/*
 * Copyright (c) 1995, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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 */
package java.awt;

import java.io.*;
import java.lang.*;
import java.util.*;
import java.awt.image.ImageObserver;
import java.text.AttributedCharacterIterator;

/**
 * The <code>Graphics</code> class is the abstract base class for
 * all graphics contexts that allow an application to draw onto
 * components that are realized on various devices, as well as
 * onto off-screen images.
 * <p>
 * A <code>Graphics</code> object encapsulates state information needed
 * for the basic rendering operations that Java supports. This
 * state information includes the following properties:
 *
 * <ul>
 * <li>The <code>Component</code> object on which to draw.
 * <li>A translation origin for rendering and clipping coordinates.
 * <li>The current clip.
 * <li>The current color.
 * <li>The current font.
 * <li>The current logical pixel operation function (XOR or Paint).
 * <li>The current XOR alternation color
 * (see {@link Graphics#setXORMode}).
 * </ul>
 * <p>
 * Coordinates are infinitely thin and lie between the pixels of the
 * output device.
 * Operations that draw the outline of a figure operate by traversing
 * an infinitely thin path between pixels with a pixel-sized pen that hangs
 * down and to the right of the anchor point on the path.
 * Operations that fill a figure operate by filling the interior
 * of that infinitely thin path.
 * Operations that render horizontal text render the ascending
 * portion of character glyphs entirely above the baseline coordinate.
 * <p>
 * The graphics pen hangs down and to the right from the path it traverses.
 * This has the following implications:
 * <ul>
 * <li>If you draw a figure that covers a given rectangle, that
 * figure occupies one extra row of pixels on the right and bottom edges
 * as compared to filling a figure that is bounded by that same rectangle.
 * <li>If you draw a horizontal line along the same <i>y</i> coordinate as
 * the baseline of a line of text, that line is drawn entirely below
 * the text, except for any descenders.
 * </ul><p>
 * All coordinates that appear as arguments to the methods of this
 * <code>Graphics</code> object are considered relative to the
 * translation origin of this <code>Graphics</code> object prior to
 * the invocation of the method.
 * <p>
 * All rendering operations modify only pixels which lie within the
 * area bounded by the current clip, which is specified by a {@link Shape}
 * in user space and is controlled by the program using the
 * <code>Graphics</code> object. This <i>user clip</i>
 * is transformed into device space and combined with the
 * <i>device clip</i>, which is defined by the visibility of windows and
 * device extents. The combination of the user clip and device clip
 * defines the <i>composite clip</i>, which determines the final clipping
 * region. The user clip cannot be modified by the rendering
 * system to reflect the resulting composite clip. The user clip can only
 * be changed through the <code>setClip</code> or <code>clipRect</code>
 * methods.
 * All drawing or writing is done in the current color,
 * using the current paint mode, and in the current font.
 *
 * @author Sami Shaio
 * @author Arthur van Hoff
 * @see java.awt.Component
 * @see java.awt.Graphics#clipRect(int, int, int, int)
 * @see java.awt.Graphics#setColor(java.awt.Color)
 * @see java.awt.Graphics#setPaintMode()
 * @see java.awt.Graphics#setXORMode(java.awt.Color)
 * @see java.awt.Graphics#setFont(java.awt.Font)
 * @since JDK1.0
 */
public abstract class Graphics {

 /**
 * Constructs a new <code>Graphics</code> object.
 * This constructor is the default constructor for a graphics
 * context.
 * <p>
 * Since <code>Graphics</code> is an abstract class, applications
 * cannot call this constructor directly. Graphics contexts are
 * obtained from other graphics contexts or are created by calling
 * <code>getGraphics</code> on a component.
 * @see java.awt.Graphics#create()
 * @see java.awt.Component#getGraphics
 */
 protected Graphics() {
 }

 /**
 * Creates a new <code>Graphics</code> object that is
 * a copy of this <code>Graphics</code> object.
 * @return a new graphics context that is a copy of
 * this graphics context.
 */
 public abstract Graphics create();

 /**
 * Creates a new <code>Graphics</code> object based on this
 * <code>Graphics</code> object, but with a new translation and clip area.
 * The new <code>Graphics</code> object has its origin
 * translated to the specified point (<i>x</i>,&nbsp;<i>y</i>).
 * Its clip area is determined by the intersection of the original
 * clip area with the specified rectangle. The arguments are all
 * interpreted in the coordinate system of the original
 * <code>Graphics</code> object. The new graphics context is
 * identical to the original, except in two respects:
 *
 * <ul>
 * <li>
 * The new graphics context is translated by (<i>x</i>,&nbsp;<i>y</i>).
 * That is to say, the point (<code>0</code>,&nbsp;<code>0</code>) in the
 * new graphics context is the same as (<i>x</i>,&nbsp;<i>y</i>) in
 * the original graphics context.
 * <li>
 * The new graphics context has an additional clipping rectangle, in
 * addition to whatever (translated) clipping rectangle it inherited
 * from the original graphics context. The origin of the new clipping
 * rectangle is at (<code>0</code>,&nbsp;<code>0</code>), and its size
 * is specified by the <code>width</code> and <code>height</code>
 * arguments.
 * </ul>
 * <p>
 * @param x the <i>x</i> coordinate.
 * @param y the <i>y</i> coordinate.
 * @param width the width of the clipping rectangle.
 * @param height the height of the clipping rectangle.
 * @return a new graphics context.
 * @see java.awt.Graphics#translate
 * @see java.awt.Graphics#clipRect
 */
 public Graphics create(int x, int y, int width, int height) {
 Graphics g = create();
 if (g == null) return null;
 g.translate(x, y);
 g.clipRect(0, 0, width, height);
 return g;
 }

 /**
 * Translates the origin of the graphics context to the point
 * (<i>x</i>,&nbsp;<i>y</i>) in the current coordinate system.
 * Modifies this graphics context so that its new origin corresponds
 * to the point (<i>x</i>,&nbsp;<i>y</i>) in this graphics context's
 * original coordinate system. All coordinates used in subsequent
 * rendering operations on this graphics context will be relative
 * to this new origin.
 * @param x the <i>x</i> coordinate.
 * @param y the <i>y</i> coordinate.
 */
 public abstract void translate(int x, int y);

