awt.Rectangle)
     * @since     JDK1.1
     */
    public void setBounds(Rectangle r) {
	setBounds(r.x, r.y, r.width, r.height);
    }	

    /**
     * Sets the bounding rectangle of this rectangle to the specified 
     * values for <code>x</code>, <code>y</code>, <code>width</code>, 
     * and <code>height</code>.
     * <p>
     * This method is included for completeness, to parallel the
     * <code>setBounds</code> method of <code>Component</code>.
     * @param     x       the new <i>x</i> coordinate for the top-left
     *                    corner of this rectangle.
     * @param     y       the new <i>y</i> coordinate for the top-left
     *                    corner of this rectangle.
     * @param     width   the new width for this rectangle.
     * @param     height  the new height for this rectangle.
     * @see       java.awt.Component#setBounds(int, int, int, int)
     * @since     JDK1.1
     */
    public void setBounds(int x, int y, int width, int height) {
    	reshape(x, y, width, height);
    }	

    /**
     * @deprecated As of JDK version 1.1,
     * replaced by <code>setBounds(int, int, int, int)</code>.
     */
    public void reshape(int x, int y, int width, int height) {
	this.x = x;
	this.y = y;
	this.width = width;
	this.height = height;
    }	

    /**
     * Returns the location of this rectangle.
     * <p>
     * This method is included for completeness, to parallel the
     * <code>getLocation</code> method of <code>Component</code>.
     * @see       java.awt.Component#getLocation
     * @since     JDK1.1
     */
    public Point getLocation() {
	return new Point(x, y);
    }	

    /**
     * Moves the rectangle to the specified location.
     * <p>
     * This method is included for completeness, to parallel the
     * <code>setLocation</code> method of <code>Component</code>.
     * @param     p  the new location for the point.
     * @see       java.awt.Component#setLocation(java.awt.Point)
     * @since     JDK1.1
     */
    public void setLocation(Point p) {
	setLocation(p.x, p.y);
    }	

    /**
     * Moves the rectangle to the specified location.
     * <p>
     * This method is included for completeness, to parallel the
     * <code>setLocation</code> method of <code>Component</code>.
     * @param     x  the <i>x</i> coordinate of the new location.
     * @param     y  the <i>y</i> coordinate of the new location.
     * @see       java.awt.Component#setLocation(int, int)
     * @since     JDK1.1
     */
    public void setLocation(int x, int y) {
	move(x, y);
    }	

    /**
     * @deprecated As of JDK version 1.1,
     * replaced by <code>setLocation(int, int)</code>.
     */
    public void move(int x, int y) {
	this.x = x;
	this.y = y;
    }	

    /**
     * Translates the rectangle the indicated distance,
     * to the right along the <i>x</i> coordinate axis, and 
     * downward along the <i>y</i> coordinate axis.
     * @param     dx   the distance to move the rectangle 
     *                 along the <i>x</i> axis.
     * @param     dy   the distance to move the rectangle 
     *                 along the <i>y</i> axis.
     * @see       java.awt.Rectangle#setLocation(int, int)
     * @see       java.awt.Rectangle#setLocation(java.awt.Point)
     * @since     JDK1.0
     */
    public void translate(int x, int y) {