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25  package java.awt;
26  
27  import java.io.*;
28  import java.lang.*;
29  import java.util.*;
30  import java.awt.image.ImageObserver;
31  import java.text.AttributedCharacterIterator;
32  
33  /**
34   * The <code>Graphics</code> class is the abstract base class for
35   * all graphics contexts that allow an application to draw onto
36   * components that are realized on various devices, as well as
37   * onto off-screen images.
38   * <p>
39   * A <code>Graphics</code> object encapsulates state information needed
40   * for the basic rendering operations that Java supports.  This
41   * state information includes the following properties:
42   *
43   * <ul>
44   * <li>The <code>Component</code> object on which to draw.
45   * <li>A translation origin for rendering and clipping coordinates.
46   * <li>The current clip.
47   * <li>The current color.
48   * <li>The current font.
49   * <li>The current logical pixel operation function (XOR or Paint).
50   * <li>The current XOR alternation color
51   *     (see {@link Graphics#setXORMode}).
52   * </ul>
53   * <p>
54   * Coordinates are infinitely thin and lie between the pixels of the
55   * output device.
56   * Operations that draw the outline of a figure operate by traversing
57   * an infinitely thin path between pixels with a pixel-sized pen that hangs
58   * down and to the right of the anchor point on the path.
59   * Operations that fill a figure operate by filling the interior
60   * of that infinitely thin path.
61   * Operations that render horizontal text render the ascending
62   * portion of character glyphs entirely above the baseline coordinate.
63   * <p>
64   * The graphics pen hangs down and to the right from the path it traverses.
65   * This has the following implications:
66   * <ul>
67   * <li>If you draw a figure that covers a given rectangle, that
68   * figure occupies one extra row of pixels on the right and bottom edges
69   * as compared to filling a figure that is bounded by that same rectangle.
70   * <li>If you draw a horizontal line along the same <i>y</i> coordinate as
71   * the baseline of a line of text, that line is drawn entirely below
72   * the text, except for any descenders.
73   * </ul><p>
74   * All coordinates that appear as arguments to the methods of this
75   * <code>Graphics</code> object are considered relative to the
76   * translation origin of this <code>Graphics</code> object prior to
77   * the invocation of the method.
78   * <p>
79   * All rendering operations modify only pixels which lie within the
80   * area bounded by the current clip, which is specified by a {@link Shape}
81   * in user space and is controlled by the program using the
82   * <code>Graphics</code> object.  This <i>user clip</i>
83   * is transformed into device space and combined with the
84   * <i>device clip</i>, which is defined by the visibility of windows and
85   * device extents.  The combination of the user clip and device clip
86   * defines the <i>composite clip</i>, which determines the final clipping
87   * region.  The user clip cannot be modified by the rendering
88   * system to reflect the resulting composite clip. The user clip can only
89   * be changed through the <code>setClip</code> or <code>clipRect</code>
90   * methods.
91   * All drawing or writing is done in the current color,
92   * using the current paint mode, and in the current font.
93   *
94   * @author      Sami Shaio
95   * @author      Arthur van Hoff
96   * @see     java.awt.Component
97   * @see     java.awt.Graphics#clipRect(int, int, int, int)
98   * @see     java.awt.Graphics#setColor(java.awt.Color)
99   * @see     java.awt.Graphics#setPaintMode()
100  * @see     java.awt.Graphics#setXORMode(java.awt.Color)
101  * @see     java.awt.Graphics#setFont(java.awt.Font)
102  * @since       JDK1.0
103  */
104 public abstract class Graphics {
105 
106     /**
107      * Constructs a new <code>Graphics</code> object.
108      * This constructor is the default constructor for a graphics
109      * context.
110      * <p>
111      * Since <code>Graphics</code> is an abstract class, applications
112      * cannot call this constructor directly. Graphics contexts are
113      * obtained from other graphics contexts or are created by calling
114      * <code>getGraphics</code> on a component.
115      * @see        java.awt.Graphics#create()
116      * @see        java.awt.Component#getGraphics
117      */
118     protected Graphics() {
119     }
120 
121     /**
122      * Creates a new <code>Graphics</code> object that is
123      * a copy of this <code>Graphics</code> object.
124      * @return     a new graphics context that is a copy of
125      *                       this graphics context.
126      */
127     public abstract Graphics create();
128 
129     /**
130      * Creates a new <code>Graphics</code> object based on this
131      * <code>Graphics</code> object, but with a new translation and clip area.
132      * The new <code>Graphics</code> object has its origin
133      * translated to the specified point (<i>x</i>,&nbsp;<i>y</i>).
134      * Its clip area is determined by the intersection of the original
135      * clip area with the specified rectangle.  The arguments are all
136      * interpreted in the coordinate system of the original
137      * <code>Graphics</code> object. The new graphics context is
138      * identical to the original, except in two respects:
139      *
140      * <ul>
141      * <li>
142      * The new graphics context is translated by (<i>x</i>,&nbsp;<i>y</i>).
143      * That is to say, the point (<code>0</code>,&nbsp;<code>0</code>) in the
144      * new graphics context is the same as (<i>x</i>,&nbsp;<i>y</i>) in
145      * the original graphics context.
146      * <li>
147      * The new graphics context has an additional clipping rectangle, in
148      * addition to whatever (translated) clipping rectangle it inherited
149      * from the original graphics context. The origin of the new clipping
150      * rectangle is at (<code>0</code>,&nbsp;<code>0</code>), and its size
151      * is specified by the <code>width</code> and <code>height</code>
152      * arguments.
153      * </ul>
154      * <p>
155      * @param      x   the <i>x</i> coordinate.
156      * @param      y   the <i>y</i> coordinate.
157      * @param      width   the width of the clipping rectangle.
158      * @param      height   the height of the clipping rectangle.
159      * @return     a new graphics context.
160      * @see        java.awt.Graphics#translate
161      * @see        java.awt.Graphics#clipRect
162      */
163     public Graphics create(int x, int y, int width, int height) {
164         Graphics g = create();
165         if (g == null) return null;
166         g.translate(x, y);
167         g.clipRect(0, 0, width, height);
168         return g;
169     }
170 
171     /**
172      * Translates the origin of the graphics context to the point
173      * (<i>x</i>,&nbsp;<i>y</i>) in the current coordinate system.
174      * Modifies this graphics context so that its new origin corresponds
175      * to the point (<i>x</i>,&nbsp;<i>y</i>) in this graphics context's
176      * original coordinate system.  All coordinates used in subsequent
177      * rendering operations on this graphics context will be relative
178      * to this new origin.
179      * @param  x   the <i>x</i> coordinate.
180      * @param  y   the <i>y</i> coordinate.
181      */
182     public abstract void translate(int x, int y);
183 
184     /**
185      * Gets this graphics context's current color.
186      * @return    this graphics context's current color.
