Serializable
public final class TextAttribute extends AttributedCharacterIterator.Attribute
TextAttribute
class defines attribute keys and attribute values used for text rendering. TextAttribute
instances are used as attribute keys to identify attributes in Font
, TextLayout
, AttributedCharacterIterator
, and other classes handling text attributes. Other constants defined in this class can be used as attribute values.
For each text attribute, the documentation provides:
null
is treated the same as the default value and results in the default behavior. TextAttribute.WEIGHT_BOLD
and Float.valueOf(2.0f)
indicate the same WEIGHT
. Number
(used for WEIGHT
, WIDTH
, POSTURE
, SIZE
, JUSTIFICATION
, and TRACKING
) can vary along their natural range and are not restricted to the predefined constants. Number.floatValue()
is used to get the actual value from the Number
. WEIGHT
, WIDTH
, and POSTURE
are interpolated by the system, which can select the 'nearest available' font or use other techniques to approximate the user's request. Key | Value Type | Principal Constants | Default Value |
---|---|---|---|
FAMILY |
String | See Font DIALOG , DIALOG_INPUT , SERIF , SANS_SERIF , and MONOSPACED . |
"Default" (use platform default) |
WEIGHT |
Number | WEIGHT_REGULAR, WEIGHT_BOLD | WEIGHT_REGULAR |
WIDTH |
Number | WIDTH_CONDENSED, WIDTH_REGULAR, WIDTH_EXTENDED |
WIDTH_REGULAR |
POSTURE |
Number | POSTURE_REGULAR, POSTURE_OBLIQUE | POSTURE_REGULAR |
SIZE |
Number | none | 12.0 |
TRANSFORM |
TransformAttribute |
See TransformAttribute IDENTITY |
TransformAttribute.IDENTITY |
SUPERSCRIPT |
Integer | SUPERSCRIPT_SUPER, SUPERSCRIPT_SUB | 0 (use the standard glyphs and metrics) |
FONT |
Font |
none | null (do not override font resolution) |
CHAR_REPLACEMENT |
GraphicAttribute |
none | null (draw text using font glyphs) |
FOREGROUND |
Paint |
none | null (use current graphics paint) |
BACKGROUND |
Paint |
none | null (do not render background) |
UNDERLINE |
Integer | UNDERLINE_ON | -1 (do not render underline) |
STRIKETHROUGH |
Boolean | STRIKETHROUGH_ON | false (do not render strikethrough) |
RUN_DIRECTION |
Boolean | RUN_DIRECTION_LTR RUN_DIRECTION_RTL |
null (use Bidi standard default) |
BIDI_EMBEDDING |
Integer | none | 0 (use base line direction) |
JUSTIFICATION |
Number | JUSTIFICATION_FULL | JUSTIFICATION_FULL |
INPUT_METHOD_HIGHLIGHT |
InputMethodHighlight , Annotation |
(see class) | null (do not apply input highlighting) |
INPUT_METHOD_UNDERLINE |
Integer | UNDERLINE_LOW_ONE_PIXEL, UNDERLINE_LOW_TWO_PIXEL |
-1 (do not render underline) |
SWAP_COLORS |
Boolean | SWAP_COLORS_ON | false (do not swap colors) |
NUMERIC_SHAPING |
NumericShaper |
none | null (do not shape digits) |
KERNING |
Integer | KERNING_ON | 0 (do not request kerning) |
LIGATURES |
Integer | LIGATURES_ON | 0 (do not form optional ligatures) |
TRACKING |
Number | TRACKING_LOOSE, TRACKING_TIGHT | 0 (do not add tracking) |
Modifier and Type | Field | Description |
---|---|---|
static final TextAttribute |
BACKGROUND |
Attribute key for the paint used to render the background of the text. |
static final TextAttribute |
BIDI_EMBEDDING |
Attribute key for the embedding level of the text. |
static final TextAttribute |
CHAR_REPLACEMENT |
Attribute key for a user-defined glyph to display in lieu of the font's standard glyph for a character. |
static final TextAttribute |
FAMILY |
Attribute key for the font name. |
static final TextAttribute |
FONT |
