graphics.java

用于移动设备上的java虚拟机源代码

     * @param y1 the y coordinate of the start of the line
     * @param x2 the x coordinate of the end of the line
     * @param y2 the y coordinate of the end of the line
     */
    public native void drawLine(int x1, int y1, int x2, int y2);

    /**
     * Fills the specified rectangle with the current color.
     * If either width or height is zero or less,
     * nothing is drawn.
     * @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 #drawRect(int, int, int, int)
     */
    public native void fillRect(int x, int y, int width, int height);
 
    /**
     * Draws the outline of the specified rectangle using the current
     * color and stroke style.
     * The resulting rectangle will cover an area <code>(width + 1)</code>
     * pixels wide by <code>(height + 1)</code> pixels tall.
     * If either width or height is less than
     * zero, nothing is drawn.
     * @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 #fillRect(int, int, int, int)
     */
    public native void drawRect(int x, int y, int width, int height);

    /**
     * Draws the outline of the specified rounded corner rectangle
     * using the current color and stroke style.
     * The resulting rectangle will cover an area <code>(width +
     * 1)</code> pixels wide
     * by <code>(height + 1)</code> pixels tall.
     * If either <code>width</code> or <code>height</code> is less than
     * zero, nothing is drawn.
     * @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 #fillRoundRect(int, int, int, int, int, int)
     */
    public native void drawRoundRect(int x, int y, int width, int height,
                                     int arcWidth, int arcHeight);
 
    /**
     * Fills the specified rounded corner rectangle with the current color.
     * If either <code>width</code> or <code>height</code> is zero or less,
     * nothing is drawn.
     * @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 #drawRoundRect(int, int, int, int, int, int)
     */
    public native void fillRoundRect(int x, int y, int width, int height,
                                     int arcWidth, int arcHeight);
                          
    /**
     * 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 <code>0</code> degrees
     * is at the <code>3</code> 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 (<em>x</em>,&nbsp;<em>y</em>) and whose size is specified by the
     * <code>width</code> and <code>height</code> arguments.
     * <p>
     * If either <code>width</code> or <code>height</code> is zero or less,
     * nothing is drawn.
     *
     * <p> The filled region consists of the &quot;pie wedge&quot;
     * region bounded
     * by the arc
     * segment as if drawn by <code>drawArc()</code>, the radius extending from
     * the center to
     * this arc at <code>startAngle</code> degrees, and radius extending
     * from the
     * center to this arc at <code>startAngle + arcAngle</code> degrees. </p>
     *
     * <p> The angles are specified relative to the non-square extents of
     * the bounding rectangle such that <code>45</code> 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. </p>
     *
     * @param x the <em>x</em> coordinate of the upper-left corner of
     * the arc to be filled.
     * @param y the <em>y</em> 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 #drawArc(int, int, int, int, int, int)
     */
    public native void fillArc(int x, int y, int width, int height,
                               int startAngle, int arcAngle);

    /**
     * Draws the outline of a circular or elliptical arc
     * covering the specified rectangle,
     * using the current color and stroke style.
     * <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 <code>0</code>&nbsp;degrees
     * is at the <code>3</code>&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 (<em>x</em>,&nbsp;<em>y</em>) 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.
     * If either <code>width</code> or <code>height</code> is less than zero,
     * nothing is drawn.
     *
     * <p> The angles are specified relative to the non-square extents of
     * the bounding rectangle such that <code>45</code> 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. </p>
     *
     * @param x the <em>x</em> coordinate of the upper-left corner
     * of the arc to be drawn
     * @param y the <em>y</em> 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 #fillArc(int, int, int, int, int, int)
     */
    public native void drawArc(int x, int y, int width, int height,
                               int startAngle, int arcAngle);

    /**
     * Draws the specified <code>String</code> using the current font and color.
     * The <code>x,y</code> position is the position of the anchor point.
     * See <a href="#anchor">anchor points</a>.
     * @param str the <code>String</code> to be drawn
     * @param x the x coordinate of the anchor point
     * @param y the y coordinate of the anchor point
     * @param anchor the anchor point for positioning the text
     * @throws NullPointerException if <code>str</code> is <code>null</code>
     * @throws IllegalArgumentException if anchor is not a legal value
     * @see #drawChars(char[], int, int, int, int, int)
     */
    public native void drawString(java.lang.String str,
                                  int x, int y, int anchor);

    /**
     * Draws the specified <code>String</code> using the current font and color.
     * The <code>x,y</code> position is the position of the anchor point.
     * See <a href="#anchor">anchor points</a>.
     *
     * <p>The <code>offset</code> and <code>len</code> parameters must
     * specify a valid range of characters within
     * the string <code>str</code>.
     * The <code>offset</code> parameter must be within the
     * range <code>[0..(str.length())]</code>, inclusive.
     * The <code>len</code> parameter
     * must be a non-negative integer such that
     * <code>(offset + len) &lt;= str.length()</code>.</p>
     *
     * @param str the <code>String</code> to be drawn
     * @param offset zero-based index of first character in the substring
     * @param len length of the substring
     * @param x the x coordinate of the anchor point
     * @param y the y coordinate of the anchor point
     * @param anchor the anchor point for positioning the text
     * @see #drawString(String, int, int, int).
     * @throws StringIndexOutOfBoundsException if <code>offset</code>
     * and <code>length</code> do not specify
     * a valid range within the <code>String</code> <code>str</code>
     * @throws IllegalArgumentException if <code>anchor</code>
     * is not a legal value
     * @throws NullPointerException if <code>str</code> is <code>null</code>
     */
    public native void drawSubstring(String str, int offset, int len,
                                     int x, int y, int anchor);