187      * @see       java.awt.Color
188      * @see       java.awt.Graphics#setColor(Color)
189      */
190     public abstract Color getColor();
191 
192     /**
193      * Sets this graphics context's current color to the specified
194      * color. All subsequent graphics operations using this graphics
195      * context use this specified color.
196      * @param     c   the new rendering color.
197      * @see       java.awt.Color
198      * @see       java.awt.Graphics#getColor
199      */
200     public abstract void setColor(Color c);
201 
202     /**
203      * Sets the paint mode of this graphics context to overwrite the
204      * destination with this graphics context's current color.
205      * This sets the logical pixel operation function to the paint or
206      * overwrite mode.  All subsequent rendering operations will
207      * overwrite the destination with the current color.
208      */
209     public abstract void setPaintMode();
210 
211     /**
212      * Sets the paint mode of this graphics context to alternate between
213      * this graphics context's current color and the new specified color.
214      * This specifies that logical pixel operations are performed in the
215      * XOR mode, which alternates pixels between the current color and
216      * a specified XOR color.
217      * <p>
218      * When drawing operations are performed, pixels which are the
219      * current color are changed to the specified color, and vice versa.
220      * <p>
221      * Pixels that are of colors other than those two colors are changed
222      * in an unpredictable but reversible manner; if the same figure is
223      * drawn twice, then all pixels are restored to their original values.
224      * @param     c1 the XOR alternation color
225      */
226     public abstract void setXORMode(Color c1);
227 
228     /**
229      * Gets the current font.
230      * @return    this graphics context's current font.
231      * @see       java.awt.Font
232      * @see       java.awt.Graphics#setFont(Font)
233      */
234     public abstract Font getFont();
235 
236     /**
237      * Sets this graphics context's font to the specified font.
238      * All subsequent text operations using this graphics context
239      * use this font. A null argument is silently ignored.
240      * @param  font   the font.
241      * @see     java.awt.Graphics#getFont
242      * @see     java.awt.Graphics#drawString(java.lang.String, int, int)
243      * @see     java.awt.Graphics#drawBytes(byte[], int, int, int, int)
244      * @see     java.awt.Graphics#drawChars(char[], int, int, int, int)
245     */
246     public abstract void setFont(Font font);
247 
248     /**
249      * Gets the font metrics of the current font.
250      * @return    the font metrics of this graphics
251      *                    context's current font.
252      * @see       java.awt.Graphics#getFont
253      * @see       java.awt.FontMetrics
254      * @see       java.awt.Graphics#getFontMetrics(Font)
255      */
256     public FontMetrics getFontMetrics() {
257         return getFontMetrics(getFont());
258     }
259 
260     /**
261      * Gets the font metrics for the specified font.
262      * @return    the font metrics for the specified font.
263      * @param     f the specified font
264      * @see       java.awt.Graphics#getFont
265      * @see       java.awt.FontMetrics
266      * @see       java.awt.Graphics#getFontMetrics()
267      */
268     public abstract FontMetrics getFontMetrics(Font f);
269 
270 
271     /**
272      * Returns the bounding rectangle of the current clipping area.
273      * This method refers to the user clip, which is independent of the
274      * clipping associated with device bounds and window visibility.
275      * If no clip has previously been set, or if the clip has been
276      * cleared using <code>setClip(null)</code>, this method returns
277      * <code>null</code>.
278      * The coordinates in the rectangle are relative to the coordinate
279      * system origin of this graphics context.
280      * @return      the bounding rectangle of the current clipping area,
281      *              or <code>null</code> if no clip is set.
282      * @see         java.awt.Graphics#getClip
283      * @see         java.awt.Graphics#clipRect
284      * @see         java.awt.Graphics#setClip(int, int, int, int)
285      * @see         java.awt.Graphics#setClip(Shape)
286      * @since       JDK1.1
287      */
288     public abstract Rectangle getClipBounds();
289 
290     /**
291      * Intersects the current clip with the specified rectangle.
292      * The resulting clipping area is the intersection of the current
293      * clipping area and the specified rectangle.  If there is no
294      * current clipping area, either because the clip has never been
295      * set, or the clip has been cleared using <code>setClip(null)</code>,
296      * the specified rectangle becomes the new clip.
297      * This method sets the user clip, which is independent of the
298      * clipping associated with device bounds and window visibility.
299      * This method can only be used to make the current clip smaller.
300      * To set the current clip larger, use any of the setClip methods.
301      * Rendering operations have no effect outside of the clipping area.
302      * @param x the x coordinate of the rectangle to intersect the clip with
303      * @param y the y coordinate of the rectangle to intersect the clip with
304      * @param width the width of the rectangle to intersect the clip with
305      * @param height the height of the rectangle to intersect the clip with
306      * @see #setClip(int, int, int, int)
307      * @see #setClip(Shape)
308      */
309     public abstract void clipRect(int x, int y, int width, int height);
310 
311     /**
312      * Sets the current clip to the rectangle specified by the given
313      * coordinates.  This method sets the user clip, which is
314      * independent of the clipping associated with device bounds
315      * and window visibility.
316      * Rendering operations have no effect outside of the clipping area.
317      * @param       x the <i>x</i> coordinate of the new clip rectangle.
318      * @param       y the <i>y</i> coordinate of the new clip rectangle.
319      * @param       width the width of the new clip rectangle.
320      * @param       height the height of the new clip rectangle.
321      * @see         java.awt.Graphics#clipRect
322      * @see         java.awt.Graphics#setClip(Shape)
323      * @see         java.awt.Graphics#getClip
324      * @since       JDK1.1
325      */
326     public abstract void setClip(int x, int y, int width, int height);
327 
328     /**
329      * Gets the current clipping area.
330      * This method returns the user clip, which is independent of the
331      * clipping associated with device bounds and window visibility.
332      * If no clip has previously been set, or if the clip has been
333      * cleared using <code>setClip(null)</code>, this method returns
334      * <code>null</code>.
335      * @return      a <code>Shape</code> object representing the
336      *              current clipping area, or <code>null</code> if
337      *              no clip is set.
338      * @see         java.awt.Graphics#getClipBounds
339      * @see         java.awt.Graphics#clipRect
340      * @see         java.awt.Graphics#setClip(int, int, int, int)
341      * @see         java.awt.Graphics#setClip(Shape)
342      * @since       JDK1.1
343      */
344     public abstract Shape getClip();
345 
346     /**
347      * Sets the current clipping area to an arbitrary clip shape.
348      * Not all objects that implement the <code>Shape</code>
349      * interface can be used to set the clip.  The only
350      * <code>Shape</code> objects that are guaranteed to be
351      * supported are <code>Shape</code> objects that are
352      * obtained via the <code>getClip</code> method and via
353      * <code>Rectangle</code> objects.  This method sets the
354      * user clip, which is independent of the clipping associated
355      * with device bounds and window visibility.
