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Java Source | 1999-05-28 | 51.5 KB | 1,132 lines | [TEXT/CWIE]

/* * @(#)Graphics.java 1.49 98/07/22 * * Copyright 1995-1998 by Sun Microsystems, Inc., * 901 San Antonio Road, Palo Alto, California, 94303, U.S.A. * All rights reserved. * * This software is the confidential and proprietary information * of Sun Microsystems, Inc. ("Confidential Information"). You * shall not disclose such Confidential Information and shall use * it only in accordance with the terms of the license agreement * you entered into with Sun. */ 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. * * 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> * * Coordinates are infinitely thin and lie between the pixels of the * output device. * Operations which 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 which fill a figure operate by filling the interior * of that infinitely thin path. * Operations which render horizontal text render the ascending * portion of character glyphs entirely above the baseline coordinate. * * 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 y coordinate as * the baseline of a line of text, that line is drawn entirely below * the text, except for any descenders. * </ul> * All coordinates which 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. * All rendering operations modify only pixels which lie within the * area bounded by both the current clip of the graphics context * and the extents of the component used to create the * <code>Graphics</code> object. * All drawing or writing is done in the current color, * using the current paint mode, and in the current font. * * @version 1.49, 07/22/98 * @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 contructor for a graphics * context. * * 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 (x, y). * 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 (x, y). * That is to say, the point (<code>0</code>, <code>0</code>) in the * new graphics context is the same as (x, y) 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>, <code>0</code>), and its size * is specified by the <code>width</code> and <code>height</code> arguments. * </ul> * * @param x the x coordinate. * @param y the y 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(); g.translate(x, y); g.clipRect(0, 0, width, height); return g; } /** * Translates the origin of the graphics context to the point * (x, y) in the current coordinate system. * Modifies this graphics context so that its new origin corresponds * to the point (x, y) 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 x coordinate. * @param y the y 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 */ 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. * * When drawing operations are performed, pixels which are the * current color are changed to the specified color, and vice versa. * * 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 */ 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. * @param font the font. * @see java.awt.Graphics#getFont * @see java.awt.Graphics#drawChars(java.lang.String, int, int) * @see java.awt.Graphics#drawString(byte[], int, int, int, int) * @see java.awt.Graphics#drawBytes(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. * 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. * @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. * 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. * Rendering operations have no effect outside of the clipping area. * @param x the x coordinate of the new clip rectangle. * @param y the y 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) * @since JDK1.1 */ public abstract void setClip(int x, int y, int width, int height); /** * Gets the current clipping area. * @return a <code>Shape</code> object representing the * current clipping area. * @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 which implement the <code>Shape</code> * interface can be used to set the clip. The only * <code>Shape</code> objects which are guaranteed to be * supported are <code>Shape</code> objects which are * obtained via the <code>getClip</code> method and via * <code>Rectangle</code> objects. * @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 x coordinate of the source rectangle. * @param y the y 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, y1)</code> and <code>(x2, y2)</code> * in this graphics context's coordinate system. * @param x1 the first point's x coordinate. * @param y1 the first point's y coordinate. * @param x2 the second point's x coordinate. * @param y2 the second point's y 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 + width - 1</code>. * The top and bottom edges are at * <code>y</code> and <code>y + height - 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 x coordinate * of the rectangle to be filled. * @param y the y 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 + width</code>. * The top and bottom edges are at * <code>y</code> and <code>y + height</code>. * The rectangle is drawn using the graphics context's current color. * @param x the x coordinate * of the rectangle to be drawn. * @param y the y 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. * * Beginning with Java 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 x coordinate of the rectangle to clear. * @param y the y 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 + width</code>, * respectively. The top and bottom edges of the rectangle are at * <code>y</code> and <code>y + height</code>. * @param x the x coordinate of the rectangle to be drawn. * @param y the y 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 + width - 1</code>, * respectively. The top and bottom edges of the rectangle are at * <code>y</code> and <code>y + height - 1</code>. * @param x the x coordinate of the rectangle to be filled. * @param y the y 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. * * The colors used for the highlighting effect are determined * based on the current color. * The resulting rectangle covers an area that is * <code>width + 1</code> pixels wide * by <code>height + 1</code> pixels tall. * @param x the x coordinate of the rectangle to be drawn. * @param y the y 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 x coordinate of the rectangle to be filled. * @param y the y 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. * * The oval covers an area that is * <code>width + 1</code> pixels wide * and <code>height + 1</code> pixels tall. * @param x the x coordinate of the upper left * corner of the oval to be drawn. * @param y the y 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 x coordinate of the upper left corner * of the oval to be filled. * @param y the y 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. * * 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 degrees * is at the 3 o'clock position. * A positive value indicates a counter-clockwise rotation * while a negative value indicates a clockwise rotation. * * The center of the arc is the center of the rectangle whose origin * is (x, y) and whose size is specified by the * <code>width</code> and <code>height</code> arguments. * * The resulting arc covers an area * <code>width + 1</code> pixels wide * by <code>height + 1</code> pixels tall. * * 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 x coordinate of the * upper-left corner of the arc to be drawn. * @param y the y 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. * * The resulting arc begins at <code>startAngle</code> and extends * for <code>arcAngle</code> degrees. * Angles are interpreted such that 0 degrees * is at the 3 o'clock position. * A positive value indicates a counter-clockwise rotation * while a negative value indicates a clockwise rotation. * * The center of the arc is the center of the rectangle whose origin * is (x, y) and whose size is specified by the * <code>width</code> and <code>height</code> arguments. * * The resulting arc covers an area * <code>width + 1</code> pixels wide * by <code>height + 1</code> pixels tall. * * 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 x coordinate of the * upper-left corner of the arc to be filled. * @param y the y 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 x and y coordinates. * Each pair of (x, y) coordinates defines a point. * The figure is not closed if the first point * differs from the last point. * @param xPoints an array of x points * @param yPoints an array of y 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 x and y coordinates. * Each pair of (x, y) coordinates defines a point. * * This method draws the polygon defined by <code>nPoint</code> line * segments, where the first <code>nPoint - 1</code> * line segments are line segments from * <code>(xPoints[i - 1], yPoints[i - 1])</code> * to <code>(xPoints[i], yPoints[i])</code>, for * 1 ≤ i ≤ <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 x and y coordinates. * * This method draws the polygon defined by <code>nPoint</code> line * segments, where the first <code>nPoint - 1</code> * line segments are line segments from * <code>(xPoints[i - 1], yPoints[i - 1])</code> * to <code>(xPoints[i], yPoints[i])</code>, for * 1 ≤ i ≤ <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. * * 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. * * 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 * first character is at position (x, y) in this * graphics context's coordinate system. * @param str the string to be drawn. * @param x the x coordinate. * @param y the y coordinate. * @see java.awt.Graphics#drawBytes * @see java.awt.Graphics#drawChars */ public abstract void drawString(String str, int x, int y); /** * Draws the text given by the specified iterator, using this * graphics context's current color. The iterator has to specify a font * for each character. The baseline of the * first character is at position (x, y) in this * graphics context's coordinate system. * @param iterator the iterator whose text is to be drawn * @param x the x coordinate. * @param y the y coordinate. * @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 (x, y) 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 x coordinate of the baseline of the text * @param y the y coordinate of the baseline of the text * @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 (x, y) in this * graphics context's coordinate system. * @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 x coordinate of the baseline of the text * @param y the y coordinate of the baseline of the text * @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 * (x, y) in this graphics context's coordinate * space. Transparent pixels in the image do not affect whatever * pixels are already there. * * 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. * * If the image has not yet been completely loaded, then * <code>drawImage</code> returns <code>false</code>. As more of * the image becomes available, the process that draws the image notifies * the specified image observer. * @param img the specified image to be drawn. * @param x the x coordinate. * @param y the y coordinate. * @param observer object to be notified as more of * the image is converted. * @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. * * 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. * * 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 draws the image notifies * the image observer by calling its <code>imageUpdate</code> method. * * 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. * @param x the x coordinate. * @param y the y 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. * @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 * (x, y) in this graphics context's coordinate * space. 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. * * 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. * * If the image has not yet been completely loaded, then * <code>drawImage</code> returns <code>false</code>. As more of * the image becomes available, the process that draws the image notifies * the specified image observer. * @param img the specified image to be drawn. * @param x the x coordinate. * @param y the y 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. * @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. * * 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. * * 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 draws the image notifies * the specified image observer. * * 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. * @param x the x coordinate. * @param y the y 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. * @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. * * 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 draws the image notifies * the specified image observer. * * 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 * @param dx1 the x coordinate of the first corner of the * destination rectangle. * @param dy1 the y coordinate of the first corner of the * destination rectangle. * @param dx2 the x coordinate of the second corner of the * destination rectangle. * @param dy2 the y coordinate of the second corner of the * destination rectangle. * @param sx1 the x coordinate of the first corner of the * source rectangle. * @param sy1 the y coordinate of the first corner of the * source rectangle. * @param sx2 the x coordinate of the second corner of the * source rectangle. * @param sy2 the y coordinate of the second corner of the * source rectangle. * @param observer object to be notified as more of the image is * scaled and converted. * @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. * * 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. * * 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 draws the image notifies * the specified image observer. * * 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 * @param dx1 the x coordinate of the first corner of the * destination rectangle. * @param dy1 the y coordinate of the first corner of the * destination rectangle. * @param dx2 the x coordinate of the second corner of the * destination rectangle. * @param dy2 the y coordinate of the second corner of the * destination rectangle. * @param sx1 the x coordinate of the first corner of the * source rectangle. * @param sy1 the y coordinate of the first corner of the * source rectangle. * @param sx2 the x coordinate of the second corner of the * source rectangle. * @param sy2 the y 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. * @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. * * 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. * * 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() + "]"; } /** * @deprecated As of JDK version 1.1, * replaced by <code>getClipBounds()</code>. */ public Rectangle getClipRect() { return getClipBounds(); } /** * Returns true if the specified rectangular area intersects * the bounding rectangle of the current clipping area. * The coordinates in the rectangle are relative to the coordinate * system origin of this graphics context. * * @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 */ public boolean hitClip(int x, int y, int width, int height) { // FIXME: 1.2 beta3 placeholder, replace for beta4 return new Rectangle(x,y,width,height).intersects(getClipBounds()); } /** * 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 * getClipBounds() in that an existing rectangle is used instead * of allocating a new one. * @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) { // FIXME: 1.2 beta3 placeholder, replace for beta4 Rectangle clipRect = getClipBounds(); r.x = clipRect.x; r.y = clipRect.y; r.width = clipRect.width; r.height = clipRect.height; return r; } }