Java Platform 1.2

java.awt.font
Class TextAttribute

java.lang.Object
  |
  +--java.text.AttributedCharacterIterator.Attribute
        |
        +--java.awt.font.TextAttribute

public final class TextAttribute
extends AttributedCharacterIterator.Attribute

The TextAttribute class defines attribute keys and attribute values used for text rendering.

TextAttribute instances are used as attribute keys to identify attributes in AttributedCharacterIterator, Font, and other classes handling text attributes. Other constants defined in this class are used as attribute values.

For each text attribute, the documentation describes:

Types of Values

Interpolation

See Also:
AttributedCharacterIterator, Font, Serialized Form

Field Summary
static TextAttribute BACKGROUND
          Attribute key for the background Paint adornment.
static TextAttribute BIDI_EMBEDDING
          Attribute key for the embedding level for nested bidirectional runs.
static TextAttribute CHAR_REPLACEMENT
          Attribute key for a user_defined glyph to display in the text in lieu of a character.
static TextAttribute FAMILY
          Attribute key for the unlocalized font family name.
static TextAttribute FONT
          Attribute key for the font to use to render text.
static TextAttribute FOREGROUND
          Attribute key for the foreground paint adornment.
static TextAttribute INPUT_METHOD_HIGHLIGHT
          Attribute key for input method highlight styles.
static TextAttribute JUSTIFICATION
          Attribute key for the justification of a paragraph.
static Float JUSTIFICATION_FULL
          Justify the line to the full requested width.
static Float JUSTIFICATION_NONE
          Do not allow the line to be justified.
static TextAttribute POSTURE
          Attribute key for the posture of a font.
static Float POSTURE_OBLIQUE
          The standard italic posture.
static Float POSTURE_REGULAR
          The standard posture, upright.
static TextAttribute RUN_DIRECTION
          Attribute key for the run direction of the line.
static Boolean RUN_DIRECTION_LTR
          Left-to-right run direction.
static Boolean RUN_DIRECTION_RTL
          Right-to-left run direction.
static TextAttribute SIZE
          Attribute key for the font size.
static TextAttribute STRIKETHROUGH
          Attribute key for the strikethrough adornment.
static Boolean STRIKETHROUGH_ON
          A single strikethrough.
static TextAttribute SUPERSCRIPT
          Attribute key for super and subscripting.
static Integer SUPERSCRIPT_SUB
          Standard subscript.
static Integer SUPERSCRIPT_SUPER
          Standard superscript.
static TextAttribute SWAP_COLORS
          Attribute key for swapping foreground and background Paints (or Colors).
static Boolean SWAP_COLORS_ON
          Swap foreground and background.
static TextAttribute TRANSFORM
          Attribute key for the transform of a font.
static TextAttribute UNDERLINE
          Attribute key for underline adornments.
static Integer UNDERLINE_ON
          Standard underline at the roman baseline for roman text, and below the decenders for other text.
static TextAttribute WEIGHT
          Attribute key for the weight of a font.
static Float WEIGHT_BOLD
          The standard bold weight.
static Float WEIGHT_DEMIBOLD
          A moderately lighter weight than BOLD.
static Float WEIGHT_DEMILIGHT
          An intermediate weight between LIGHT and STANDARD.
static Float WEIGHT_EXTRA_LIGHT
          The lightest predefined weight.
static Float WEIGHT_EXTRABOLD
          An extra heavy weight.
static Float WEIGHT_HEAVY
          A moderately heavier weight than BOLD.
static Float WEIGHT_LIGHT
          The standard light weight.
static Float WEIGHT_MEDIUM
          An intermediate weight between the REGULAR and BOLD weights.
static Float WEIGHT_REGULAR
          The standard weight.
static Float WEIGHT_SEMIBOLD
          A moderately heavier weight than REGULAR.
static Float WEIGHT_ULTRABOLD
          The heaviest predefined weight.
static TextAttribute WIDTH
          Attribute key for the width of a font.
static Float WIDTH_CONDENSED
          The most condensed predefined width.
static Float WIDTH_EXTENDED
          The most extended predefined width.
static Float WIDTH_REGULAR
          The standard width.
static Float WIDTH_SEMI_CONDENSED
          A moderately condensed width.
static Float WIDTH_SEMI_EXTENDED
          A moderately extended width.
 
Fields inherited from class java.text.AttributedCharacterIterator.Attribute
INPUT_METHOD_SEGMENT, LANGUAGE, READING
 
Constructor Summary
protected TextAttribute(String name)
          Constructs a TextAttribute with the specified name.
 
Method Summary
protected  Object readResolve()
          Resolves instances being deserialized to the predefined constants.
 