Attribute key used to provide the font to use to render text. |
static final TextAttribute |
FOREGROUND |
Attribute key for the paint used to render the text. |
static final TextAttribute |
INPUT_METHOD_HIGHLIGHT |
Attribute key for input method highlight styles. |
static final TextAttribute |
INPUT_METHOD_UNDERLINE |
Attribute key for input method underlines. |
static final TextAttribute |
JUSTIFICATION |
Attribute key for the justification of a paragraph. |
static final Float |
JUSTIFICATION_FULL |
Justify the line to the full requested width. |
static final Float |
JUSTIFICATION_NONE |
Do not allow the line to be justified. |
static final TextAttribute |
KERNING |
Attribute key to request kerning. |
static final Integer |
KERNING_ON |
Request standard kerning. |
static final TextAttribute |
LIGATURES |
Attribute key for enabling optional ligatures. |
static final Integer |
LIGATURES_ON |
Request standard optional ligatures. |
static final TextAttribute |
NUMERIC_SHAPING |
Attribute key for converting ASCII decimal digits to other decimal ranges. |
static final TextAttribute |
POSTURE |
Attribute key for the posture of a font. |
static final Float |
POSTURE_OBLIQUE |
The standard italic posture. |
static final Float |
POSTURE_REGULAR |
The standard posture, upright. |
static final TextAttribute |
RUN_DIRECTION |
Attribute key for the run direction of the line. |
static final Boolean |
RUN_DIRECTION_LTR |
Left-to-right run direction. |
static final Boolean |
RUN_DIRECTION_RTL |
Right-to-left run direction. |
static final TextAttribute |
SIZE |
Attribute key for the font size. |
static final TextAttribute |
STRIKETHROUGH |
Attribute key for strikethrough. |
static final Boolean |
STRIKETHROUGH_ON |
A single strikethrough. |
static final TextAttribute |
SUPERSCRIPT |
Attribute key for superscripting and subscripting. |
static final Integer |
SUPERSCRIPT_SUB |
Standard subscript. |
static final Integer |
SUPERSCRIPT_SUPER |
Standard superscript. |
static final TextAttribute |
SWAP_COLORS |
Attribute key for swapping foreground and background Paints . |
static final Boolean |
SWAP_COLORS_ON |
Swap foreground and background. |
static final TextAttribute |
TRACKING |
Attribute key to control tracking. |
static final Float |
TRACKING_LOOSE |
Perform loose tracking. |
static final Float |
TRACKING_TIGHT |
Perform tight tracking. |
static final TextAttribute |
TRANSFORM |
Attribute key for the transform of a font. |
static final TextAttribute |
UNDERLINE |
Attribute key for underline. |
static final Integer |
UNDERLINE_LOW_DASHED |
Single pixel dashed low underline. |
static final Integer |
UNDERLINE_LOW_DOTTED |
Single pixel dotted low underline. |
static final Integer |
UNDERLINE_LOW_GRAY |
Double pixel gray low underline. |
static final Integer |
UNDERLINE_LOW_ONE_PIXEL |
Single pixel solid low underline. |
static final Integer |
UNDERLINE_LOW_TWO_PIXEL |
Double pixel solid low underline. |
static final Integer |
UNDERLINE_ON |
Standard underline. |
static final TextAttribute |
WEIGHT |
Attribute key for the weight of a font. |
static final Float |
WEIGHT_BOLD |
The standard bold weight. |
static final Float |
WEIGHT_DEMIBOLD |
A moderately lighter weight than WEIGHT_BOLD . |
static final Float |
WEIGHT_DEMILIGHT |
An intermediate weight between WEIGHT_LIGHT and WEIGHT_STANDARD . |
static final Float |
WEIGHT_EXTRA_LIGHT |
The lightest predefined weight. |
static final Float |
WEIGHT_EXTRABOLD |
An extra heavy weight. |