 /**
 * Gets this graphics context's current color.
 * @return this graphics context's current color.
 * @see java.awt.Color
 * @see java.awt.Graphics#setColor(Color)
 */
 public abstract Color getColor();

 /**
 * Sets this graphics context's current color to the specified
 * color. All subsequent graphics operations using this graphics
 * context use this specified color.
 * @param c the new rendering color.
 * @see java.awt.Color
 * @see java.awt.Graphics#getColor
 */
 public abstract void setColor(Color c);

 /**
 * Sets the paint mode of this graphics context to overwrite the
 * destination with this graphics context's current color.
 * This sets the logical pixel operation function to the paint or
 * overwrite mode. All subsequent rendering operations will
 * overwrite the destination with the current color.
 */
 public abstract void setPaintMode();

 /**
 * Sets the paint mode of this graphics context to alternate between
 * this graphics context's current color and the new specified color.
 * This specifies that logical pixel operations are performed in the
 * XOR mode, which alternates pixels between the current color and
 * a specified XOR color.
 * <p>
 * When drawing operations are performed, pixels which are the
 * current color are changed to the specified color, and vice versa.
 * <p>
 * Pixels that are of colors other than those two colors are changed
 * in an unpredictable but reversible manner; if the same figure is
 * drawn twice, then all pixels are restored to their original values.
 * @param c1 the XOR alternation color
 */
 public abstract void setXORMode(Color c1);

 /**
 * Gets the current font.
 * @return this graphics context's current font.
 * @see java.awt.Font
 * @see java.awt.Graphics#setFont(Font)
 */
 public abstract Font getFont();

 /**
 * Sets this graphics context's font to the specified font.
 * All subsequent text operations using this graphics context
 * use this font. A null argument is silently ignored.
 * @param font the font.
 * @see java.awt.Graphics#getFont
 * @see java.awt.Graphics#drawString(java.lang.String, int, int)
 * @see java.awt.Graphics#drawBytes(byte[], int, int, int, int)
 * @see java.awt.Graphics#drawChars(char[], int, int, int, int)
 */
 public abstract void setFont(Font font);

 /**
 * Gets the font metrics of the current font.
 * @return the font metrics of this graphics
 * context's current font.
 * @see java.awt.Graphics#getFont
 * @see java.awt.FontMetrics
 * @see java.awt.Graphics#getFontMetrics(Font)
 */
 public FontMetrics getFontMetrics() {
 return getFontMetrics(getFont());
 }

 /**
 * Gets the font metrics for the specified font.
 * @return the font metrics for the specified font.
 * @param f the specified font
 * @see java.awt.Graphics#getFont
 * @see java.awt.FontMetrics
 * @see java.awt.Graphics#getFontMetrics()
 */
 public abstract FontMetrics getFontMetrics(Font f);


 /**
 * Returns the bounding rectangle of the current clipping area.
 * This method refers to the user clip, which is independent of the
 * clipping associated with device bounds and window visibility.
 * If no clip has previously been set, or if the clip has been
 * cleared using <code>setClip(null)</code>, this method returns
 * <code>null</code>.
 * The coordinates in the rectangle are relative to the coordinate
 * system origin of this graphics context.
 * @return the bounding rectangle of the current clipping area,
 * or <code>null</code> if no clip is set.
 * @see java.awt.Graphics#getClip
 * @see java.awt.Graphics#clipRect
 * @see java.awt.Graphics#setClip(int, int, int, int)
 * @see java.awt.Graphics#setClip(Shape)
 * @since JDK1.1
 */
 public abstract Rectangle getClipBounds();

 /**
 * Intersects the current clip with the specified rectangle.
 * The resulting clipping area is the intersection of the current
 * clipping area and the specified rectangle. If there is no
 * current clipping area, either because the clip has never been
 * set, or the clip has been cleared using <code>setClip(null)</code>,
 * the specified rectangle becomes the new clip.
 * This method sets the user clip, which is independent of the
 * clipping associated with device bounds and window visibility.
 * This method can only be used to make the current clip smaller.
 * To set the current clip larger, use any of the setClip methods.
 * Rendering operations have no effect outside of the clipping area.
 * @param x the x coordinate of the rectangle to intersect the clip with
 * @param y the y coordinate of the rectangle to intersect the clip with
 * @param width the width of the rectangle to intersect the clip with
 * @param height the height of the rectangle to intersect the clip with
 * @see #setClip(int, int, int, int)
 * @see #setClip(Shape)
 */
 public abstract void clipRect(int x, int y, int width, int height);

 /**
 * Sets the current clip to the rectangle specified by the given
 * coordinates. This method sets the user clip, which is
 * independent of the clipping associated with device bounds
 * and window visibility.
 * Rendering operations have no effect outside of the clipping area.
 * @param x the <i>x</i> coordinate of the new clip rectangle.
 * @param y the <i>y</i> coordinate of the new clip rectangle.
 * @param width the width of the new clip rectangle.
 * @param height the height of the new clip rectangle.
 * @see java.awt.Graphics#clipRect
 * @see java.awt.Graphics#setClip(Shape)
 * @see java.awt.Graphics#getClip
 * @since JDK1.1
 */
 public abstract void setClip(int x, int y, int width, int height);

 /**
 * Gets the current clipping area.
 * This method returns the user clip, which is independent of the
 * clipping associated with device bounds and window visibility.
 * If no clip has previously been set, or if the clip has been
 * cleared using <code>setClip(null)</code>, this method returns
 * <code>null</code>.
 * @return a <code>Shape</code> object representing the
 * current clipping area, or <code>null</code> if
 * no clip is set.
 * @see java.awt.Graphics#getClipBounds
 * @see java.awt.Graphics#clipRect
 * @see java.awt.Graphics#setClip(int, int, int, int)
 * @see java.awt.Graphics#setClip(Shape)
 * @since JDK1.1
 */
 public abstract Shape getClip();