    /**
     * Draws the specified character using the current font and color.
     * @param character the character to be drawn
     * @param x the x coordinate of the anchor point
     * @param y the y coordinate of the anchor point
     * @param anchor the anchor point for positioning the text; see
     * <a href="#anchor">anchor points</a>
     *
     * @throws IllegalArgumentException if <code>anchor</code>
     * is not a legal value
     *
     * @see #drawString(java.lang.String, int, int, int)
     * @see #drawChars(char[], int, int, int, int, int)
     */
    public native void drawChar(char character, int x, int y, int anchor);

    /**
     * Draws the specified characters using the current font and color.
     *
     * <p>The <code>offset</code> and <code>length</code> parameters must
     * specify a valid range of characters within
     * the character array <code>data</code>.
     * The <code>offset</code> parameter must be within the
     * range <code>[0..(data.length)]</code>, inclusive.
     * The <code>length</code> parameter
     * must be a non-negative integer such that
     * <code>(offset + length) &lt;= data.length</code>.</p>
     *
     * @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 anchor point
     * @param y the y coordinate of the anchor point
     * @param anchor the anchor point for positioning the text; see
     * <a href="#anchor">anchor points</a>
     *
     * @throws ArrayIndexOutOfBoundsException if <code>offset</code>
     * and <code>length</code>
     * do not specify a valid range within the data array
     * @throws IllegalArgumentException if anchor is not a legal value
     * @throws NullPointerException if <code>data</code> is <code>null</code>
     *
     * @see #drawString(java.lang.String, int, int, int)
     */
    public native void drawChars(char[] data, int offset, int length,
                                 int x, int y, int anchor);
 
    /**
     * Draws the specified image by using the anchor point.
     * The image can be drawn in different positions relative to
     * the anchor point by passing the appropriate position constants.
     * See <a href="#anchor">anchor points</a>.
     *
     * <p>If the source image contains transparent pixels, the corresponding
     * pixels in the destination image must be left untouched.  If the source
     * image contains partially transparent pixels, a compositing operation 
     * must be performed with the destination pixels, leaving all pixels of 
     * the destination image fully opaque.</p>
     *
     * <p>If <code>img</code> is the same as the destination of this Graphics
     * object, the result is undefined.  For copying areas within an
     * <code>Image</code>, {@link #copyArea copyArea} should be used instead.
     * </p>
     *
     * @param img the specified image to be drawn
     * @param x the x coordinate of the anchor point
     * @param y the y coordinate of the anchor point
     * @param anchor the anchor point for positioning the image
     * @throws IllegalArgumentException if <code>anchor</code>
     * is not a legal value
     * @throws NullPointerException if <code>img</code> is <code>null</code>
     * @see Image
     */
    public native void drawImage(Image img, int x, int y, int anchor);

    /**
     * Copies a region of the specified source image to a location within
     * the destination, possibly transforming (rotating and reflecting)
     * the image data using the chosen transform function.
     *
     * <p>The destination, if it is an image, must not be the same image as
     * the source image.  If it is, an exception is thrown.  This restriction
     * is present in order to avoid ill-defined behaviors that might occur if
     * overlapped, transformed copies were permitted.</p>
     *
     * <p>The transform function used must be one of the following, as defined
     * in the {@link javax.microedition.lcdui.game.Sprite Sprite} class:<br>
     *
     * <code>Sprite.TRANS_NONE</code> - causes the specified image
     * region to be copied unchanged<br>
     * <code>Sprite.TRANS_ROT90</code> - causes the specified image
     * region to be rotated clockwise by 90 degrees.<br>
     * <code>Sprite.TRANS_ROT180</code> - causes the specified image
     * region to be rotated clockwise by 180 degrees.<br>
     * <code>Sprite.TRANS_ROT270</code> - causes the specified image
     * region to be rotated clockwise by 270 degrees.<br>
     * <code>Sprite.TRANS_MIRROR</code> - causes the specified image
     * region to be reflected about its vertical center.<br>
     * <code>Sprite.TRANS_MIRROR_ROT90</code> - causes the specified image
     * region to be reflected about its vertical center and then rotated
     * clockwise by 90 degrees.<br>
     * <code>Sprite.TRANS_MIRROR_ROT180</code> - causes the specified image
     * region to be reflected about its vertical center and then rotated
     * clockwise by 180 degrees.<br>
     * <code>Sprite.TRANS_MIRROR_ROT270</code> - causes the specified image
     * region to be reflected about its vertical center and then rotated
     * clockwise by 270 degrees.<br></p>
     *
     * <p>If the source region contains transparent pixels, the corresponding
     * pixels in the destination region must be left untouched.  If the source
     * region contains partially transparent pixels, a compositing operation
     * must be performed with the destination pixels, leaving all pixels of
     * the destination region fully opaque.</p>
     *
     * <p> The <code>(x_src, y_src)</code> coordinates are relative to
     * the upper left
     * corner of the source image.  The <code>x_src</code>,
     * <code>y_src</code>, <code>width</code>, and <code>height</code>