static final Float |
WEIGHT_HEAVY |
A moderately heavier weight than WEIGHT_BOLD . |
static final Float |
WEIGHT_LIGHT |
The standard light weight. |
static final Float |
WEIGHT_MEDIUM |
An intermediate weight between WEIGHT_REGULAR and WEIGHT_BOLD . |
static final Float |
WEIGHT_REGULAR |
The standard weight. |
static final Float |
WEIGHT_SEMIBOLD |
A moderately heavier weight than WEIGHT_REGULAR . |
static final Float |
WEIGHT_ULTRABOLD |
The heaviest predefined weight. |
static final TextAttribute |
WIDTH |
Attribute key for the width of a font. |
static final Float |
WIDTH_CONDENSED |
The most condensed predefined width. |
static final Float |
WIDTH_EXTENDED |
The most extended predefined width. |
static final Float |
WIDTH_REGULAR |
The standard width. |
static final Float |
WIDTH_SEMI_CONDENSED |
A moderately condensed width. |
static final Float |
WIDTH_SEMI_EXTENDED |
A moderately extended width. |
INPUT_METHOD_SEGMENT, LANGUAGE, READING
Modifier | Constructor | Description |
---|---|---|
protected |
Constructs a TextAttribute with the specified name. |
Modifier and Type | Method | Description |
---|---|---|
protected Object |
readResolve() |
Resolves instances being deserialized to the predefined constants. |
equals, getName, hashCode, toString
public static final TextAttribute FAMILY
String
. The default value is "Default"
, which causes the platform default font family to be used. The Font
class defines constants for the logical font names DIALOG
, DIALOG_INPUT
, SANS_SERIF
, SERIF
, and MONOSPACED
.
This defines the value passed as name
to the Font
constructor. Both logical and physical font names are allowed. If a font with the requested name is not found, the default font is used.
Note: This attribute is unfortunately misnamed, as it specifies the face name and not just the family. Thus values such as "Lucida Sans Bold" will select that face if it exists. Note, though, that if the requested face does not exist, the default will be used with regular weight. The "Bold" in the name is part of the face name, not a separate request that the font's weight be bold.
public static final TextAttribute WEIGHT
Number
. The default value is WEIGHT_REGULAR
. Several constant values are provided, see WEIGHT_EXTRA_LIGHT
, WEIGHT_LIGHT
, WEIGHT_DEMILIGHT
, WEIGHT_REGULAR
, WEIGHT_SEMIBOLD
, WEIGHT_MEDIUM
, WEIGHT_DEMIBOLD
, WEIGHT_BOLD
, WEIGHT_HEAVY
, WEIGHT_EXTRABOLD
, and WEIGHT_ULTRABOLD
. The value WEIGHT_BOLD
corresponds to the style value Font.BOLD
as passed to the Font
constructor.
The value is roughly the ratio of the stem width to that of the regular weight.
The system can interpolate the provided value.
public static final Float WEIGHT_EXTRA_LIGHT
public static final Float WEIGHT_LIGHT
public static final Float WEIGHT_DEMILIGHT
WEIGHT_LIGHT
and WEIGHT_STANDARD
.public static final Float WEIGHT_REGULAR
WEIGHT
.public static final Float WEIGHT_SEMIBOLD
WEIGHT_REGULAR
.public static final Float WEIGHT_MEDIUM
WEIGHT_REGULAR
and WEIGHT_BOLD
.public static final Float WEIGHT_DEMIBOLD
WEIGHT_BOLD
.public static final Float WEIGHT_BOLD
public static final Float WEIGHT_HEAVY
WEIGHT_BOLD
.public static final Float WEIGHT_EXTRABOLD
public static final Float WEIGHT_ULTRABOLD
public static final TextAttribute WIDTH
Number
. The default value is WIDTH_REGULAR
. Several constant values are provided, see WIDTH_CONDENSED
, WIDTH_SEMI_CONDENSED
, WIDTH_REGULAR
, WIDTH_SEMI_EXTENDED
, WIDTH_EXTENDED
.