 /**
 * Sets the current clipping area to an arbitrary clip shape.
 * Not all objects that implement the <code>Shape</code>
 * interface can be used to set the clip. The only
 * <code>Shape</code> objects that are guaranteed to be
 * supported are <code>Shape</code> objects that are
 * obtained via the <code>getClip</code> method and via
 * <code>Rectangle</code> objects. This method sets the
 * user clip, which is independent of the clipping associated
 * with device bounds and window visibility.
 * @param clip the <code>Shape</code> to use to set the clip
 * @see java.awt.Graphics#getClip()
 * @see java.awt.Graphics#clipRect
 * @see java.awt.Graphics#setClip(int, int, int, int)
 * @since JDK1.1
 */
 public abstract void setClip(Shape clip);

 /**
 * Copies an area of the component by a distance specified by
 * <code>dx</code> and <code>dy</code>. From the point specified
 * by <code>x</code> and <code>y</code>, this method
 * copies downwards and to the right. To copy an area of the
 * component to the left or upwards, specify a negative value for
 * <code>dx</code> or <code>dy</code>.
 * If a portion of the source rectangle lies outside the bounds
 * of the component, or is obscured by another window or component,
 * <code>copyArea</code> will be unable to copy the associated
 * pixels. The area that is omitted can be refreshed by calling
 * the component's <code>paint</code> method.
 * @param x the <i>x</i> coordinate of the source rectangle.
 * @param y the <i>y</i> coordinate of the source rectangle.
 * @param width the width of the source rectangle.
 * @param height the height of the source rectangle.
 * @param dx the horizontal distance to copy the pixels.
 * @param dy the vertical distance to copy the pixels.
 */
 public abstract void copyArea(int x, int y, int width, int height,
 int dx, int dy);

 /**
 * Draws a line, using the current color, between the points
 * <code>(x1,&nbsp;y1)</code> and <code>(x2,&nbsp;y2)</code>
 * in this graphics context's coordinate system.
 * @param x1 the first point's <i>x</i> coordinate.
 * @param y1 the first point's <i>y</i> coordinate.
 * @param x2 the second point's <i>x</i> coordinate.
 * @param y2 the second point's <i>y</i> coordinate.
 */
 public abstract void drawLine(int x1, int y1, int x2, int y2);

 /**
 * Fills the specified rectangle.
 * The left and right edges of the rectangle are at
 * <code>x</code> and <code>x&nbsp;+&nbsp;width&nbsp;-&nbsp;1</code>.
 * The top and bottom edges are at
 * <code>y</code> and <code>y&nbsp;+&nbsp;height&nbsp;-&nbsp;1</code>.
 * The resulting rectangle covers an area
 * <code>width</code> pixels wide by
 * <code>height</code> pixels tall.
 * The rectangle is filled using the graphics context's current color.
 * @param x the <i>x</i> coordinate
 * of the rectangle to be filled.
 * @param y the <i>y</i> coordinate
 * of the rectangle to be filled.
 * @param width the width of the rectangle to be filled.
 * @param height the height of the rectangle to be filled.
 * @see java.awt.Graphics#clearRect
 * @see java.awt.Graphics#drawRect
 */
 public abstract void fillRect(int x, int y, int width, int height);

 /**
 * Draws the outline of the specified rectangle.
 * The left and right edges of the rectangle are at
 * <code>x</code> and <code>x&nbsp;+&nbsp;width</code>.
 * The top and bottom edges are at
 * <code>y</code> and <code>y&nbsp;+&nbsp;height</code>.
 * The rectangle is drawn using the graphics context's current color.
 * @param x the <i>x</i> coordinate
 * of the rectangle to be drawn.
 * @param y the <i>y</i> coordinate
 * of the rectangle to be drawn.
 * @param width the width of the rectangle to be drawn.
 * @param height the height of the rectangle to be drawn.
 * @see java.awt.Graphics#fillRect
 * @see java.awt.Graphics#clearRect
 */
 public void drawRect(int x, int y, int width, int height) {
 if ((width < 0) || (height < 0)) {
 return;
 }

 if (height == 0 || width == 0) {
 drawLine(x, y, x + width, y + height);
 } else {
 drawLine(x, y, x + width - 1, y);
 drawLine(x + width, y, x + width, y + height - 1);
 drawLine(x + width, y + height, x + 1, y + height);
 drawLine(x, y + height, x, y + 1);
 }
 }

 /**
 * Clears the specified rectangle by filling it with the background
 * color of the current drawing surface. This operation does not
 * use the current paint mode.
 * <p>
 * Beginning with Java&nbsp;1.1, the background color
 * of offscreen images may be system dependent. Applications should
 * use <code>setColor</code> followed by <code>fillRect</code> to
 * ensure that an offscreen image is cleared to a specific color.
 * @param x the <i>x</i> coordinate of the rectangle to clear.
 * @param y the <i>y</i> coordinate of the rectangle to clear.
 * @param width the width of the rectangle to clear.
 * @param height the height of the rectangle to clear.
 * @see java.awt.Graphics#fillRect(int, int, int, int)
 * @see java.awt.Graphics#drawRect
 * @see java.awt.Graphics#setColor(java.awt.Color)
 * @see java.awt.Graphics#setPaintMode
 * @see java.awt.Graphics#setXORMode(java.awt.Color)
 */
 public abstract void clearRect(int x, int y, int width, int height);

 /**
 * Draws an outlined round-cornered rectangle using this graphics
 * context's current color. The left and right edges of the rectangle
 * are at <code>x</code> and <code>x&nbsp;+&nbsp;width</code>,
 * respectively. The top and bottom edges of the rectangle are at
 * <code>y</code> and <code>y&nbsp;+&nbsp;height</code>.
 * @param x the <i>x</i> coordinate of the rectangle to be drawn.
 * @param y the <i>y</i> coordinate of the rectangle to be drawn.
 * @param width the width of the rectangle to be drawn.
 * @param height the height of the rectangle to be drawn.
 * @param arcWidth the horizontal diameter of the arc
 * at the four corners.
 * @param arcHeight the vertical diameter of the arc
 * at the four corners.
 * @see java.awt.Graphics#fillRoundRect
 */
 public abstract void drawRoundRect(int x, int y, int width, int height,
 int arcWidth, int arcHeight);