356      * @param clip the <code>Shape</code> to use to set the clip
357      * @see         java.awt.Graphics#getClip()
358      * @see         java.awt.Graphics#clipRect
359      * @see         java.awt.Graphics#setClip(int, int, int, int)
360      * @since       JDK1.1
361      */
362     public abstract void setClip(Shape clip);
363 
364     /**
365      * Copies an area of the component by a distance specified by
366      * <code>dx</code> and <code>dy</code>. From the point specified
367      * by <code>x</code> and <code>y</code>, this method
368      * copies downwards and to the right.  To copy an area of the
369      * component to the left or upwards, specify a negative value for
370      * <code>dx</code> or <code>dy</code>.
371      * If a portion of the source rectangle lies outside the bounds
372      * of the component, or is obscured by another window or component,
373      * <code>copyArea</code> will be unable to copy the associated
374      * pixels. The area that is omitted can be refreshed by calling
375      * the component's <code>paint</code> method.
376      * @param       x the <i>x</i> coordinate of the source rectangle.
377      * @param       y the <i>y</i> coordinate of the source rectangle.
378      * @param       width the width of the source rectangle.
379      * @param       height the height of the source rectangle.
380      * @param       dx the horizontal distance to copy the pixels.
381      * @param       dy the vertical distance to copy the pixels.
382      */
383     public abstract void copyArea(int x, int y, int width, int height,
384                                   int dx, int dy);
385 
386     /**
387      * Draws a line, using the current color, between the points
388      * <code>(x1,&nbsp;y1)</code> and <code>(x2,&nbsp;y2)</code>
389      * in this graphics context's coordinate system.
390      * @param   x1  the first point's <i>x</i> coordinate.
391      * @param   y1  the first point's <i>y</i> coordinate.
392      * @param   x2  the second point's <i>x</i> coordinate.
393      * @param   y2  the second point's <i>y</i> coordinate.
394      */
395     public abstract void drawLine(int x1, int y1, int x2, int y2);
396 
397     /**
398      * Fills the specified rectangle.
399      * The left and right edges of the rectangle are at
400      * <code>x</code> and <code>x&nbsp;+&nbsp;width&nbsp;-&nbsp;1</code>.
401      * The top and bottom edges are at
402      * <code>y</code> and <code>y&nbsp;+&nbsp;height&nbsp;-&nbsp;1</code>.
403      * The resulting rectangle covers an area
404      * <code>width</code> pixels wide by
405      * <code>height</code> pixels tall.
406      * The rectangle is filled using the graphics context's current color.
407      * @param         x   the <i>x</i> coordinate
408      *                         of the rectangle to be filled.
409      * @param         y   the <i>y</i> coordinate
410      *                         of the rectangle to be filled.
411      * @param         width   the width of the rectangle to be filled.
412      * @param         height   the height of the rectangle to be filled.
413      * @see           java.awt.Graphics#clearRect
414      * @see           java.awt.Graphics#drawRect
415      */
416     public abstract void fillRect(int x, int y, int width, int height);
417 
418     /**
419      * Draws the outline of the specified rectangle.
420      * The left and right edges of the rectangle are at
421      * <code>x</code> and <code>x&nbsp;+&nbsp;width</code>.
422      * The top and bottom edges are at
423      * <code>y</code> and <code>y&nbsp;+&nbsp;height</code>.
424      * The rectangle is drawn using the graphics context's current color.
425      * @param         x   the <i>x</i> coordinate
426      *                         of the rectangle to be drawn.
427      * @param         y   the <i>y</i> coordinate
428      *                         of the rectangle to be drawn.
429      * @param         width   the width of the rectangle to be drawn.
430      * @param         height   the height of the rectangle to be drawn.
431      * @see          java.awt.Graphics#fillRect
432      * @see          java.awt.Graphics#clearRect
433      */
434     public void drawRect(int x, int y, int width, int height) {
435         if ((width < 0) || (height < 0)) {
436             return;
437         }
438 
439         if (height == 0 || width == 0) {
440             drawLine(x, y, x + width, y + height);
441         } else {
442             drawLine(x, y, x + width - 1, y);
443             drawLine(x + width, y, x + width, y + height - 1);
444             drawLine(x + width, y + height, x + 1, y + height);
445             drawLine(x, y + height, x, y + 1);
446         }
447     }
448 
449     /**
450      * Clears the specified rectangle by filling it with the background
451      * color of the current drawing surface. This operation does not
452      * use the current paint mode.
453      * <p>
454      * Beginning with Java&nbsp;1.1, the background color
455      * of offscreen images may be system dependent. Applications should
456      * use <code>setColor</code> followed by <code>fillRect</code> to
457      * ensure that an offscreen image is cleared to a specific color.
458      * @param       x the <i>x</i> coordinate of the rectangle to clear.
459      * @param       y the <i>y</i> coordinate of the rectangle to clear.
460      * @param       width the width of the rectangle to clear.
461      * @param       height the height of the rectangle to clear.
462      * @see         java.awt.Graphics#fillRect(int, int, int, int)
463      * @see         java.awt.Graphics#drawRect
464      * @see         java.awt.Graphics#setColor(java.awt.Color)
465      * @see         java.awt.Graphics#setPaintMode
466      * @see         java.awt.Graphics#setXORMode(java.awt.Color)
467      */
468     public abstract void clearRect(int x, int y, int width, int height);
469 
470     /**
471      * Draws an outlined round-cornered rectangle using this graphics
472      * context's current color. The left and right edges of the rectangle
473      * are at <code>x</code> and <code>x&nbsp;+&nbsp;width</code>,
474      * respectively. The top and bottom edges of the rectangle are at
475      * <code>y</code> and <code>y&nbsp;+&nbsp;height</code>.
476      * @param      x the <i>x</i> coordinate of the rectangle to be drawn.
477      * @param      y the <i>y</i> coordinate of the rectangle to be drawn.
478      * @param      width the width of the rectangle to be drawn.
479      * @param      height the height of the rectangle to be drawn.
480      * @param      arcWidth the horizontal diameter of the arc
481      *                    at the four corners.
482      * @param      arcHeight the vertical diameter of the arc
483      *                    at the four corners.
484      * @see        java.awt.Graphics#fillRoundRect
485      */
486     public abstract void drawRoundRect(int x, int y, int width, int height,
487                                        int arcWidth, int arcHeight);
488 
489     /**
490      * Fills the specified rounded corner rectangle with the current color.
491      * The left and right edges of the rectangle
492      * are at <code>x</code> and <code>x&nbsp;+&nbsp;width&nbsp;-&nbsp;1</code>,
493      * respectively. The top and bottom edges of the rectangle are at
494      * <code>y</code> and <code>y&nbsp;+&nbsp;height&nbsp;-&nbsp;1</code>.
495      * @param       x the <i>x</i> coordinate of the rectangle to be filled.
496      * @param       y the <i>y</i> coordinate of the rectangle to be filled.
497      * @param       width the width of the rectangle to be filled.
498      * @param       height the height of the rectangle to be filled.
