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Java AWT

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java.awt Reference
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Graphics

Name

Graphics

[Graphic: Figure from the text]

Description

The Graphics class is an abstract class that represents an object on which you can draw. The concrete classes that are actually used to represent graphics objects are platform dependent, but because they extend the Graphics class, must implement the methods here.

Class Definition

public abstract class java.awt.Graphics
    extends java.lang.Object {
  
  // Constructors
  protected Graphics();
  
  // Instance Methods
  public abstract void clearRect (int x, int y, int width, int height);
  public abstract void clipRect (int x, int y, int width, int height);
  public abstract void copyArea (int x, int y, int width, int height, 
      int deltax, int deltay);
  public abstract Graphics create();
  public Graphics create (int x, int y, int width, int height);
  public abstract void dispose();
  public void draw3DRect (int x, int y, int width, int height, 
      boolean raised);
  public abstract void drawArc (int x, int y, int width, int height, 
      int startAngle, int arcAngle);
  public void drawBytes (byte text[], int offset, int length, 
      int x, int y);
  public void drawChars (char text[], int offset, int length, 
      int x, int y);
  public abstract boolean drawImage (Image image, int x, int y, 
      ImageObserver observer);
  public abstract boolean drawImage (Image image, int x, int y, 
      int width, int height, ImageObserver observer);
  public abstract boolean drawImage (Image image, int x, int y, 
      Color backgroundColor, ImageObserver observer);
  public abstract boolean drawImage (Image image, int x, int y, 
      int width, int height, Color backgroundColor, ImageObserver observer);
  public abstract boolean drawImage(Image img, int dx1, int dy1, 
      int dx2, int dy2, int sx1, int sy1, int sx2, int sy2, ImageObserver 
      observer); (New)
  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); (New)
  public abstract void drawLine (int x1, int y1, int x2, int y2);
  public abstract void drawOval (int x, int y, int width, int height);
  public abstract void drawPolygon (int xPoints[], int yPoints[], 
      int numPoints);
  public void drawPolygon (Polygon p);
  public abstract void drawPolyline(int[ ] xPoints, int[ ] yPoints, 
      int nPoints); (New)
  public void drawRect (int x, int y, int width, int height);
  public abstract void drawRoundRect (int x, int y, int width, 
      int height, int arcWidth, int arcHeight);
  public abstract void drawString (String text, int x, int y);
  public void fill3DRect (int x, int y, int width, int height, 
      boolean raised);
  public abstract void fillArc (int x, int y, int width, int height, 
      int startAngle, int arcAngle);
  public abstract void fillOval (int x, int y, int width, int height);
  public abstract void fillPolygon (int xPoints[], int yPoints[], 
      int numPoints);
  public void fillPolygon (Polygon p);
  public abstract void fillRect (int x, int y, int width, int height);
  public abstract void fillRoundRect (int x, int y, int width, 
      int height, int arcWidth, int arcHeight);
  public void finalize();
  public abstract Shape getClip(); (New)
  public abstract Rectangle getClipBounds(); (New)
  public abstract Rectangle getClipRect();
  public abstract Color getColor();
  public abstract Font getFont();
  public FontMetrics getFontMetrics();
  public abstract FontMetrics getFontMetrics (Font font);
  public abstract void setClip (int x, int y, int width, int height); (New)
  public abstract void setClip (Shape clip); (New)
  public abstract void setColor (Color color);
  public abstract void setFont (Font font);
  public abstract void setPaintMode();
  public abstract void setXORMode (Color xorColor);
  public String toString();
  public abstract void translate (int x, int y);
}

Constructors

Graphics

protected Graphics()

Description

Called by constructors of platform specific subclasses.

Instance Methods

clearRect

public abstract void clearRect (int x, int y, int width, int height)

Parameters

x

x coordinate of origin of area to clear.

y

y coordinate of origin of area to clear.

width

size in horizontal direction to clear.

height

size in vertical direction to clear.

Description

Resets a rectangular area to the background color.

clipRect

public abstract void clipRect (int x, int y, int width, int height)

Parameters

x

x coordinate of origin of clipped area.

y

y coordinate of origin of clipped area.

width

size in horizontal direction to clip.

height

size in vertical direction to clip.

Description

Reduces the drawing area to the intersection of the current drawing area and the rectangular area defined by x, y, width, and height.

copyArea

public abstract void copyArea (int x, int y, int width, int height, int deltax, int deltay)

Parameters

x

x coordinate of origin of area to copy.

y

y coordinate of origin of area to copy.

width

size in horizontal direction to copy.

height

size in vertical direction to copy.

deltax

offset in horizontal direction to copy area to.

deltay

offset in vertical direction to copy area to.

Description

Copies a rectangular area to a new area, whose top left corner is (x+deltax, y+deltay).

create

public abstract Graphics create()

Returns

New graphics context.