The value is roughly the ratio of the advance width to that of the regular width.
The system can interpolate the provided value.
public static final Float WIDTH_CONDENSED
public static final Float WIDTH_SEMI_CONDENSED
public static final Float WIDTH_REGULAR
WIDTH
.public static final Float WIDTH_SEMI_EXTENDED
public static final Float WIDTH_EXTENDED
public static final TextAttribute POSTURE
Number
. The default value is POSTURE_REGULAR
. Two constant values are provided, POSTURE_REGULAR
and POSTURE_OBLIQUE
. The value POSTURE_OBLIQUE
corresponds to the style value Font.ITALIC
as passed to the Font
constructor.
The value is roughly the slope of the stems of the font, expressed as the run over the rise. Positive values lean right.
The system can interpolate the provided value.
This will affect the font's italic angle as returned by Font.getItalicAngle
.
public static final Float POSTURE_REGULAR
POSTURE
.public static final Float POSTURE_OBLIQUE
public static final TextAttribute SIZE
Number
. The default value is 12pt. This corresponds to the size
parameter to the Font
constructor.
Very large or small sizes will impact rendering performance, and the rendering system might not render text at these sizes. Negative sizes are illegal and result in the default 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.
public static final TextAttribute TRANSFORM
TransformAttribute
. The default value is TransformAttribute.IDENTITY
. The TransformAttribute
class defines the constant IDENTITY
.
This corresponds to the transform passed to Font.deriveFont(AffineTransform)
. Since that transform is mutable and TextAttribute
values must not be, the TransformAttribute
wrapper class is used.
The primary intent is to support scaling and skewing, though other effects are possible.
Some transforms will cause the baseline to be rotated and/or shifted. The text and the baseline are transformed together so that the text follows the new baseline. For example, with text on a horizontal baseline, the new baseline follows the direction of the unit x vector passed through the transform. Text metrics are measured against this new baseline. So, for example, with other things being equal, text rendered with a rotated TRANSFORM and an unrotated TRANSFORM will measure as having the same ascent, descent, and advance.
In styled text, the baselines for each such run are aligned one after the other to potentially create a non-linear baseline for the entire run of text. For more information, see TextLayout.getLayoutPath()
.
public static final TextAttribute SUPERSCRIPT
Integer
. The default value is 0, which means that no superscript or subscript is used. Two constant values are provided, see SUPERSCRIPT_SUPER
and SUPERSCRIPT_SUB
. These have the values 1 and -1 respectively. Values of greater magnitude define greater levels of superscript or subscripting, for example, 2 corresponds to super-superscript, 3 to super-super-superscript, and similarly for negative values and subscript, up to a level of 7 (or -7). Values beyond this range are reserved; behavior is platform-dependent.
SUPERSCRIPT
can impact the ascent and descent of a font. The ascent and descent can never become negative, however.
public static final Integer SUPERSCRIPT_SUPER
public static final Integer SUPERSCRIPT_SUB
public static final TextAttribute FONT
Font
. The default value is null, indicating that normal resolution of a Font
from attributes should be performed. TextLayout
and AttributedCharacterIterator
work in terms of Maps
of TextAttributes
. Normally, all the attributes are examined and used to select and configure a Font
instance. If a FONT
attribute is present, though, its associated Font
will be used. This provides 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.
FONT
is used for special situations where clients already have a Font
instance but still need to use Map
-based APIs. Typically, there will be no other attributes in the Map
except the FONT
attribute. With Map
-based APIs the common case is to specify all attributes individually, so FONT
is not needed or desirable.
However, if both FONT
and other attributes are present in the Map
, the rendering system will merge the attributes defined in the Font
with the additional attributes. This merging process classifies TextAttributes
into two groups. One group, the 'primary' group, is considered fundamental to the selection and metric behavior of a font. These attributes are FAMILY
, WEIGHT
, WIDTH
, POSTURE
, SIZE
, TRANSFORM
, SUPERSCRIPT
, and TRACKING
. The other group, the 'secondary' group, consists of all other defined attributes, with the exception of FONT
itself.