499      * @param       arcWidth the horizontal diameter
500      *                     of the arc at the four corners.
501      * @param       arcHeight the vertical diameter
502      *                     of the arc at the four corners.
503      * @see         java.awt.Graphics#drawRoundRect
504      */
505     public abstract void fillRoundRect(int x, int y, int width, int height,
506                                        int arcWidth, int arcHeight);
507 
508     /**
509      * Draws a 3-D highlighted outline of the specified rectangle.
510      * The edges of the rectangle are highlighted so that they
511      * appear to be beveled and lit from the upper left corner.
512      * <p>
513      * The colors used for the highlighting effect are determined
514      * based on the current color.
515      * The resulting rectangle covers an area that is
516      * <code>width&nbsp;+&nbsp;1</code> pixels wide
517      * by <code>height&nbsp;+&nbsp;1</code> pixels tall.
518      * @param       x the <i>x</i> coordinate of the rectangle to be drawn.
519      * @param       y the <i>y</i> coordinate of the rectangle to be drawn.
520      * @param       width the width of the rectangle to be drawn.
521      * @param       height the height of the rectangle to be drawn.
522      * @param       raised a boolean that determines whether the rectangle
523      *                      appears to be raised above the surface
524      *                      or sunk into the surface.
525      * @see         java.awt.Graphics#fill3DRect
526      */
527     public void draw3DRect(int x, int y, int width, int height,
528                            boolean raised) {
529         Color c = getColor();
530         Color brighter = c.brighter();
531         Color darker = c.darker();
532 
533         setColor(raised ? brighter : darker);
534         drawLine(x, y, x, y + height);
535         drawLine(x + 1, y, x + width - 1, y);
536         setColor(raised ? darker : brighter);
537         drawLine(x + 1, y + height, x + width, y + height);
538         drawLine(x + width, y, x + width, y + height - 1);
539         setColor(c);
540     }
541 
542     /**
543      * Paints a 3-D highlighted rectangle filled with the current color.
544      * The edges of the rectangle will be highlighted so that it appears
545      * as if the edges were beveled and lit from the upper left corner.
546      * The colors used for the highlighting effect will be determined from
547      * the current color.
548      * @param       x the <i>x</i> coordinate of the rectangle to be filled.
549      * @param       y the <i>y</i> coordinate of the rectangle to be filled.
550      * @param       width the width of the rectangle to be filled.
551      * @param       height the height of the rectangle to be filled.
552      * @param       raised a boolean value that determines whether the
553      *                      rectangle appears to be raised above the surface
554      *                      or etched into the surface.
555      * @see         java.awt.Graphics#draw3DRect
556      */
557     public void fill3DRect(int x, int y, int width, int height,
558                            boolean raised) {
559         Color c = getColor();
560         Color brighter = c.brighter();
561         Color darker = c.darker();
562 
563         if (!raised) {
564             setColor(darker);
565         }
566         fillRect(x+1, y+1, width-2, height-2);
567         setColor(raised ? brighter : darker);
568         drawLine(x, y, x, y + height - 1);
569         drawLine(x + 1, y, x + width - 2, y);
570         setColor(raised ? darker : brighter);
571         drawLine(x + 1, y + height - 1, x + width - 1, y + height - 1);
572         drawLine(x + width - 1, y, x + width - 1, y + height - 2);
573         setColor(c);
574     }
575 
576     /**
577      * Draws the outline of an oval.
578      * The result is a circle or ellipse that fits within the
579      * rectangle specified by the <code>x</code>, <code>y</code>,
580      * <code>width</code>, and <code>height</code> arguments.
581      * <p>
582      * The oval covers an area that is
583      * <code>width&nbsp;+&nbsp;1</code> pixels wide
584      * and <code>height&nbsp;+&nbsp;1</code> pixels tall.
585      * @param       x the <i>x</i> coordinate of the upper left
586      *                     corner of the oval to be drawn.
587      * @param       y the <i>y</i> coordinate of the upper left
588      *                     corner of the oval to be drawn.
589      * @param       width the width of the oval to be drawn.
590      * @param       height the height of the oval to be drawn.
591      * @see         java.awt.Graphics#fillOval
592      */
593     public abstract void drawOval(int x, int y, int width, int height);
594 
595     /**
596      * Fills an oval bounded by the specified rectangle with the
597      * current color.
598      * @param       x the <i>x</i> coordinate of the upper left corner
599      *                     of the oval to be filled.
600      * @param       y the <i>y</i> coordinate of the upper left corner
601      *                     of the oval to be filled.
602      * @param       width the width of the oval to be filled.
603      * @param       height the height of the oval to be filled.
604      * @see         java.awt.Graphics#drawOval
605      */
606     public abstract void fillOval(int x, int y, int width, int height);
607 
608     /**
609      * Draws the outline of a circular or elliptical arc
610      * covering the specified rectangle.
611      * <p>
612      * The resulting arc begins at <code>startAngle</code> and extends
613      * for <code>arcAngle</code> degrees, using the current color.
614      * Angles are interpreted such that 0&nbsp;degrees
615      * is at the 3&nbsp;o'clock position.
616      * A positive value indicates a counter-clockwise rotation
617      * while a negative value indicates a clockwise rotation.
618      * <p>
619      * The center of the arc is the center of the rectangle whose origin
620      * is (<i>x</i>,&nbsp;<i>y</i>) and whose size is specified by the
621      * <code>width</code> and <code>height</code> arguments.
622      * <p>
623      * The resulting arc covers an area
624      * <code>width&nbsp;+&nbsp;1</code> pixels wide
625      * by <code>height&nbsp;+&nbsp;1</code> pixels tall.
626      * <p>
627      * The angles are specified relative to the non-square extents of
628      * the bounding rectangle such that 45 degrees always falls on the
629      * line from the center of the ellipse to the upper right corner of
630      * the bounding rectangle. As a result, if the bounding rectangle is
631      * noticeably longer in one axis than the other, the angles to the
632      * start and end of the arc segment will be skewed farther along the
633      * longer axis of the bounds.
634      * @param        x the <i>x</i> coordinate of the
635      *                    upper-left corner of the arc to be drawn.
636      * @param        y the <i>y</i>  coordinate of the
637      *                    upper-left corner of the arc to be drawn.
638      * @param        width the width of the arc to be drawn.
639      * @param        height the height of the arc to be drawn.
640      * @param        startAngle the beginning angle.
641      * @param        arcAngle the angular extent of the arc,
642      *                    relative to the start angle.
643      * @see         java.awt.Graphics#fillArc
644      */
645     public abstract void drawArc(int x, int y, int width, int height,
646                                  int startAngle, int arcAngle);
647 
648     /**
649      * Fills a circular or elliptical arc covering the specified rectangle.
650      * <p>
651      * The resulting arc begins at <code>startAngle</code> and extends
652      * for <code>arcAngle</code> degrees.