 /**
 * Fills the specified rounded corner rectangle with the current color.
 * The left and right edges of the rectangle
 * are at <code>x</code> and <code>x&nbsp;+&nbsp;width&nbsp;-&nbsp;1</code>,
 * respectively. The top and bottom edges of the rectangle are at
 * <code>y</code> and <code>y&nbsp;+&nbsp;height&nbsp;-&nbsp;1</code>.
 * @param x the <i>x</i> coordinate of the rectangle to be filled.
 * @param y the <i>y</i> coordinate of the rectangle to be filled.
 * @param width the width of the rectangle to be filled.
 * @param height the height of the rectangle to be filled.
 * @param arcWidth the horizontal diameter
 * of the arc at the four corners.
 * @param arcHeight the vertical diameter
 * of the arc at the four corners.
 * @see java.awt.Graphics#drawRoundRect
 */
 public abstract void fillRoundRect(int x, int y, int width, int height,
 int arcWidth, int arcHeight);

 /**
 * Draws a 3-D highlighted outline of the specified rectangle.
 * The edges of the rectangle are highlighted so that they
 * appear to be beveled and lit from the upper left corner.
 * <p>
 * The colors used for the highlighting effect are determined
 * based on the current color.
 * The resulting rectangle covers an area that is
 * <code>width&nbsp;+&nbsp;1</code> pixels wide
 * by <code>height&nbsp;+&nbsp;1</code> pixels tall.
 * @param x the <i>x</i> coordinate of the rectangle to be drawn.
 * @param y the <i>y</i> coordinate of the rectangle to be drawn.
 * @param width the width of the rectangle to be drawn.
 * @param height the height of the rectangle to be drawn.
 * @param raised a boolean that determines whether the rectangle
 * appears to be raised above the surface
 * or sunk into the surface.
 * @see java.awt.Graphics#fill3DRect
 */
 public void draw3DRect(int x, int y, int width, int height,
 boolean raised) {
 Color c = getColor();
 Color brighter = c.brighter();
 Color darker = c.darker();

 setColor(raised ? brighter : darker);
 drawLine(x, y, x, y + height);
 drawLine(x + 1, y, x + width - 1, y);
 setColor(raised ? darker : brighter);
 drawLine(x + 1, y + height, x + width, y + height);
 drawLine(x + width, y, x + width, y + height - 1);
 setColor(c);
 }

 /**
 * Paints a 3-D highlighted rectangle filled with the current color.
 * The edges of the rectangle will be highlighted so that it appears
 * as if the edges were beveled and lit from the upper left corner.
 * The colors used for the highlighting effect will be determined from
 * the current color.
 * @param x the <i>x</i> coordinate of the rectangle to be filled.
 * @param y the <i>y</i> coordinate of the rectangle to be filled.
 * @param width the width of the rectangle to be filled.
 * @param height the height of the rectangle to be filled.
 * @param raised a boolean value that determines whether the
 * rectangle appears to be raised above the surface
 * or etched into the surface.
 * @see java.awt.Graphics#draw3DRect
 */
 public void fill3DRect(int x, int y, int width, int height,
 boolean raised) {
 Color c = getColor();
 Color brighter = c.brighter();
 Color darker = c.darker();

 if (!raised) {
 setColor(darker);
 }
 fillRect(x+1, y+1, width-2, height-2);
 setColor(raised ? brighter : darker);
 drawLine(x, y, x, y + height - 1);
 drawLine(x + 1, y, x + width - 2, y);
 setColor(raised ? darker : brighter);
 drawLine(x + 1, y + height - 1, x + width - 1, y + height - 1);
 drawLine(x + width - 1, y, x + width - 1, y + height - 2);
 setColor(c);
 }

 /**
 * Draws the outline of an oval.
 * The result is a circle or ellipse that fits within the
 * rectangle specified by the <code>x</code>, <code>y</code>,
 * <code>width</code>, and <code>height</code> arguments.
 * <p>
 * The oval covers an area that is
 * <code>width&nbsp;+&nbsp;1</code> pixels wide
 * and <code>height&nbsp;+&nbsp;1</code> pixels tall.
 * @param x the <i>x</i> coordinate of the upper left
 * corner of the oval to be drawn.
 * @param y the <i>y</i> coordinate of the upper left
 * corner of the oval to be drawn.
 * @param width the width of the oval to be drawn.
 * @param height the height of the oval to be drawn.
 * @see java.awt.Graphics#fillOval
 */
 public abstract void drawOval(int x, int y, int width, int height);

 /**
 * Fills an oval bounded by the specified rectangle with the
 * current color.
 * @param x the <i>x</i> coordinate of the upper left corner
 * of the oval to be filled.
 * @param y the <i>y</i> coordinate of the upper left corner
 * of the oval to be filled.
 * @param width the width of the oval to be filled.
 * @param height the height of the oval to be filled.
 * @see java.awt.Graphics#drawOval
 */
 public abstract void fillOval(int x, int y, int width, int height);

 /**
 * Draws the outline of a circular or elliptical arc
 * covering the specified rectangle.
 * <p>
 * The resulting arc begins at <code>startAngle</code> and extends
 * for <code>arcAngle</code> degrees, using the current color.
 * Angles are interpreted such that 0&nbsp;degrees
 * is at the 3&nbsp;o'clock position.
 * A positive value indicates a counter-clockwise rotation
 * while a negative value indicates a clockwise rotation.
 * <p>
 * The center of the arc is the center of the rectangle whose origin
 * is (<i>x</i>,&nbsp;<i>y</i>) and whose size is specified by the
 * <code>width</code> and <code>height</code> arguments.
 * <p>
 * The resulting arc covers an area
 * <code>width&nbsp;+&nbsp;1</code> pixels wide
 * by <code>height&nbsp;+&nbsp;1</code> pixels tall.
 * <p>
 * The angles are specified relative to the non-square extents of
 * the bounding rectangle such that 45 degrees always falls on the
 * line from the center of the ellipse to the upper right corner of
 * the bounding rectangle. As a result, if the bounding rectangle is
 * noticeably longer in one axis than the other, the angles to the
 * start and end of the arc segment will be skewed farther along the
 * longer axis of the bounds.
 * @param x the <i>x</i> coordinate of the
 * upper-left corner of the arc to be drawn.
 * @param y the <i>y</i> coordinate of the
 * upper-left corner of the arc to be drawn.
 * @param width the width of the arc to be drawn.
 * @param height the height of the arc to be drawn.
 * @param startAngle the beginning angle.
 * @param arcAngle the angular extent of the arc,
 * relative to the start angle.
 * @see java.awt.Graphics#fillArc
 */
 public abstract void drawArc(int x, int y, int width, int height,
 int startAngle, int arcAngle);