Methods inherited from class java.text.AttributedCharacterIterator.Attribute
equals, getName, hashCode, toString
 
Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
 

Field Detail

FAMILY

public static final TextAttribute FAMILY
Attribute key for the unlocalized font family name.

Key

FAMILY

Value

String

Constants

"Serif", "SansSerif"

Default

Host default;

Description

The name of the font family. If the family name is not found, the default font is used. The name should not be the full font name or specify other attributes (such as the name "Helvetica Bold"). Such names might result in the default font if the name does not match a known family name.

WEIGHT

public static final TextAttribute WEIGHT
Attribute key for the weight of a font.

Key

WEIGHT

Value

Float

Constants

WEIGHT_ULTRA_LIGHT = 0.25,
WEIGHT_EXTRA_LIGHT = 0.5,
WEIGHT_LIGHT = 0.75,
WEIGHT_DEMILIGHT = 0.875,
WEIGHT_REGULAR = 1.0,
WEIGHT_SEMIBOLD = 1.25,
WEIGHT_MEDIUM = 1.5,
WEIGHT_DEMIBOLD = 1.75,
WEIGHT_BOLD = 2.0,
WEIGHT_HEAVY = 2.25,
WEIGHT_EXTRABOLD = 2.5,
WEIGHT_ULTRABOLD = 2.75

Default

WEIGHT_REGULAR

Description

The value is roughly the ratio of the stem width to that of the regular weight. If the font has a different value for specific constants, then the value is interpolated as described in the class description.

Fallback

Currently none. However, in the future, shape manipulations might be
available to simulate weight variations for fonts that don't have them.


WEIGHT_EXTRA_LIGHT

public static final Float WEIGHT_EXTRA_LIGHT
The lightest predefined weight.
See Also:
WEIGHT

WEIGHT_LIGHT

public static final Float WEIGHT_LIGHT
The standard light weight.
See Also:
WEIGHT

WEIGHT_DEMILIGHT

public static final Float WEIGHT_DEMILIGHT
An intermediate weight between LIGHT and STANDARD.
See Also:
WEIGHT

WEIGHT_REGULAR

public static final Float WEIGHT_REGULAR
The standard weight. This weight is used if WEIGHT is unspecified.
See Also:
WEIGHT

WEIGHT_SEMIBOLD

public static final Float WEIGHT_SEMIBOLD
A moderately heavier weight than REGULAR.
See Also:
WEIGHT

WEIGHT_MEDIUM

public static final Float WEIGHT_MEDIUM
An intermediate weight between the REGULAR and BOLD weights.
See Also:
WEIGHT

WEIGHT_DEMIBOLD

public static final Float WEIGHT_DEMIBOLD
A moderately lighter weight than BOLD.
See Also:
WEIGHT

WEIGHT_BOLD

public static final Float WEIGHT_BOLD
The standard bold weight.
See Also:
WEIGHT

WEIGHT_HEAVY

public static final Float WEIGHT_HEAVY
A moderately heavier weight than BOLD.
See Also:
WEIGHT

WEIGHT_EXTRABOLD

public static final Float WEIGHT_EXTRABOLD
An extra heavy weight.
See Also:
WEIGHT

WEIGHT_ULTRABOLD

public static final Float WEIGHT_ULTRABOLD
The heaviest predefined weight.
See Also:
WEIGHT

WIDTH

public static final TextAttribute WIDTH
Attribute key for the width of a font.

Key

WIDTH

Value

Float

Constants

WIDTH_CONDENSED = 0.75,
WIDTH_SEMI_CONDENSED = 0.875,
WIDTH_REGULAR = 1.0,
WIDTH_SEMI_EXTENDED = 1.25,
WIDTH_EXTENDED = 1.5

Default

WIDTH_REGULAR

Description

The value is roughly the ratio of the advance width to that of the regular width. If the font has a different value for specific constants, then the value is interpolated as described in the class description.

Fallback

If a Narrow font is available and matches, use that. Otherwise scale with a transform based on the value.

WIDTH_CONDENSED

public static final Float WIDTH_CONDENSED
The most condensed predefined width.
See Also:
WIDTH

WIDTH_SEMI_CONDENSED

public static final Float WIDTH_SEMI_CONDENSED
A moderately condensed width.
See Also:
WIDTH

WIDTH_REGULAR

public static final Float WIDTH_REGULAR
The standard width. This width is used if WIDTH is unspecified.
See Also:
WIDTH

WIDTH_SEMI_EXTENDED

public static final Float WIDTH_SEMI_EXTENDED
A moderately extended width.
See Also:
WIDTH

WIDTH_EXTENDED

public static final Float WIDTH_EXTENDED
The most extended predefined width.
See Also:
WIDTH

POSTURE

public static final TextAttribute POSTURE
Attribute key for the posture of a font.