653      * Angles are interpreted such that 0&nbsp;degrees
654      * is at the 3&nbsp;o'clock position.
655      * A positive value indicates a counter-clockwise rotation
656      * while a negative value indicates a clockwise rotation.
657      * <p>
658      * The center of the arc is the center of the rectangle whose origin
659      * is (<i>x</i>,&nbsp;<i>y</i>) and whose size is specified by the
660      * <code>width</code> and <code>height</code> arguments.
661      * <p>
662      * The resulting arc covers an area
663      * <code>width&nbsp;+&nbsp;1</code> pixels wide
664      * by <code>height&nbsp;+&nbsp;1</code> pixels tall.
665      * <p>
666      * The angles are specified relative to the non-square extents of
667      * the bounding rectangle such that 45 degrees always falls on the
668      * line from the center of the ellipse to the upper right corner of
669      * the bounding rectangle. As a result, if the bounding rectangle is
670      * noticeably longer in one axis than the other, the angles to the
671      * start and end of the arc segment will be skewed farther along the
672      * longer axis of the bounds.
673      * @param        x the <i>x</i> coordinate of the
674      *                    upper-left corner of the arc to be filled.
675      * @param        y the <i>y</i>  coordinate of the
676      *                    upper-left corner of the arc to be filled.
677      * @param        width the width of the arc to be filled.
678      * @param        height the height of the arc to be filled.
679      * @param        startAngle the beginning angle.
680      * @param        arcAngle the angular extent of the arc,
681      *                    relative to the start angle.
682      * @see         java.awt.Graphics#drawArc
683      */
684     public abstract void fillArc(int x, int y, int width, int height,
685                                  int startAngle, int arcAngle);
686 
687     /**
688      * Draws a sequence of connected lines defined by
689      * arrays of <i>x</i> and <i>y</i> coordinates.
690      * Each pair of (<i>x</i>,&nbsp;<i>y</i>) coordinates defines a point.
691      * The figure is not closed if the first point
692      * differs from the last point.
693      * @param       xPoints an array of <i>x</i> points
694      * @param       yPoints an array of <i>y</i> points
695      * @param       nPoints the total number of points
696      * @see         java.awt.Graphics#drawPolygon(int[], int[], int)
697      * @since       JDK1.1
698      */
699     public abstract void drawPolyline(int xPoints[], int yPoints[],
700                                       int nPoints);
701 
702     /**
703      * Draws a closed polygon defined by
704      * arrays of <i>x</i> and <i>y</i> coordinates.
705      * Each pair of (<i>x</i>,&nbsp;<i>y</i>) coordinates defines a point.
706      * <p>
707      * This method draws the polygon defined by <code>nPoint</code> line
708      * segments, where the first <code>nPoint&nbsp;-&nbsp;1</code>
709      * line segments are line segments from
710      * <code>(xPoints[i&nbsp;-&nbsp;1],&nbsp;yPoints[i&nbsp;-&nbsp;1])</code>
711      * to <code>(xPoints[i],&nbsp;yPoints[i])</code>, for
712      * 1&nbsp;&le;&nbsp;<i>i</i>&nbsp;&le;&nbsp;<code>nPoints</code>.
713      * The figure is automatically closed by drawing a line connecting
714      * the final point to the first point, if those points are different.
715      * @param        xPoints   a an array of <code>x</code> coordinates.
716      * @param        yPoints   a an array of <code>y</code> coordinates.
717      * @param        nPoints   a the total number of points.
718      * @see          java.awt.Graphics#fillPolygon
719      * @see          java.awt.Graphics#drawPolyline
720      */
721     public abstract void drawPolygon(int xPoints[], int yPoints[],
722                                      int nPoints);
723 
724     /**
725      * Draws the outline of a polygon defined by the specified
726      * <code>Polygon</code> object.
727      * @param        p the polygon to draw.
728      * @see          java.awt.Graphics#fillPolygon
729      * @see          java.awt.Graphics#drawPolyline
730      */
731     public void drawPolygon(Polygon p) {
732         drawPolygon(p.xpoints, p.ypoints, p.npoints);
733     }
734 
735     /**
736      * Fills a closed polygon defined by
737      * arrays of <i>x</i> and <i>y</i> coordinates.
738      * <p>
739      * This method draws the polygon defined by <code>nPoint</code> line
740      * segments, where the first <code>nPoint&nbsp;-&nbsp;1</code>
741      * line segments are line segments from
742      * <code>(xPoints[i&nbsp;-&nbsp;1],&nbsp;yPoints[i&nbsp;-&nbsp;1])</code>
743      * to <code>(xPoints[i],&nbsp;yPoints[i])</code>, for
744      * 1&nbsp;&le;&nbsp;<i>i</i>&nbsp;&le;&nbsp;<code>nPoints</code>.
745      * The figure is automatically closed by drawing a line connecting
746      * the final point to the first point, if those points are different.
747      * <p>
748      * The area inside the polygon is defined using an
749      * even-odd fill rule, also known as the alternating rule.
750      * @param        xPoints   a an array of <code>x</code> coordinates.
751      * @param        yPoints   a an array of <code>y</code> coordinates.
752      * @param        nPoints   a the total number of points.
753      * @see          java.awt.Graphics#drawPolygon(int[], int[], int)
754      */
755     public abstract void fillPolygon(int xPoints[], int yPoints[],
756                                      int nPoints);
757 
758     /**
759      * Fills the polygon defined by the specified Polygon object with
760      * the graphics context's current color.
761      * <p>
762      * The area inside the polygon is defined using an
763      * even-odd fill rule, also known as the alternating rule.
764      * @param        p the polygon to fill.
765      * @see          java.awt.Graphics#drawPolygon(int[], int[], int)
766      */
767     public void fillPolygon(Polygon p) {
768         fillPolygon(p.xpoints, p.ypoints, p.npoints);
769     }
770 
771     /**
772      * Draws the text given by the specified string, using this
773      * graphics context's current font and color. The baseline of the
774      * leftmost character is at position (<i>x</i>,&nbsp;<i>y</i>) in this
775      * graphics context's coordinate system.
776      * @param       str      the string to be drawn.
777      * @param       x        the <i>x</i> coordinate.
778      * @param       y        the <i>y</i> coordinate.
779      * @throws NullPointerException if <code>str</code> is <code>null</code>.
780      * @see         java.awt.Graphics#drawBytes
781      * @see         java.awt.Graphics#drawChars
782      */
783     public abstract void drawString(String str, int x, int y);
784 
785     /**
786      * Renders the text of the specified iterator applying its attributes
787      * in accordance with the specification of the
788      * {@link java.awt.font.TextAttribute TextAttribute} class.
789      * <p>
790      * The baseline of the leftmost character is at position
791      * (<i>x</i>,&nbsp;<i>y</i>) in this graphics context's coordinate system.
792      * @param       iterator the iterator whose text is to be drawn
793      * @param       x        the <i>x</i> coordinate.