 /**
 * Fills a circular or elliptical arc covering the specified rectangle.
 * <p>
 * The resulting arc begins at <code>startAngle</code> and extends
 * for <code>arcAngle</code> degrees.
 * Angles are interpreted such that 0&nbsp;degrees
 * is at the 3&nbsp;o'clock position.
 * A positive value indicates a counter-clockwise rotation
 * while a negative value indicates a clockwise rotation.
 * <p>
 * The center of the arc is the center of the rectangle whose origin
 * is (<i>x</i>,&nbsp;<i>y</i>) and whose size is specified by the
 * <code>width</code> and <code>height</code> arguments.
 * <p>
 * The resulting arc covers an area
 * <code>width&nbsp;+&nbsp;1</code> pixels wide
 * by <code>height&nbsp;+&nbsp;1</code> pixels tall.
 * <p>
 * The angles are specified relative to the non-square extents of
 * the bounding rectangle such that 45 degrees always falls on the
 * line from the center of the ellipse to the upper right corner of
 * the bounding rectangle. As a result, if the bounding rectangle is
 * noticeably longer in one axis than the other, the angles to the
 * start and end of the arc segment will be skewed farther along the
 * longer axis of the bounds.
 * @param x the <i>x</i> coordinate of the
 * upper-left corner of the arc to be filled.
 * @param y the <i>y</i> coordinate of the
 * upper-left corner of the arc to be filled.
 * @param width the width of the arc to be filled.
 * @param height the height of the arc to be filled.
 * @param startAngle the beginning angle.
 * @param arcAngle the angular extent of the arc,
 * relative to the start angle.
 * @see java.awt.Graphics#drawArc
 */
 public abstract void fillArc(int x, int y, int width, int height,
 int startAngle, int arcAngle);

 /**
 * Draws a sequence of connected lines defined by
 * arrays of <i>x</i> and <i>y</i> coordinates.
 * Each pair of (<i>x</i>,&nbsp;<i>y</i>) coordinates defines a point.
 * The figure is not closed if the first point
 * differs from the last point.
 * @param xPoints an array of <i>x</i> points
 * @param yPoints an array of <i>y</i> points
 * @param nPoints the total number of points
 * @see java.awt.Graphics#drawPolygon(int[], int[], int)
 * @since JDK1.1
 */
 public abstract void drawPolyline(int xPoints[], int yPoints[],
 int nPoints);

 /**
 * Draws a closed polygon defined by
 * arrays of <i>x</i> and <i>y</i> coordinates.
 * Each pair of (<i>x</i>,&nbsp;<i>y</i>) coordinates defines a point.
 * <p>
 * This method draws the polygon defined by <code>nPoint</code> line
 * segments, where the first <code>nPoint&nbsp;-&nbsp;1</code>
 * line segments are line segments from
 * <code>(xPoints[i&nbsp;-&nbsp;1],&nbsp;yPoints[i&nbsp;-&nbsp;1])</code>
 * to <code>(xPoints[i],&nbsp;yPoints[i])</code>, for
 * 1&nbsp;&le;&nbsp;<i>i</i>&nbsp;&le;&nbsp;<code>nPoints</code>.
 * The figure is automatically closed by drawing a line connecting
 * the final point to the first point, if those points are different.
 * @param xPoints a an array of <code>x</code> coordinates.
 * @param yPoints a an array of <code>y</code> coordinates.
 * @param nPoints a the total number of points.
 * @see java.awt.Graphics#fillPolygon
 * @see java.awt.Graphics#drawPolyline
 */
 public abstract void drawPolygon(int xPoints[], int yPoints[],
 int nPoints);

 /**
 * Draws the outline of a polygon defined by the specified
 * <code>Polygon</code> object.
 * @param p the polygon to draw.
 * @see java.awt.Graphics#fillPolygon
 * @see java.awt.Graphics#drawPolyline
 */
 public void drawPolygon(Polygon p) {
 drawPolygon(p.xpoints, p.ypoints, p.npoints);
 }

 /**
 * Fills a closed polygon defined by
 * arrays of <i>x</i> and <i>y</i> coordinates.
 * <p>
 * This method draws the polygon defined by <code>nPoint</code> line
 * segments, where the first <code>nPoint&nbsp;-&nbsp;1</code>
 * line segments are line segments from
 * <code>(xPoints[i&nbsp;-&nbsp;1],&nbsp;yPoints[i&nbsp;-&nbsp;1])</code>
 * to <code>(xPoints[i],&nbsp;yPoints[i])</code>, for
 * 1&nbsp;&le;&nbsp;<i>i</i>&nbsp;&le;&nbsp;<code>nPoints</code>.
 * The figure is automatically closed by drawing a line connecting
 * the final point to the first point, if those points are different.
 * <p>
 * The area inside the polygon is defined using an
 * even-odd fill rule, also known as the alternating rule.
 * @param xPoints a an array of <code>x</code> coordinates.
 * @param yPoints a an array of <code>y</code> coordinates.
 * @param nPoints a the total number of points.
 * @see java.awt.Graphics#drawPolygon(int[], int[], int)
 */
 public abstract void fillPolygon(int xPoints[], int yPoints[],
 int nPoints);

 /**
 * Fills the polygon defined by the specified Polygon object with
 * the graphics context's current color.
 * <p>
 * The area inside the polygon is defined using an
 * even-odd fill rule, also known as the alternating rule.
 * @param p the polygon to fill.
 * @see java.awt.Graphics#drawPolygon(int[], int[], int)
 */
 public void fillPolygon(Polygon p) {
 fillPolygon(p.xpoints, p.ypoints, p.npoints);
 }

 /**
 * Draws the text given by the specified string, using this
 * graphics context's current font and color. The baseline of the
 * leftmost character is at position (<i>x</i>,&nbsp;<i>y</i>) in this
 * graphics context's coordinate system.
 * @param str the string to be drawn.
 * @param x the <i>x</i> coordinate.
 * @param y the <i>y</i> coordinate.
 * @throws NullPointerException if <code>str</code> is <code>null</code>.
 * @see java.awt.Graphics#drawBytes
 * @see java.awt.Graphics#drawChars
 */
 public abstract void drawString(String str, int x, int y);