Description

Creates a second reference to the same graphics context.

public Graphics create (int x, int y, int width, int height)

Parameters

x

x coordinate of origin of new graphics context.

y

y coordinate of origin of new graphics context.

width

size in horizontal direction.

height

size in vertical direction.

Returns

New graphics context

Description

Creates a second reference to a subset of the same graphics context.

dispose

public abstract void dispose()

Description

Frees system resources used by graphics context.

draw3DRect

public void draw3DRect (int x, int y, int width, int height, boolean raised)

Parameters

x

x coordinate of the rectangle origin.

y

y coordinate of the rectangle origin

width

Width of the rectangle to draw.

height

Height of the rectangle to draw.

raised

Determines if rectangle drawn is raised or not; true for a raised rectangle.

Description

Draws an unfilled 3-D rectangle from (x, y) of size width x height.

drawArc

public abstract void drawArc (int x, int y, int width, int height, int startAngle, int arcAngle)

Parameters

x

x coordinate of the bounding rectangle's origin.

y

y coordinate of the bounding rectangle's origin

width

Width of the bounding rectangle for the arc.

height

Height of the bounding rectangle for the arc.

startAngle

Angle at which arc begins, in degrees

arcAngle

length of arc, in degrees

Description

Draws an unfilled arc from startAngle to arcAngle within bounding rectangle from (x, y) of size width x height. Zero degrees is at three o'clock; positive angles are counter clockwise.

drawBytes

public void drawBytes (byte text[], int offset, int length, int x, int y)

Parameters

text

Text to draw, as a byte array.

offset

Starting position within text to draw.

length

Number of bytes to draw.

x

x coordinate of baseline origin.

y

y coordinate of baseline origin.

Throws

ArrayIndexOutOfBoundsException

If offset or length is invalid.

Description

Draws text on screen, starting with text[offset] and ending with text[offset+length-1].

drawChars

public void drawChars (char text[], int offset, int length, int x, int y)

Parameters

text

Text to draw, as a char array.

offset

Starting position within text to draw.

length

Number of bytes to draw.

x

x coordinate of baseline origin.

y

y coordinate of baseline origin.

Throws

ArrayIndexOutOfBoundsException

If offset or length is invalid.

Description

Draws text on screen, starting with text[offset] and ending with text[offset+length-1].

drawImage

public abstract boolean drawImage (Image image, int x, int y, ImageObserver observer)

Parameters

image

Image to draw.

x

x coordinate of image origin.

y

y coordinate of image origin.

observer

Object that watches for image information; almost always this.

Returns

true if the image has fully loaded when the method returns, false otherwise.

Description

Draws image to screen at (x, y), at its original size. Drawing may be asynchronous. If image is not fully loaded when the method returns, observer is notified when additional information made available.

public abstract boolean drawImage (Image image, int x, int y, int width, int height, ImageObserver observer)

Parameters

image

Image to draw.

x

x coordinate of image origin.

y

y coordinate of image origin.

width

New image size in horizontal direction.

height

New image size in vertical direction.

observer

Object that watches for image information; almost always this.

Returns

true if the image has fully loaded when the method returns, false otherwise.

Description

Draws image to screen at (x, y), scaled to width x height. Drawing may be asynchronous. If image is not fully loaded when the method returns, observer is notified when additional information made available.

public abstract boolean drawImage (Image image, int x, int y, Color backgroundColor, ImageObserver observer)

Parameters

image

Image to draw.

x

x coordinate of image origin.

y

y coordinate of image origin.

backgroundColor

Color to show through image where transparent.

observer

Object that watches for image information; almost always this.

Returns

true if the image has fully loaded when the method returns, false otherwise.

Description

Draws image to screen at (x, y), at its original size. Drawing may be asynchronous. If image is not fully loaded when the method returns, observer is notified when additional information made available. The background color is visible through any transparent pixels.

public abstract boolean drawImage (Image image, int x, int y, int width, int height, Color backgroundColor, ImageObserver observer)

Parameters

image

Image to draw.

x

x coordinate of image origin.

y

y coordinate of image origin.

width

New image size in horizontal direction.

height

New image size in vertical direction.

backgroundColor

Color to show through image where transparent.

observer

Object that watches for image information; almost always this.

Returns

true if the image has fully loaded when the method returns, false otherwise.