794      * @param       y        the <i>y</i> coordinate.
795      * @throws NullPointerException if <code>iterator</code> is
796      * <code>null</code>.
797      * @see         java.awt.Graphics#drawBytes
798      * @see         java.awt.Graphics#drawChars
799      */
800    public abstract void drawString(AttributedCharacterIterator iterator,
801                                     int x, int y);
802 
803     /**
804      * Draws the text given by the specified character array, using this
805      * graphics context's current font and color. The baseline of the
806      * first character is at position (<i>x</i>,&nbsp;<i>y</i>) in this
807      * graphics context's coordinate system.
808      * @param data the array of characters to be drawn
809      * @param offset the start offset in the data
810      * @param length the number of characters to be drawn
811      * @param x the <i>x</i> coordinate of the baseline of the text
812      * @param y the <i>y</i> coordinate of the baseline of the text
813      * @throws NullPointerException if <code>data</code> is <code>null</code>.
814      * @throws IndexOutOfBoundsException if <code>offset</code> or
815      * <code>length</code>is less than zero, or
816      * <code>offset+length</code> is greater than the length of the
817      * <code>data</code> array.
818      * @see         java.awt.Graphics#drawBytes
819      * @see         java.awt.Graphics#drawString
820      */
821     public void drawChars(char data[], int offset, int length, int x, int y) {
822         drawString(new String(data, offset, length), x, y);
823     }
824 
825     /**
826      * Draws the text given by the specified byte array, using this
827      * graphics context's current font and color. The baseline of the
828      * first character is at position (<i>x</i>,&nbsp;<i>y</i>) in this
829      * graphics context's coordinate system.
830      * <p>
831      * Use of this method is not recommended as each byte is interpreted
832      * as a Unicode code point in the range 0 to 255, and so can only be
833      * used to draw Latin characters in that range.
834      * @param data the data to be drawn
835      * @param offset the start offset in the data
836      * @param length the number of bytes that are drawn
837      * @param x the <i>x</i> coordinate of the baseline of the text
838      * @param y the <i>y</i> coordinate of the baseline of the text
839      * @throws NullPointerException if <code>data</code> is <code>null</code>.
840      * @throws IndexOutOfBoundsException if <code>offset</code> or
841      * <code>length</code>is less than zero, or <code>offset+length</code>
842      * is greater than the length of the <code>data</code> array.
843      * @see         java.awt.Graphics#drawChars
844      * @see         java.awt.Graphics#drawString
845      */
846     public void drawBytes(byte data[], int offset, int length, int x, int y) {
847         drawString(new String(data, 0, offset, length), x, y);
848     }
849 
850     /**
851      * Draws as much of the specified image as is currently available.
852      * The image is drawn with its top-left corner at
853      * (<i>x</i>,&nbsp;<i>y</i>) in this graphics context's coordinate
854      * space. Transparent pixels in the image do not affect whatever
855      * pixels are already there.
856      * <p>
857      * This method returns immediately in all cases, even if the
858      * complete image has not yet been loaded, and it has not been dithered
859      * and converted for the current output device.
860      * <p>
861      * If the image has completely loaded and its pixels are
862      * no longer being changed, then
863      * <code>drawImage</code> returns <code>true</code>.
864      * Otherwise, <code>drawImage</code> returns <code>false</code>
865      * and as more of
866      * the image becomes available
867      * or it is time to draw another frame of animation,
868      * the process that loads the image notifies
869      * the specified image observer.
870      * @param    img the specified image to be drawn. This method does
871      *               nothing if <code>img</code> is null.
872      * @param    x   the <i>x</i> coordinate.
873      * @param    y   the <i>y</i> coordinate.
874      * @param    observer    object to be notified as more of
875      *                          the image is converted.
876      * @return   <code>false</code> if the image pixels are still changing;
877      *           <code>true</code> otherwise.
878      * @see      java.awt.Image
879      * @see      java.awt.image.ImageObserver
880      * @see      java.awt.image.ImageObserver#imageUpdate(java.awt.Image, int, int, int, int, int)
881      */
882     public abstract boolean drawImage(Image img, int x, int y,
883                                       ImageObserver observer);
884 
885     /**
886      * Draws as much of the specified image as has already been scaled
887      * to fit inside the specified rectangle.
888      * <p>
889      * The image is drawn inside the specified rectangle of this
890      * graphics context's coordinate space, and is scaled if
891      * necessary. Transparent pixels do not affect whatever pixels
892      * are already there.
893      * <p>
894      * This method returns immediately in all cases, even if the
895      * entire image has not yet been scaled, dithered, and converted
896      * for the current output device.
897      * If the current output representation is not yet complete, then
898      * <code>drawImage</code> returns <code>false</code>. As more of
899      * the image becomes available, the process that loads the image notifies
900      * the image observer by calling its <code>imageUpdate</code> method.
901      * <p>
902      * A scaled version of an image will not necessarily be
903      * available immediately just because an unscaled version of the
904      * image has been constructed for this output device.  Each size of
905      * the image may be cached separately and generated from the original
906      * data in a separate image production sequence.
907      * @param    img    the specified image to be drawn. This method does
908      *                  nothing if <code>img</code> is null.
909      * @param    x      the <i>x</i> coordinate.
910      * @param    y      the <i>y</i> coordinate.
911      * @param    width  the width of the rectangle.
912      * @param    height the height of the rectangle.
913      * @param    observer    object to be notified as more of
914      *                          the image is converted.
915      * @return   <code>false</code> if the image pixels are still changing;
916      *           <code>true</code> otherwise.
917      * @see      java.awt.Image
918      * @see      java.awt.image.ImageObserver
919      * @see      java.awt.image.ImageObserver#imageUpdate(java.awt.Image, int, int, int, int, int)
920      */
921     public abstract boolean drawImage(Image img, int x, int y,
922                                       int width, int height,
923                                       ImageObserver observer);
924 
925     /**
926      * Draws as much of the specified image as is currently available.
927      * The image is drawn with its top-left corner at
928      * (<i>x</i>,&nbsp;<i>y</i>) in this graphics context's coordinate
929      * space.  Transparent pixels are drawn in the specified
930      * background color.
931      * <p>
932      * This operation is equivalent to filling a rectangle of the
933      * width and height of the specified image with the given color and then
934      * drawing the image on top of it, but possibly more efficient.
935      * <p>
936      * This method returns immediately in all cases, even if the
937      * complete image has not yet been loaded, and it has not been dithered
938      * and converted for the current output device.
939      * <p>
940      * If the image has completely loaded and its pixels are
941      * no longer being changed, then
942      * <code>drawImage</code> returns <code>true</code>.
943      * Otherwise, <code>drawImage</code> returns <code>false</code>
944      * and as more of
945      * the image becomes available
946      * or it is time to draw another frame of animation,
947      * the process that loads the image notifies
948      * the specified image observer.
949      * @param    img the specified image to be drawn. This method does
950      *               nothing if <code>img</code> is null.