 /**
 * Renders the text of the specified iterator applying its attributes
 * in accordance with the specification of the
 * {@link java.awt.font.TextAttribute TextAttribute} class.
 * <p>
 * The baseline of the leftmost character is at position
 * (<i>x</i>,&nbsp;<i>y</i>) in this graphics context's coordinate system.
 * @param iterator the iterator whose text is to be drawn
 * @param x the <i>x</i> coordinate.
 * @param y the <i>y</i> coordinate.
 * @throws NullPointerException if <code>iterator</code> is
 * <code>null</code>.
 * @see java.awt.Graphics#drawBytes
 * @see java.awt.Graphics#drawChars
 */
 public abstract void drawString(AttributedCharacterIterator iterator,
 int x, int y);

 /**
 * Draws the text given by the specified character array, using this
 * graphics context's current font and color. The baseline of the
 * first character is at position (<i>x</i>,&nbsp;<i>y</i>) in this
 * graphics context's coordinate system.
 * @param data the array of characters to be drawn
 * @param offset the start offset in the data
 * @param length the number of characters to be drawn
 * @param x the <i>x</i> coordinate of the baseline of the text
 * @param y the <i>y</i> coordinate of the baseline of the text
 * @throws NullPointerException if <code>data</code> is <code>null</code>.
 * @throws IndexOutOfBoundsException if <code>offset</code> or
 * <code>length</code>is less than zero, or
 * <code>offset+length</code> is greater than the length of the
 * <code>data</code> array.
 * @see java.awt.Graphics#drawBytes
 * @see java.awt.Graphics#drawString
 */
 public void drawChars(char data[], int offset, int length, int x, int y) {
 drawString(new String(data, offset, length), x, y);
 }

 /**
 * Draws the text given by the specified byte array, using this
 * graphics context's current font and color. The baseline of the
 * first character is at position (<i>x</i>,&nbsp;<i>y</i>) in this
 * graphics context's coordinate system.
 * <p>
 * Use of this method is not recommended as each byte is interpreted
 * as a Unicode code point in the range 0 to 255, and so can only be
 * used to draw Latin characters in that range.
 * @param data the data to be drawn
 * @param offset the start offset in the data
 * @param length the number of bytes that are drawn
 * @param x the <i>x</i> coordinate of the baseline of the text
 * @param y the <i>y</i> coordinate of the baseline of the text
 * @throws NullPointerException if <code>data</code> is <code>null</code>.
 * @throws IndexOutOfBoundsException if <code>offset</code> or
 * <code>length</code>is less than zero, or <code>offset+length</code>
 * is greater than the length of the <code>data</code> array.
 * @see java.awt.Graphics#drawChars
 * @see java.awt.Graphics#drawString
 */
 public void drawBytes(byte data[], int offset, int length, int x, int y) {
 drawString(new String(data, 0, offset, length), x, y);
 }

 /**
 * Draws as much of the specified image as is currently available.
 * The image is drawn with its top-left corner at
 * (<i>x</i>,&nbsp;<i>y</i>) in this graphics context's coordinate
 * space. Transparent pixels in the image do not affect whatever
 * pixels are already there.
 * <p>
 * This method returns immediately in all cases, even if the
 * complete image has not yet been loaded, and it has not been dithered
 * and converted for the current output device.
 * <p>
 * If the image has completely loaded and its pixels are
 * no longer being changed, then
 * <code>drawImage</code> returns <code>true</code>.
 * Otherwise, <code>drawImage</code> returns <code>false</code>
 * and as more of
 * the image becomes available
 * or it is time to draw another frame of animation,
 * the process that loads the image notifies
 * the specified image observer.
 * @param img the specified image to be drawn. This method does
 * nothing if <code>img</code> is null.
 * @param x the <i>x</i> coordinate.
 * @param y the <i>y</i> coordinate.
 * @param observer object to be notified as more of
 * the image is converted.
 * @return <code>false</code> if the image pixels are still changing;
 * <code>true</code> otherwise.
 * @see java.awt.Image
 * @see java.awt.image.ImageObserver
 * @see java.awt.image.ImageObserver#imageUpdate(java.awt.Image, int, int, int, int, int)
 */
 public abstract boolean drawImage(Image img, int x, int y,
 ImageObserver observer);

 /**
 * Draws as much of the specified image as has already been scaled
 * to fit inside the specified rectangle.
 * <p>
 * The image is drawn inside the specified rectangle of this
 * graphics context's coordinate space, and is scaled if
 * necessary. Transparent pixels do not affect whatever pixels
 * are already there.
 * <p>
 * This method returns immediately in all cases, even if the
 * entire image has not yet been scaled, dithered, and converted
 * for the current output device.
 * If the current output representation is not yet complete, then
 * <code>drawImage</code> returns <code>false</code>. As more of
 * the image becomes available, the process that loads the image notifies
 * the image observer by calling its <code>imageUpdate</code> method.
 * <p>
 * A scaled version of an image will not necessarily be
 * available immediately just because an unscaled version of the
 * image has been constructed for this output device. Each size of
 * the image may be cached separately and generated from the original
 * data in a separate image production sequence.
 * @param img the specified image to be drawn. This method does
 * nothing if <code>img</code> is null.
 * @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.
 * @param observer object to be notified as more of
 * the image is converted.
 * @return <code>false</code> if the image pixels are still changing;
 * <code>true</code> otherwise.
 * @see java.awt.Image
 * @see java.awt.image.ImageObserver
 * @see java.awt.image.ImageObserver#imageUpdate(java.awt.Image, int, int, int, int, int)
 */
 public abstract boolean drawImage(Image img, int x, int y,
 int width, int height,
 ImageObserver observer);