To generate the new Map
, first the Font
is obtained from the FONT
attribute, and all of its attributes extracted into a new Map
. Then only the secondary attributes from the original Map
are added to those in the new Map
. Thus the values of primary attributes come solely from the Font
, and the values of secondary attributes originate with the Font
but can be overridden by other values in the Map
.
Note:Font's Map
-based constructor and deriveFont
methods do not process the FONT
attribute, as these are used to create new Font
objects. Instead, Font.getFont(Map)
should be used to handle the FONT
attribute.
public static final TextAttribute CHAR_REPLACEMENT
This attribute is used to reserve space for a graphic or other component embedded in a line of text. It is required for correct positioning of 'inline' components within a line when bidirectional reordering (see Bidi
) is performed. Each character (Unicode code point) will be rendered using the provided GraphicAttribute. Typically, the characters to which this attribute is applied should be \uFFFC
.
The GraphicAttribute determines the logical and visual bounds of the text; the actual Font values are ignored.
public static final TextAttribute FOREGROUND
Paint
. The default value is null, indicating that the Paint
set on the Graphics2D
at the time of rendering is used. Glyphs will be rendered using this Paint
regardless of the Paint
value set on the Graphics
(but see SWAP_COLORS
).
public static final TextAttribute BACKGROUND
Paint
. The default value is null, indicating that the background should not be rendered. The logical bounds of the text will be filled using this Paint
, and then the text will be rendered on top of it (but see SWAP_COLORS
).
The visual bounds of the text is extended to include the logical bounds, if necessary. The outline is not affected.
public static final TextAttribute UNDERLINE
Integer
. The default value is -1, which means no underline. The constant value UNDERLINE_ON
is provided.
The underline affects both the visual bounds and the outline of the text.
public static final Integer UNDERLINE_ON
public static final TextAttribute STRIKETHROUGH
Boolean
. The default value is false
, which means no strikethrough. The constant value STRIKETHROUGH_ON
is provided.
The strikethrough affects both the visual bounds and the outline of the text.
public static final Boolean STRIKETHROUGH_ON
public static final TextAttribute RUN_DIRECTION
Boolean
. The default value is null, which indicates that the standard Bidi algorithm for determining run direction should be used with the value Bidi.DIRECTION_DEFAULT_LEFT_TO_RIGHT
. The constants RUN_DIRECTION_RTL
and RUN_DIRECTION_LTR
are provided.
This determines the value passed to the Bidi
constructor to select the primary direction of the text in the paragraph.
Note: This attribute should have the same value for all the text in a paragraph, otherwise the behavior is undetermined.
public static final Boolean RUN_DIRECTION_LTR
public static final Boolean RUN_DIRECTION_RTL
public static final TextAttribute BIDI_EMBEDDING
Integer
. The default value is null
, indicating that the Bidirectional algorithm should run without explicit embeddings. Positive values 1 through 61 are embedding levels, negative values -1 through -61 are override levels. The value 0 means that the base line direction is used. These levels are passed in the embedding levels array to the Bidi
constructor.
Note: When this attribute is present anywhere in a paragraph, then any Unicode bidi control characters (RLO, LRO, RLE, LRE, and PDF) in the paragraph are disregarded, and runs of text where this attribute is not present are treated as though it were present and had the value 0.
public static final TextAttribute JUSTIFICATION
Number
. The default value is 1, indicating that justification should use the full width provided. Values are pinned to the range [0..1]. The constants JUSTIFICATION_FULL
and JUSTIFICATION_NONE
are provided.
Specifies the fraction of the extra space to use when justification is requested on a TextLayout
. For example, if the line is 50 points wide and it is requested to justify to 70 points, a value of 0.75 will pad to use three-quarters of the remaining space, or 15 points, so that the resulting line will be 65 points in length.