951      * @param    x      the <i>x</i> coordinate.
952      * @param    y      the <i>y</i> coordinate.
953      * @param    bgcolor the background color to paint under the
954      *                         non-opaque portions of the image.
955      * @param    observer    object to be notified as more of
956      *                          the image is converted.
957      * @return   <code>false</code> if the image pixels are still changing;
958      *           <code>true</code> otherwise.
959      * @see      java.awt.Image
960      * @see      java.awt.image.ImageObserver
961      * @see      java.awt.image.ImageObserver#imageUpdate(java.awt.Image, int, int, int, int, int)
962      */
963     public abstract boolean drawImage(Image img, int x, int y,
964                                       Color bgcolor,
965                                       ImageObserver observer);
966 
967     /**
968      * Draws as much of the specified image as has already been scaled
969      * to fit inside the specified rectangle.
970      * <p>
971      * The image is drawn inside the specified rectangle of this
972      * graphics context's coordinate space, and is scaled if
973      * necessary. Transparent pixels are drawn in the specified
974      * background color.
975      * This operation is equivalent to filling a rectangle of the
976      * width and height of the specified image with the given color and then
977      * drawing the image on top of it, but possibly more efficient.
978      * <p>
979      * This method returns immediately in all cases, even if the
980      * entire image has not yet been scaled, dithered, and converted
981      * for the current output device.
982      * If the current output representation is not yet complete then
983      * <code>drawImage</code> returns <code>false</code>. As more of
984      * the image becomes available, the process that loads the image notifies
985      * the specified image observer.
986      * <p>
987      * A scaled version of an image will not necessarily be
988      * available immediately just because an unscaled version of the
989      * image has been constructed for this output device.  Each size of
990      * the image may be cached separately and generated from the original
991      * data in a separate image production sequence.
992      * @param    img       the specified image to be drawn. This method does
993      *                     nothing if <code>img</code> is null.
994      * @param    x         the <i>x</i> coordinate.
995      * @param    y         the <i>y</i> coordinate.
996      * @param    width     the width of the rectangle.
997      * @param    height    the height of the rectangle.
998      * @param    bgcolor   the background color to paint under the
999      *                         non-opaque portions of the image.
1000      * @param    observer    object to be notified as more of
1001      *                          the image is converted.
1002      * @return   <code>false</code> if the image pixels are still changing;
1003      *           <code>true</code> otherwise.
1004      * @see      java.awt.Image
1005      * @see      java.awt.image.ImageObserver
1006      * @see      java.awt.image.ImageObserver#imageUpdate(java.awt.Image, int, int, int, int, int)
1007      */
1008     public abstract boolean drawImage(Image img, int x, int y,
1009                                       int width, int height,
1010                                       Color bgcolor,
1011                                       ImageObserver observer);
1012 
1013     /**
1014      * Draws as much of the specified area of the specified image as is
1015      * currently available, scaling it on the fly to fit inside the
1016      * specified area of the destination drawable surface. Transparent pixels
1017      * do not affect whatever pixels are already there.
1018      * <p>
1019      * This method returns immediately in all cases, even if the
1020      * image area to be drawn has not yet been scaled, dithered, and converted
1021      * for the current output device.
1022      * If the current output representation is not yet complete then
1023      * <code>drawImage</code> returns <code>false</code>. As more of
1024      * the image becomes available, the process that loads the image notifies
1025      * the specified image observer.
1026      * <p>
1027      * This method always uses the unscaled version of the image
1028      * to render the scaled rectangle and performs the required
1029      * scaling on the fly. It does not use a cached, scaled version
1030      * of the image for this operation. Scaling of the image from source
1031      * to destination is performed such that the first coordinate
1032      * of the source rectangle is mapped to the first coordinate of
1033      * the destination rectangle, and the second source coordinate is
1034      * mapped to the second destination coordinate. The subimage is
1035      * scaled and flipped as needed to preserve those mappings.
1036      * @param       img the specified image to be drawn. This method does
1037      *                  nothing if <code>img</code> is null.
1038      * @param       dx1 the <i>x</i> coordinate of the first corner of the
1039      *                    destination rectangle.
1040      * @param       dy1 the <i>y</i> coordinate of the first corner of the
1041      *                    destination rectangle.
1042      * @param       dx2 the <i>x</i> coordinate of the second corner of the
1043      *                    destination rectangle.
1044      * @param       dy2 the <i>y</i> coordinate of the second corner of the
1045      *                    destination rectangle.
1046      * @param       sx1 the <i>x</i> coordinate of the first corner of the
1047      *                    source rectangle.
1048      * @param       sy1 the <i>y</i> coordinate of the first corner of the
1049      *                    source rectangle.
1050      * @param       sx2 the <i>x</i> coordinate of the second corner of the
1051      *                    source rectangle.
1052      * @param       sy2 the <i>y</i> coordinate of the second corner of the
1053      *                    source rectangle.
1054      * @param       observer object to be notified as more of the image is
1055      *                    scaled and converted.
1056      * @return   <code>false</code> if the image pixels are still changing;
1057      *           <code>true</code> otherwise.
1058      * @see         java.awt.Image
1059      * @see         java.awt.image.ImageObserver
1060      * @see         java.awt.image.ImageObserver#imageUpdate(java.awt.Image, int, int, int, int, int)
1061      * @since       JDK1.1
1062      */
1063     public abstract boolean drawImage(Image img,
1064                                       int dx1, int dy1, int dx2, int dy2,
1065                                       int sx1, int sy1, int sx2, int sy2,
1066                                       ImageObserver observer);
1067 
1068     /**
1069      * Draws as much of the specified area of the specified image as is
1070      * currently available, scaling it on the fly to fit inside the
1071      * specified area of the destination drawable surface.
1072      * <p>
1073      * Transparent pixels are drawn in the specified background color.
1074      * This operation is equivalent to filling a rectangle of the
1075      * width and height of the specified image with the given color and then
1076      * drawing the image on top of it, but possibly more efficient.
1077      * <p>
1078      * This method returns immediately in all cases, even if the
1079      * image area to be drawn has not yet been scaled, dithered, and converted
1080      * for the current output device.
1081      * If the current output representation is not yet complete then
1082      * <code>drawImage</code> returns <code>false</code>. As more of
1083      * the image becomes available, the process that loads the image notifies
1084      * the specified image observer.
1085      * <p>
1086      * This method always uses the unscaled version of the image
1087      * to render the scaled rectangle and performs the required
1088      * scaling on the fly. It does not use a cached, scaled version
1089      * of the image for this operation. Scaling of the image from source
1090      * to destination is performed such that the first coordinate
1091      * of the source rectangle is mapped to the first coordinate of
1092      * the destination rectangle, and the second source coordinate is
1093      * mapped to the second destination coordinate. The subimage is
1094      * scaled and flipped as needed to preserve those mappings.