 /**
 * Draws as much of the specified image as is currently available.
 * The image is drawn with its top-left corner at
 * (<i>x</i>,&nbsp;<i>y</i>) in this graphics context's coordinate
 * space. Transparent pixels are drawn in the specified
 * background color.
 * <p>
 * This operation is equivalent to filling a rectangle of the
 * width and height of the specified image with the given color and then
 * drawing the image on top of it, but possibly more efficient.
 * <p>
 * This method returns immediately in all cases, even if the
 * complete image has not yet been loaded, and it has not been dithered
 * and converted for the current output device.
 * <p>
 * If the image has completely loaded and its pixels are
 * no longer being changed, then
 * <code>drawImage</code> returns <code>true</code>.
 * Otherwise, <code>drawImage</code> returns <code>false</code>
 * and as more of
 * the image becomes available
 * or it is time to draw another frame of animation,
 * the process that loads the image notifies
 * the specified image observer.
 * @param img the specified image to be drawn. This method does
 * nothing if <code>img</code> is null.
 * @param x the <i>x</i> coordinate.
 * @param y the <i>y</i> coordinate.
 * @param bgcolor the background color to paint under the
 * non-opaque portions of the image.
 * @param observer object to be notified as more of
 * the image is converted.
 * @return <code>false</code> if the image pixels are still changing;
 * <code>true</code> otherwise.
 * @see java.awt.Image
 * @see java.awt.image.ImageObserver
 * @see java.awt.image.ImageObserver#imageUpdate(java.awt.Image, int, int, int, int, int)
 */
 public abstract boolean drawImage(Image img, int x, int y,
 Color bgcolor,
 ImageObserver observer);

 /**
 * Draws as much of the specified image as has already been scaled
 * to fit inside the specified rectangle.
 * <p>
 * The image is drawn inside the specified rectangle of this
 * graphics context's coordinate space, and is scaled if
 * necessary. Transparent pixels are drawn in the specified
 * background color.
 * This operation is equivalent to filling a rectangle of the
 * width and height of the specified image with the given color and then
 * drawing the image on top of it, but possibly more efficient.
 * <p>
 * This method returns immediately in all cases, even if the
 * entire image has not yet been scaled, dithered, and converted
 * for the current output device.
 * If the current output representation is not yet complete then
 * <code>drawImage</code> returns <code>false</code>. As more of
 * the image becomes available, the process that loads the image notifies
 * the specified image observer.
 * <p>
 * A scaled version of an image will not necessarily be
 * available immediately just because an unscaled version of the
 * image has been constructed for this output device. Each size of
 * the image may be cached separately and generated from the original
 * data in a separate image production sequence.
 * @param img the specified image to be drawn. This method does
 * nothing if <code>img</code> is null.
 * @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.
 * @param bgcolor the background color to paint under the
 * non-opaque portions of the image.
 * @param observer object to be notified as more of
 * the image is converted.
 * @return <code>false</code> if the image pixels are still changing;
 * <code>true</code> otherwise.
 * @see java.awt.Image
 * @see java.awt.image.ImageObserver
 * @see java.awt.image.ImageObserver#imageUpdate(java.awt.Image, int, int, int, int, int)
 */
 public abstract boolean drawImage(Image img, int x, int y,
 int width, int height,
 Color bgcolor,
 ImageObserver observer);

 /**
 * Draws as much of the specified area of the specified image as is
 * currently available, scaling it on the fly to fit inside the
 * specified area of the destination drawable surface. Transparent pixels
 * do not affect whatever pixels are already there.
 * <p>
 * This method returns immediately in all cases, even if the
 * image area to be drawn has not yet been scaled, dithered, and converted
 * for the current output device.
 * If the current output representation is not yet complete then
 * <code>drawImage</code> returns <code>false</code>. As more of
 * the image becomes available, the process that loads the image notifies
 * the specified image observer.
 * <p>
 * This method always uses the unscaled version of the image
 * to render the scaled rectangle and performs the required
 * scaling on the fly. It does not use a cached, scaled version
 * of the image for this operation. Scaling of the image from source
 * to destination is performed such that the first coordinate
 * of the source rectangle is mapped to the first coordinate of
 * the destination rectangle, and the second source coordinate is
 * mapped to the second destination coordinate. The subimage is
 * scaled and flipped as needed to preserve those mappings.
 * @param img the specified image to be drawn. This method does
 * nothing if <code>img</code> is null.
 * @param dx1 the <i>x</i> coordinate of the first corner of the
 * destination rectangle.
 * @param dy1 the <i>y</i> coordinate of the first corner of the
 * destination rectangle.
 * @param dx2 the <i>x</i> coordinate of the second corner of the
 * destination rectangle.
 * @param dy2 the <i>y</i> coordinate of the second corner of the
 * destination rectangle.
 * @param sx1 the <i>x</i> coordinate of the first corner of the
 * source rectangle.
 * @param sy1 the <i>y</i> coordinate of the first corner of the
 * source rectangle.
 * @param sx2 the <i>x</i> coordinate of the second corner of the
 * source rectangle.
 * @param sy2 the <i>y</i> coordinate of the second corner of the
 * source rectangle.
 * @param observer object to be notified as more of the image is
 * scaled and converted.
 * @return <code>false</code> if the image pixels are still changing;
 * <code>true</code> otherwise.
 * @see java.awt.Image
 * @see java.awt.image.ImageObserver
 * @see java.awt.image.ImageObserver#imageUpdate(java.awt.Image, int, int, int, int, int)
 * @since JDK1.1
 */
 public abstract boolean drawImage(Image img,
 int dx1, int dy1, int dx2, int dy2,
 int sx1, int sy1, int sx2, int sy2,
 ImageObserver observer);