Key

POSTURE

Value

Float

Constants

POSTURE_REGULAR = 0,
POSTURE_OBLIQUE = 0.20

Default

POSTURE_REGULAR

Description

The value is interpreted generally as a skew slope, positive leans to the right. If the font has a different value for specific constants, then the value is interpolated as described in the class description. With fonts that have italic faces, not only the skew of the character changes, but also the letter shapes might change.
Notes:
To set the value by angle, use:
value = new Float(Math.tan(Math.PI*degrees/180.0)
To determine the angle from the value, use:
angle = Math.atan(value.floatValue())*180/Math.PI

Fallback

If an Oblique font is available and matches, use that. Otherwise skew with a transform using the posture value interpreted as run/rise.
See Also:
Font.getItalicAngle()

POSTURE_REGULAR

public static final Float POSTURE_REGULAR
The standard posture, upright.
See Also:
POSTURE

POSTURE_OBLIQUE

public static final Float POSTURE_OBLIQUE
The standard italic posture.
See Also:
POSTURE

SIZE

public static final TextAttribute SIZE
Attribute key for the font size.

Key

SIZE

Value

Float

Default

from System Properties

Description

Represents point size. Note that the appearance and metrics of a 12pt font with a 2X transform might be different than that of a 24 point font with no transform.

Fallback

Scale to provided size.

TRANSFORM

public static final TextAttribute TRANSFORM
Attribute key for the transform of a font.

Key

TRANSFORM

Value

TransformAttribute

Default

Identity transform

Description

Used to transform glyphs rendered by this font. The primary intent is to support scaling, skewing, and translation. In general, large rotations do not produce very useful results. The transform modifies both the glyph and the advance. The translations in the transform are interpreted as a ratio of the point size. That is, with a point size of 12, a translation of 0.5 results in a movement of 6 points.

The advance point of the transformed glyph is the transform of the advance point projected onto the baseline. If the advance ends up to the left (top) of the glyph origin, the two points are swapped.

Example one: The point size is 20, the original advance is 10.0, and the transform is a 60 degree counterclockwise rotation plus an offset up and to the right of 0.1, -0.1. The translation results in an offset of <2.0, -2.0>. The original advance point is <10.0, 0.0>; after the rotation it is <6.0, -8.0>; when adding the offset this becomes <8.0,-10.0>, when projecting on the (horizontal) baseline this becomes the new advance point: <8.0, 0.0>. The advance width is the distance from the origin to the advance point: 8.0. The rotated glyph is rendered two points up and to the right of its origin and rotated. This does not affect the baseline for subsequent glyphs.


SUPERSCRIPT

public static final TextAttribute SUPERSCRIPT
Attribute key for super and subscripting.

Key

SUPERSCRIPT

Value

Integer

Constants

SUPERSCRIPT_NONE = 0,
SUPERSCRIPT_SUPER = 1,
SUPERSCRIPT_SUB = -1

Default

SUPERSCRIPT_NONE

Description

Requests that the font display the characters with glyphs at a particular superscript level: 0 = none, 1 = superscript, 2 = superscript of superscript,...-1 = subscript, -2 = subscript of subscript,... Requests that the font display text using default superscript (or subscript) glyphs and/or scaling.

Fallback

Use transform with translation of +/-1/2 and scale of 2/3, progressively for each level. That is, for the transform at level N (with N != 0):
offset = sign(N)*1/2*(2/3)^(abs(N)-1)
scale = (2/3)^abs(N)

SUPERSCRIPT_SUPER

public static final Integer SUPERSCRIPT_SUPER
Standard superscript.
See Also:
SUPERSCRIPT

SUPERSCRIPT_SUB

public static final Integer SUPERSCRIPT_SUB
Standard subscript.
See Also:
SUPERSCRIPT

FONT

public static final TextAttribute FONT
Attribute key for the font to use to render text.

Key

FONT

Value

Font

Default

None, perform default resolution

Description

A way for users to override the resolution of font attributes into a Font, or force use of a particular Font instance. This also allows users to specify subclasses of Font in cases where a Font can be subclassed.

CHAR_REPLACEMENT

public static final TextAttribute CHAR_REPLACEMENT
Attribute key for a user_defined glyph to display in the text in lieu of a character.

Key

CHAR_REPLACEMENT

Value

GraphicAttribute

Description

Allows the user to specify an empty position plus metric information. This method is used to reserve space for a graphic or other embedded component. Required for correct BIDI position of 'inline' components within a line. An optional convenience method allows drawing for simple cases. Follows the Microsoft model: the character that this is applied to should be ?.

FOREGROUND

public static final TextAttribute FOREGROUND
Attribute key for the foreground paint adornment.

Key

FOREGROUND

Value

Paint

Default

Color.black

Description

Specify the foreground Paint (or Color) of the text.