Description

Draws image to screen at (x, y), scaled to width x height. Drawing may be asynchronous. If image is not fully loaded when the method returns, observer is notified when additional information made available. The background color is visible through any transparent pixels.

public abstract boolean drawImage (Image image, int dx1, int dy1, int dx2, int dy2, int sx1, int sy1, int sx2, int sy2, ImageObserver observer) (New)

Parameters

image

Image to draw.

dx1

x coordinate of one corner of destination (device) rectangle.

dy1

y coordinate of one corner of destination (device) rectangle.

dx2

x coordinate of the opposite corner of destination (device) rectangle.

dy2

y coordinate of the opposite corner of destination (device) rectangle.

sx1

x coordinate of one corner of source (image) rectangle.

sy1

y coordinate of one corner of source (image) rectangle.

sx2

x coordinate of the opposite corner of source (image) rectangle.

sy2

y coordinate of the opposite corner of source (image) rectangle.

observer

Object that watches for image information; almost always this.

Returns

true if the image has fully loaded when the method returns, false otherwise.

Description

Draws the part of image described by dx1, dy1, dx2, and dy2 to the screen into the rectangle described by sx1, sy1, sx2, and sy2. Drawing may be asynchronous. If image is not fully loaded when the method returns, observer is notified when additional information is made available.

public abstract boolean drawImage (Image image, int dx1, int dy1, int dx2, int dy2, int sx1, int sy1, int sx2, int sy2, Color backgroundColor, ImageObserver observer) (New)

Parameters

image

Image to draw.

dx1

x coordinate of one corner of destination (device) rectangle.

dy1

y coordinate of one corner of destination (device) rectangle.

dx2

x coordinate of the opposite corner of destination (device) rectangle.

dy2

y coordinate of the opposite corner of destination (device) rectangle.

sx1

x coordinate of one corner of source (image) rectangle.

sy1

y coordinate of one corner of source (image) rectangle.

sx2

x coordinate of the opposite corner of source (image) rectangle.

sy2

y coordinate of the opposite corner of source (image) rectangle.

backgroundColor

Color to show through image where transparent.

observer

Object that watches for image information; almost always this.

Returns

true if the image has fully loaded when the method returns, false otherwise.

Description

Draws the part of image described by dx1, dy1, dx2, and dy2 to the screen into the rectangle described by sx1, sy1, sx2, and sy2. Drawing may be asynchronous. If image is not fully loaded when the method returns, observer is notified when additional information made available. The background color is visible through any transparent pixels.

drawLine

public abstract void drawLine (int x1, int y1, int x2, int y2)

Parameters

x1

x coordinate of one point on line.

y1

y coordinate of one point on line.

x2

x coordinate of the opposite point on line.

y2

y coordinate of the opposite point on line.

Description

Draws a line connecting (x1, y1) and (x2, y2).

drawOval

public abstract void drawOval (int x, int y, int width, int height)

Parameters

x

x coordinate of bounding rectangle origin.

y

y coordinate of bounding rectangle origin

width

Width of bounding rectangle to draw in.

height

Height of bounding rectangle to draw in.

Description

Draws an unfilled oval within bounding rectangle from (x, y) of size width x height.

drawPolygon

public abstract void drawPolygon (int xPoints[], int yPoints[], int numPoints)

Parameters

xPoints[]

The array of x coordinates for each point.

yPoints[]

The array of y coordinates for each point.

numPoints

The number of elements in both xPoints and yPoints arrays to use.

Description

Draws an unfilled polygon based on first numPoints elements in xPoints and yPoints.

public void drawPolygon (Polygon p)

Parameters

p

Points of object to draw.

Description

Draws an unfilled polygon based on points within the Polygon p.

drawPolyline

public abstract void drawPolyline (int xPoints[], int yPoints[], int nPoints) (New)

Parameters

xPoints[]

The array of x coordinates for each point.

yPoints[]

The array of y coordinates for each point.

nPoints

The number of elements in both xPoints and yPoints arrays to use.

Description

Draws a series of line segments based on first numPoints elements in xPoints and yPoints.

drawRect

public void drawRect (int x, int y, int width, int height)

Parameters

x

x coordinate of rectangle origin.

y

y coordinate of rectangle origin

width

Width of rectangle to draw.

height

Height of rectangle to draw.

Description

Draws an unfilled rectangle from (x, y) of size width x height.

drawRoundRect

public abstract void drawRoundRect (int x, int y, int width, int height, int arcWidth, int arcHeight)

Parameters

x

x coordinate of bounding rectangle origin.

y

y coordinate of bounding rectangle origin

width

Width of rectangle to draw.

height

Height of rectangle to draw.

arcWidth

Width of arc of rectangle corner.

arcHeight

Height of arc of rectangle corner.

Description

Draws an unfilled rectangle from (x, y) of size width x height with rounded corners.

drawString

public abstract void drawString (String text, int x, int y)

Parameters

text

Text to draw.

x

x coordinate of baseline origin.

y

y coordinate of baseline origin.

Description

Draws text on screen.

fill3DRect

public void fill3DRect (int x, int y, int width, int height, boolean raised)

Parameters

x

x coordinate of rectangle origin.

y

y coordinate of rectangle origin

width

Width of rectangle to draw.

height

Height of rectangle to draw.

raised

true to draw a rectangle that appears raised; false to draw a rectangle that appears depressed.