 /**
 * Draws as much of the specified area of the specified image as is
 * currently available, scaling it on the fly to fit inside the
 * specified area of the destination drawable surface.
 * <p>
 * Transparent pixels are drawn in the specified background color.
 * This operation is equivalent to filling a rectangle of the
 * width and height of the specified image with the given color and then
 * drawing the image on top of it, but possibly more efficient.
 * <p>
 * This method returns immediately in all cases, even if the
 * image area to be drawn has not yet been scaled, dithered, and converted
 * for the current output device.
 * If the current output representation is not yet complete then
 * <code>drawImage</code> returns <code>false</code>. As more of
 * the image becomes available, the process that loads the image notifies
 * the specified image observer.
 * <p>
 * This method always uses the unscaled version of the image
 * to render the scaled rectangle and performs the required
 * scaling on the fly. It does not use a cached, scaled version
 * of the image for this operation. Scaling of the image from source
 * to destination is performed such that the first coordinate
 * of the source rectangle is mapped to the first coordinate of
 * the destination rectangle, and the second source coordinate is
 * mapped to the second destination coordinate. The subimage is
 * scaled and flipped as needed to preserve those mappings.
 * @param img the specified image to be drawn. This method does
 * nothing if <code>img</code> is null.
 * @param dx1 the <i>x</i> coordinate of the first corner of the
 * destination rectangle.
 * @param dy1 the <i>y</i> coordinate of the first corner of the
 * destination rectangle.
 * @param dx2 the <i>x</i> coordinate of the second corner of the
 * destination rectangle.
 * @param dy2 the <i>y</i> coordinate of the second corner of the
 * destination rectangle.
 * @param sx1 the <i>x</i> coordinate of the first corner of the
 * source rectangle.
 * @param sy1 the <i>y</i> coordinate of the first corner of the
 * source rectangle.
 * @param sx2 the <i>x</i> coordinate of the second corner of the
 * source rectangle.
 * @param sy2 the <i>y</i> coordinate of the second corner of the
 * source rectangle.
 * @param bgcolor the background color to paint under the
 * non-opaque portions of the image.
 * @param observer object to be notified as more of the image is
 * scaled and converted.
 * @return <code>false</code> if the image pixels are still changing;
 * <code>true</code> otherwise.
 * @see java.awt.Image
 * @see java.awt.image.ImageObserver
 * @see java.awt.image.ImageObserver#imageUpdate(java.awt.Image, int, int, int, int, int)
 * @since JDK1.1
 */
 public abstract boolean drawImage(Image img,
 int dx1, int dy1, int dx2, int dy2,
 int sx1, int sy1, int sx2, int sy2,
 Color bgcolor,
 ImageObserver observer);

 /**
 * Disposes of this graphics context and releases
 * any system resources that it is using.
 * A <code>Graphics</code> object cannot be used after
 * <code>dispose</code>has been called.
 * <p>
 * When a Java program runs, a large number of <code>Graphics</code>
 * objects can be created within a short time frame.
 * Although the finalization process of the garbage collector
 * also disposes of the same system resources, it is preferable
 * to manually free the associated resources by calling this
 * method rather than to rely on a finalization process which
 * may not run to completion for a long period of time.
 * <p>
 * Graphics objects which are provided as arguments to the
 * <code>paint</code> and <code>update</code> methods
 * of components are automatically released by the system when
 * those methods return. For efficiency, programmers should
 * call <code>dispose</code> when finished using
 * a <code>Graphics</code> object only if it was created
 * directly from a component or another <code>Graphics</code> object.
 * @see java.awt.Graphics#finalize
 * @see java.awt.Component#paint
 * @see java.awt.Component#update
 * @see java.awt.Component#getGraphics
 * @see java.awt.Graphics#create
 */
 public abstract void dispose();

 /**
 * Disposes of this graphics context once it is no longer referenced.
 * @see #dispose
 */
 public void finalize() {
 dispose();
 }

 /**
 * Returns a <code>String</code> object representing this
 * <code>Graphics</code> object's value.
 * @return a string representation of this graphics context.
 */
 public String toString() {
 return getClass().getName() + "[font=" + getFont() + ",color=" + getColor() + "]";
 }

 /**
 * Returns the bounding rectangle of the current clipping area.
 * @return the bounding rectangle of the current clipping area
 * or <code>null</code> if no clip is set.
 * @deprecated As of JDK version 1.1,
 * replaced by <code>getClipBounds()</code>.
 */
 @Deprecated
 public Rectangle getClipRect() {
 return getClipBounds();
 }

 /**
 * Returns true if the specified rectangular area might intersect
 * the current clipping area.
 * The coordinates of the specified rectangular area are in the
 * user coordinate space and are relative to the coordinate
 * system origin of this graphics context.
 * This method may use an algorithm that calculates a result quickly
 * but which sometimes might return true even if the specified
 * rectangular area does not intersect the clipping area.
 * The specific algorithm employed may thus trade off accuracy for
 * speed, but it will never return false unless it can guarantee
 * that the specified rectangular area does not intersect the
 * current clipping area.
 * The clipping area used by this method can represent the
 * intersection of the user clip as specified through the clip
 * methods of this graphics context as well as the clipping
 * associated with the device or image bounds and window visibility.
 *
 * @param x the x coordinate of the rectangle to test against the clip
 * @param y the y coordinate of the rectangle to test against the clip
 * @param width the width of the rectangle to test against the clip
 * @param height the height of the rectangle to test against the clip
 * @return <code>true</code> if the specified rectangle intersects
 * the bounds of the current clip; <code>false</code>
 * otherwise.
 */
 public boolean hitClip(int x, int y, int width, int height) {
 // Note, this implementation is not very efficient.
 // Subclasses should override this method and calculate
 // the results more directly.
 Rectangle clipRect = getClipBounds();
 if (clipRect == null) {
 return true;
 }
 return clipRect.intersects(x, y, width, height);
 }

 /**
 * Returns the bounding rectangle of the current clipping area.
 * The coordinates in the rectangle are relative to the coordinate
 * system origin of this graphics context. This method differs
 * from {@link #getClipBounds() getClipBounds} in that an existing
 * rectangle is used instead of allocating a new one.
 * This method refers to the user clip, which is independent of the
 * clipping associated with device bounds and window visibility.
 * If no clip has previously been set, or if the clip has been
 * cleared using <code>setClip(null)</code>, this method returns the
 * specified <code>Rectangle</code>.
 * @param r the rectangle where the current clipping area is
 * copied to. Any current values in this rectangle are
 * overwritten.
 * @return the bounding rectangle of the current clipping area.
 */
 public Rectangle getClipBounds(Rectangle r) {
 // Note, this implementation is not very efficient.
 // Subclasses should override this method and avoid
 // the allocation overhead of getClipBounds().
 Rectangle clipRect = getClipBounds();
 if (clipRect != null) {
 r.x = clipRect.x;
 r.y = clipRect.y;
 r.width = clipRect.width;
 r.height = clipRect.height;
 } else if (r == null) {
 throw new NullPointerException("null rectangle parameter");
 }
 return r;
 }
}