BACKGROUND

public static final TextAttribute BACKGROUND
Attribute key for the background Paint adornment.

Key

BACKGROUND

Value

Paint

Default

null

Description

Specify the background Paint (or Color) of the text.

UNDERLINE

public static final TextAttribute UNDERLINE
Attribute key for underline adornments.

Key

UNDERLINE

Value

Integer

Constants

UNDERLINE_ON = 0

Default

none

Description

An embellishment added to the glyphs rendered by a font.

Fallback


UNDERLINE_ON

public static final Integer UNDERLINE_ON
Standard underline at the roman baseline for roman text, and below the decenders for other text.
See Also:
UNDERLINE

STRIKETHROUGH

public static final TextAttribute STRIKETHROUGH
Attribute key for the strikethrough adornment.

Key

STRIKETHROUGH

Value

Boolean

Constants

true = on, false = off

Default

off

Description

An embellishment added to the glyphs rendered by a font.

STRIKETHROUGH_ON

public static final Boolean STRIKETHROUGH_ON
A single strikethrough.
See Also:
STRIKETHROUGH

RUN_DIRECTION

public static final TextAttribute RUN_DIRECTION
Attribute key for the run direction of the line.

Key

RUN_DIRECTION

Value

Boolean

Constants

RUN_DIRECTION_LTR = true, RUN_DIRECTION_RTL = false

Default

Use the default Unicode base direction from the BIDI algorithm.

Description

Specifies which base run direction to use when positioning mixed directional runs within a paragraph. If this value is RUN_DIRECTION_DEFAULT, TextLayout uses the default Unicode base direction from the BIDI algorithm.

This attribute should have the same value over the whole paragraph.


RUN_DIRECTION_LTR

public static final Boolean RUN_DIRECTION_LTR
Left-to-right run direction.
See Also:
RUN_DIRECTION

RUN_DIRECTION_RTL

public static final Boolean RUN_DIRECTION_RTL
Right-to-left run direction.
See Also:
RUN_DIRECTION

BIDI_EMBEDDING

public static final TextAttribute BIDI_EMBEDDING
Attribute key for the embedding level for nested bidirectional runs.

Key

BIDI_EMBEDDING

Value

Integer

Limits

Positive values 1 through 15 are embedding levels, negative values
through -15 are override levels

Default

Use standard BIDI to compute levels from formatting characters in the text.

Description

Specifies the bidi embedding level of the character. When this attribute is present anywhere in a paragraph, then the Unicode characters RLO, LRO, RLE, LRE, PDF are disregarded in the BIDI analysis of that paragraph. See the Unicode Standard v. 2.0, section 3-11.

JUSTIFICATION

public static final TextAttribute JUSTIFICATION
Attribute key for the justification of a paragraph.

Key

JUSTIFICATION

Value

Float

Limits

0.0 through1.0

Default

1.0

Description

Specifies which fraction of the extra space to use when justification is requested. For example, if the line is 50 points wide and the margins are 70 points apart, a value of 0.5 means that the line is padded to reach a width of 60 points.

This attribute should have the same value over the whole paragraph.


JUSTIFICATION_FULL

public static final Float JUSTIFICATION_FULL
Justify the line to the full requested width.
See Also:
JUSTIFICATION

JUSTIFICATION_NONE

public static final Float JUSTIFICATION_NONE
Do not allow the line to be justified.
See Also:
JUSTIFICATION

INPUT_METHOD_HIGHLIGHT

public static final TextAttribute INPUT_METHOD_HIGHLIGHT
Attribute key for input method highlight styles.

Values are instances of InputMethodHighlight. These instances should be wrapped in Annotation instances if segments need to be highlighted separately.

Input method highlights are used while text is being composed using an input method. Text editing components should retain them even if they generally only deal with unstyled text, and make them available to the drawing routines.

See Also:
InputMethodHighlight

SWAP_COLORS

public static final TextAttribute SWAP_COLORS
Attribute key for swapping foreground and background Paints (or Colors).

Values are instances of Boolean. The default is not to swap the foreground and background. If the foreground and background attributes are both defined, this causes them to be swapped when rendering text. If either is defaulted, the exact effect is undefined--generally it will produce an 'inverted' appearance.


SWAP_COLORS_ON

public static final Boolean SWAP_COLORS_ON
Swap foreground and background.
Constructor Detail

TextAttribute

protected TextAttribute(String name)
Constructs a TextAttribute with the specified name.
Parameters:
name - the attribute name to assign to this TextAttribute
Method Detail

readResolve

protected Object readResolve()
                      throws InvalidObjectException
Resolves instances being deserialized to the predefined constants.
Overrides:
readResolve in class AttributedCharacterIterator.Attribute

Java Platform 1.2

Submit a bug or feature Version 1.2 of Java Platform API Specification
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