Description

Draws a filled 3-D rectangle from (x, y) of size width x height.

fillArc

public abstract void fillArc (int x, int y, int width, int height, int startAngle, int arcAngle)

Parameters

x

x coordinate of bounding rectangle origin.

y

y coordinate of bounding rectangle origin

width

Width of bounding rectangle to draw in.

height

Height of bounding rectangle to draw in.

startAngle

Starting angle of arc.

arcAngle

The extent of the arc, measured from startAngle

Description

Draws a filled arc from startAngle to arcAngle within bounding rectangle from (x, y) of size width x height. Zero degrees is at three o'clock; positive angles are counter clockwise.

fillOval

public abstract void fillOval (int x, int y, int width, int height)

Parameters

x

x coordinate of bounding rectangle origin.

y

y coordinate of bounding rectangle origin

width

Width of bounding rectangle to draw in.

height

Height of bounding rectangle to draw in.

Description

Draws filled oval within bounding rectangle from (x, y) of size width x height.

fillPolygon

public abstract void fillPolygon (int xPoints[], int yPoints[], int numPoints)

Parameters

xPoints[]

The array of x coordinates for each point.

yPoints[]

The array of y coordinates for each point.

numPoints

The number of elements in both xPoints and yPoints arrays to use.

Throws

ArrayIndexOutOfBoundsException

If numPoints > xPoints.length or numPoints > yPoints.length.

Description

Draws filled polygon based on first numPoints elements in xPoints and yPoints.

public void fillPolygon (Polygon p)

Parameters

p

Points of object to draw.

Description

Draws filled polygon based on points within the Polygon p.

fillRect

public abstract void fillRect (int x, int y, int width, int height)

Parameters

x

x coordinate of rectangle origin.

y

y coordinate of rectangle origin

width

Width of rectangle to draw.

height

Height of rectangle to draw.

Description

Draws filled rectangle from (x, y) of size width x height.

fillRoundRect

public abstract void fillRoundRect (int x, int y, int width, int height, int arcWidth, int arcHeight)

Parameters

x

x coordinate of bounding rectangle origin.

y

y coordinate of bounding rectangle origin

width

Width of rectangle to draw.

height

Height of rectangle to draw.

arcWidth

Width of arc of rectangle corner.

arcHeight

Height of arc of rectangle corner.

Description

Draws a filled rectangle from (x, y) of size width x height with rounded corners.

finalize

public void finalize()

Overrides

Object.finalize()

Description

Tells the garbage collector to dispose of graphics context.

getClip

public abstract Shape getClip () (New)

Returns

Shape describing the clipping are of the graphics context.

getClipBounds

public abstract Rectangle getClipBounds() (New)

Returns

Rectangle describing the clipping area of the graphics context.

getClipRect

public abstract Rectangle getClipRect() (Deprecated)

Returns

Replaced by getClipBounds().

getColor

public abstract Color getColor()

Returns

The current drawing Color of the graphics context.

getFont

public abstract Font getFont()

Returns

The current Font of the graphics context.

getFontMetrics

public FontMetrics getFontMetrics()

Returns

The FontMetrics of the current font of the graphics context.

public abstract FontMetrics getFontMetrics (Font font)

Parameters

font

Font to get metrics for.

Returns

The FontMetrics of the given font for the graphics context.

setClip

public abstract void setClip (int x, int y, int width, int height) (New)

Parameters

x

x coordinate of rectangle

y

y coordinate of rectangle

width

width of rectangle

height

height of rectangle

Description

Changes current clipping region to the specified rectangle.

public abstract void setClip (Shape clip) (New)

Parameters

clip

The new clipping shape.

Description

Changes current clipping region to the specified shape.

setColor

public abstract void setColor (Color color)

Parameters

color

New color.

Description

Changes current drawing color of graphics context.

setFont

public abstract void setFont (Font font)

Parameters

font

New font.

Description

Changes current font of graphics context.

setPaintMode

public abstract void setPaintMode()

Description

Changes painting mode to normal mode.

setXORMode

public abstract void setXORMode (Color xorColor)

Parameters

xorColor

XOR mode drawing color.

Description

Changes painting mode to XOR mode; in this mode, drawing the same object in the same color at the same location twice has no net effect.

toString

public String toString()

Returns

A string representation of the Graphics object.

Overrides

Object.toString()

translate

public void translate (int x, int y)

Parameters

x

x coordinate of new drawing origin.

y

y coordinate of new drawing origin.

Description

Moves the origin of drawing operations to (x, y).

See Also

Color, Font, FontMetrics, Image, ImageObserver, Object, Polygon, Rectangle, Shape, String


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