Note: This should have the same value for all the text in a paragraph, otherwise the behavior is undetermined.
public static final Float JUSTIFICATION_FULL
JUSTIFICATION
.public static final Float JUSTIFICATION_NONE
public static final TextAttribute INPUT_METHOD_HIGHLIGHT
Values are instances of InputMethodHighlight
or Annotation
. The default value is null
, which means that input method styles should not be applied before rendering.
If adjacent runs of text with the same InputMethodHighlight
need to be rendered separately, the InputMethodHighlights
should be wrapped in Annotation
instances.
Input method highlights are used while text is being composed by 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.
public static final TextAttribute INPUT_METHOD_UNDERLINE
Integer
. The default value is -1
, which means no underline. Several constant values are provided, see UNDERLINE_LOW_ONE_PIXEL
, UNDERLINE_LOW_TWO_PIXEL
, UNDERLINE_LOW_DOTTED
, UNDERLINE_LOW_GRAY
, and UNDERLINE_LOW_DASHED
.
This may be used in conjunction with UNDERLINE
if desired. The primary purpose is for use by input methods. Other use of these underlines for simple ornamentation might confuse users.
The input method underline affects both the visual bounds and the outline of the text.
public static final Integer UNDERLINE_LOW_ONE_PIXEL
public static final Integer UNDERLINE_LOW_TWO_PIXEL
public static final Integer UNDERLINE_LOW_DOTTED
public static final Integer UNDERLINE_LOW_GRAY
public static final Integer UNDERLINE_LOW_DASHED
public static final TextAttribute SWAP_COLORS
Paints
. Values are instances of Boolean
. The default value is false
, which means do not swap colors. The constant value SWAP_COLORS_ON
is defined.
If the FOREGROUND
attribute is set, its Paint
will be used as the background, otherwise the Paint
currently on the Graphics
will be used. If the BACKGROUND
attribute is set, its Paint
will be used as the foreground, otherwise the system will find a contrasting color to the (resolved) background so that the text will be visible.
public static final Boolean SWAP_COLORS_ON
public static final TextAttribute NUMERIC_SHAPING
NumericShaper
. The default is null
, which means do not perform numeric shaping. When a numeric shaper is defined, the text is first processed by the shaper before any other analysis of the text is performed.
Note: This should have the same value for all the text in the paragraph, otherwise the behavior is undetermined.
public static final TextAttribute KERNING
Integer
. The default value is 0
, which does not request kerning. The constant value KERNING_ON
is provided.
The default advances of single characters are not appropriate for some character sequences, for example "To" or "AWAY". Without kerning the adjacent characters appear to be separated by too much space. Kerning causes selected sequences of characters to be spaced differently for a more pleasing visual appearance.
public static final Integer KERNING_ON
public static final TextAttribute LIGATURES
Integer
. The default value is 0
, which means do not use optional ligatures. The constant value LIGATURES_ON
is defined.
Ligatures required by the writing system are always enabled.
public static final Integer LIGATURES_ON
public static final TextAttribute TRACKING
Number
. The default value is 0
, which means no additional tracking. The constant values TRACKING_TIGHT
and TRACKING_LOOSE
are provided.
The tracking value is multiplied by the font point size and passed through the font transform to determine an additional amount to add to the advance of each glyph cluster. Positive tracking values will inhibit formation of optional ligatures. Tracking values are typically between -0.1
and 0.3
; values outside this range are generally not desirable.
public static final Float TRACKING_TIGHT
public static final Float TRACKING_LOOSE
protected TextAttribute(String name)
TextAttribute
with the specified name.name
- the attribute name to assign to this TextAttribute
protected Object readResolve() throws InvalidObjectException
readResolve
in class AttributedCharacterIterator.Attribute
Attribute
objectInvalidObjectException
- if the object to resolve is not an instance of Attribute
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Licensed under the GNU General Public License, version 2, with the Classpath Exception.
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