1095      * @param       img the specified image to be drawn. This method does
1096      *                  nothing if <code>img</code> is null.
1097      * @param       dx1 the <i>x</i> coordinate of the first corner of the
1098      *                    destination rectangle.
1099      * @param       dy1 the <i>y</i> coordinate of the first corner of the
1100      *                    destination rectangle.
1101      * @param       dx2 the <i>x</i> coordinate of the second corner of the
1102      *                    destination rectangle.
1103      * @param       dy2 the <i>y</i> coordinate of the second corner of the
1104      *                    destination rectangle.
1105      * @param       sx1 the <i>x</i> coordinate of the first corner of the
1106      *                    source rectangle.
1107      * @param       sy1 the <i>y</i> coordinate of the first corner of the
1108      *                    source rectangle.
1109      * @param       sx2 the <i>x</i> coordinate of the second corner of the
1110      *                    source rectangle.
1111      * @param       sy2 the <i>y</i> coordinate of the second corner of the
1112      *                    source rectangle.
1113      * @param       bgcolor the background color to paint under the
1114      *                    non-opaque portions of the image.
1115      * @param       observer object to be notified as more of the image is
1116      *                    scaled and converted.
1117      * @return   <code>false</code> if the image pixels are still changing;
1118      *           <code>true</code> otherwise.
1119      * @see         java.awt.Image
1120      * @see         java.awt.image.ImageObserver
1121      * @see         java.awt.image.ImageObserver#imageUpdate(java.awt.Image, int, int, int, int, int)
1122      * @since       JDK1.1
1123      */
1124     public abstract boolean drawImage(Image img,
1125                                       int dx1, int dy1, int dx2, int dy2,
1126                                       int sx1, int sy1, int sx2, int sy2,
1127                                       Color bgcolor,
1128                                       ImageObserver observer);
1129 
1130     /**
1131      * Disposes of this graphics context and releases
1132      * any system resources that it is using.
1133      * A <code>Graphics</code> object cannot be used after
1134      * <code>dispose</code>has been called.
1135      * <p>
1136      * When a Java program runs, a large number of <code>Graphics</code>
1137      * objects can be created within a short time frame.
1138      * Although the finalization process of the garbage collector
1139      * also disposes of the same system resources, it is preferable
1140      * to manually free the associated resources by calling this
1141      * method rather than to rely on a finalization process which
1142      * may not run to completion for a long period of time.
1143      * <p>
1144      * Graphics objects which are provided as arguments to the
1145      * <code>paint</code> and <code>update</code> methods
1146      * of components are automatically released by the system when
1147      * those methods return. For efficiency, programmers should
1148      * call <code>dispose</code> when finished using
1149      * a <code>Graphics</code> object only if it was created
1150      * directly from a component or another <code>Graphics</code> object.
1151      * @see         java.awt.Graphics#finalize
1152      * @see         java.awt.Component#paint
1153      * @see         java.awt.Component#update
1154      * @see         java.awt.Component#getGraphics
1155      * @see         java.awt.Graphics#create
1156      */
1157     public abstract void dispose();
1158 
1159     /**
1160      * Disposes of this graphics context once it is no longer referenced.
1161      * @see #dispose
1162      */
1163     public void finalize() {
1164         dispose();
1165     }
1166 
1167     /**
1168      * Returns a <code>String</code> object representing this
1169      *                        <code>Graphics</code> object's value.
1170      * @return       a string representation of this graphics context.
1171      */
1172     public String toString() {
1173         return getClass().getName() + "[font=" + getFont() + ",color=" + getColor() + "]";
1174     }
1175 
1176     /**
1177      * Returns the bounding rectangle of the current clipping area.
1178      * @return      the bounding rectangle of the current clipping area
1179      *              or <code>null</code> if no clip is set.
1180      * @deprecated As of JDK version 1.1,
1181      * replaced by <code>getClipBounds()</code>.
1182      */
1183     @Deprecated
1184     public Rectangle getClipRect() {
1185         return getClipBounds();
1186     }
1187 
1188     /**
1189      * Returns true if the specified rectangular area might intersect
1190      * the current clipping area.
1191      * The coordinates of the specified rectangular area are in the
1192      * user coordinate space and are relative to the coordinate
1193      * system origin of this graphics context.
1194      * This method may use an algorithm that calculates a result quickly
1195      * but which sometimes might return true even if the specified
1196      * rectangular area does not intersect the clipping area.
1197      * The specific algorithm employed may thus trade off accuracy for
1198      * speed, but it will never return false unless it can guarantee
1199      * that the specified rectangular area does not intersect the
1200      * current clipping area.
1201      * The clipping area used by this method can represent the
1202      * intersection of the user clip as specified through the clip
1203      * methods of this graphics context as well as the clipping
1204      * associated with the device or image bounds and window visibility.
1205      *
1206      * @param x the x coordinate of the rectangle to test against the clip
1207      * @param y the y coordinate of the rectangle to test against the clip
1208      * @param width the width of the rectangle to test against the clip
1209      * @param height the height of the rectangle to test against the clip
1210      * @return <code>true</code> if the specified rectangle intersects
1211      *         the bounds of the current clip; <code>false</code>
1212      *         otherwise.
1213      */
1214     public boolean hitClip(int x, int y, int width, int height) {
1215         // Note, this implementation is not very efficient.
1216         // Subclasses should override this method and calculate
1217         // the results more directly.
1218         Rectangle clipRect = getClipBounds();
1219         if (clipRect == null) {
1220             return true;
1221         }
1222         return clipRect.intersects(x, y, width, height);
1223     }
1224 
1225     /**
1226      * Returns the bounding rectangle of the current clipping area.
1227      * The coordinates in the rectangle are relative to the coordinate
1228      * system origin of this graphics context.  This method differs
1229      * from {@link #getClipBounds() getClipBounds} in that an existing
1230      * rectangle is used instead of allocating a new one.
1231      * This method refers to the user clip, which is independent of the
1232      * clipping associated with device bounds and window visibility.
1233      *  If no clip has previously been set, or if the clip has been
1234      * cleared using <code>setClip(null)</code>, this method returns the
1235      * specified <code>Rectangle</code>.
1236      * @param  r    the rectangle where the current clipping area is
1237      *              copied to.  Any current values in this rectangle are
1238      *              overwritten.
1239      * @return      the bounding rectangle of the current clipping area.
1240      */
1241     public Rectangle getClipBounds(Rectangle r) {
1242         // Note, this implementation is not very efficient.
1243         // Subclasses should override this method and avoid
1244         // the allocation overhead of getClipBounds().
1245         Rectangle clipRect = getClipBounds();
1246         if (clipRect != null) {
1247             r.x = clipRect.x;
1248             r.y = clipRect.y;
1249             r.width = clipRect.width;
1250             r.height = clipRect.height;
1251         } else if (r == null) {
1252             throw new NullPointerException("null rectangle parameter");
1253         }
1254         return r;
1255     }
1256 }