java.awt
Class Color

java.lang.Object
  java.awt.Color

All Implemented Interfaces:

Paint, Serializable, Transparency

Direct Known Subclasses:

ColorUIResource, SystemColor

public class Color

extends Object

implements Paint, Serializable

The Color class is used encapsulate colors in the default sRGB color space or colors in arbitrary color spaces identified by a ColorSpace. Every color has an implicit alpha value of 1.0 or an explicit one provided in the constructor. The alpha value defines the transparency of a color and can be represented by a float value in the range 0.0 - 1.0 or 0 - 255. An alpha value of 1.0 or 255 means that the color is completely opaque and an alpha value of 0 or 0.0 means that the color is completely transparent. When constructing a Color with an explicit alpha or getting the color/alpha components of a Color, the color components are never premultiplied by the alpha component.

The default color space for the Java 2D(tm) API is sRGB, a proposed standard RGB color space. For further information on sRGB, see http://www.w3.org/pub/WWW/Graphics/Color/sRGB.html .

Author:

Sami Shaio, Arthur van Hoff

See Also:

ColorSpace, AlphaComposite, Serialized Form

Field Summary

static Color	black The color black.
static Color	BLACK The color black.
static Color	blue The color blue.
static Color	BLUE The color blue.
private ColorSpace	cs The ColorSpace.
static Color	cyan The color cyan.
static Color	CYAN The color cyan.
static Color	DARK_GRAY The color dark gray.
static Color	darkGray The color dark gray.
private static double	FACTOR
private float	falpha The alpha value as a float component.
private float[]	frgbvalue The color value in the default sRGB ColorSpace as float components (no alpha).
private float[]	fvalue The color value in the native ColorSpace as float components (no alpha).
static Color	gray The color gray.
static Color	GRAY The color gray.
static Color	green The color green.
static Color	GREEN The color green.
static Color	LIGHT_GRAY The color light gray.
static Color	lightGray The color light gray.
static Color	magenta The color magenta.
static Color	MAGENTA The color magenta.
static Color	orange The color orange.
static Color	ORANGE The color orange.
private long	pData Private data.
static Color	pink The color pink.
static Color	PINK The color pink.
static Color	red The color red.
static Color	RED The color red.
private static long	serialVersionUID
private PaintContext	theContext The paint context used to generate a solid color pattern.
(package private) int	value The color value.
static Color	white The color white.
static Color	WHITE The color white.
static Color	yellow The color yellow.
static Color	YELLOW The color yellow.

Fields inherited from interface java.awt.Transparency

BITMASK, OPAQUE, TRANSLUCENT

Constructor Summary

Color(ColorSpace cspace, float[] components, float alpha)
Creates a color in the specified ColorSpace with the color components specified in the float array and the specified alpha.

Color(float r, float g, float b)
Creates an opaque sRGB color with the specified red, green, and blue values in the range (0.0 - 1.0).

Color(float r, float g, float b, float a)
Creates an sRGB color with the specified red, green, blue, and alpha values in the range (0.0 - 1.0).

Color(int rgb)
Creates an opaque sRGB color with the specified combined RGB value consisting of the red component in bits 16-23, the green component in bits 8-15, and the blue component in bits 0-7.

Color(int rgba, boolean hasalpha)
Creates an sRGB color with the specified combined RGBA value consisting of the alpha component in bits 24-31, the red component in bits 16-23, the green component in bits 8-15, and the blue component in bits 0-7.

Color(int r, int g, int b)
Creates an opaque sRGB color with the specified red, green, and blue values in the range (0 - 255).

Color(int r, int g, int b, int a)
Creates an sRGB color with the specified red, green, blue, and alpha values in the range (0 - 255).

Method Summary

Color	brighter() Creates a new Color that is a brighter version of this Color.
PaintContext	createContext(ColorModel cm, Rectangle r, Rectangle2D r2d, AffineTransform xform, RenderingHints hints) Creates and returns a PaintContext used to generate a solid color pattern.
Color	darker() Creates a new Color that is a darker version of this Color.
static Color	decode(String nm) Converts a String to an integer and returns the specified opaque Color.
boolean	equals(Object obj) Determines whether another object is equal to this Color.
int	getAlpha() Returns the alpha component in the range 0-255.
int	getBlue() Returns the blue component in the range 0-255 in the default sRGB space.
static Color	getColor(String nm) Finds a color in the system properties.
static Color	getColor(String nm, Color v) Finds a color in the system properties.
static Color	getColor(String nm, int v) Finds a color in the system properties.
float[]	getColorComponents(ColorSpace cspace, float[] compArray) Returns a float array containing only the color components of the Color in the ColorSpace specified by the cspace parameter.
float[]	getColorComponents(float[] compArray) Returns a float array containing only the color components of the Color, in the ColorSpace of the Color.
ColorSpace	getColorSpace() Returns the ColorSpace of this Color.
float[]	getComponents(ColorSpace cspace, float[] compArray) Returns a float array containing the color and alpha components of the Color, in the ColorSpace specified by the cspace parameter.
float[]	getComponents(float[] compArray) Returns a float array containing the color and alpha components of the Color, in the ColorSpace of the Color.
int	getGreen() Returns the green component in the range 0-255 in the default sRGB space.
static Color	getHSBColor(float h, float s, float b) Creates a Color object based on the specified values for the HSB color model.
int	getRed() Returns the red component in the range 0-255 in the default sRGB space.
int	getRGB() Returns the RGB value representing the color in the default sRGB ColorModel.
float[]	getRGBColorComponents(float[] compArray) Returns a float array containing only the color components of the Color, in the default sRGB color space.
float[]	getRGBComponents(float[] compArray) Returns a float array containing the color and alpha components of the Color, as represented in the default sRGB color space.
int	getTransparency() Returns the transparency mode for this Color.
int	hashCode() Computes the hash code for this Color.
static int	HSBtoRGB(float hue, float saturation, float brightness) Converts the components of a color, as specified by the HSB model, to an equivalent set of values for the default RGB model.
private static void	initIDs() Initialize JNI field and method IDs
static float[]	RGBtoHSB(int r, int g, int b, float[] hsbvals) Converts the components of a color, as specified by the default RGB model, to an equivalent set of values for hue, saturation, and brightness that are the three components of the HSB model.
private static void	testColorValueRange(float r, float g, float b, float a) Checks the color float components supplied for validity.
private static void	testColorValueRange(int r, int g, int b, int a) Checks the color integer components supplied for validity.
String	toString() Returns a string representation of this Color.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

white

public static final Color white

The color white. In the default sRGB space.

WHITE

public static final Color WHITE

The color white. In the default sRGB space.

lightGray

public static final Color lightGray

The color light gray. In the default sRGB space.

LIGHT_GRAY

public static final Color LIGHT_GRAY

The color light gray. In the default sRGB space.

gray

public static final Color gray

The color gray. In the default sRGB space.

GRAY

public static final Color GRAY

The color gray. In the default sRGB space.

darkGray

public static final Color darkGray

The color dark gray. In the default sRGB space.

DARK_GRAY

public static final Color DARK_GRAY

The color dark gray. In the default sRGB space.

black

public static final Color black

The color black. In the default sRGB space.

BLACK

public static final Color BLACK

The color black. In the default sRGB space.

red

public static final Color red

The color red. In the default sRGB space.

RED

public static final Color RED

The color red. In the default sRGB space.

pink

public static final Color pink

The color pink. In the default sRGB space.

PINK

public static final Color PINK

The color pink. In the default sRGB space.

orange

public static final Color orange

The color orange. In the default sRGB space.

ORANGE

public static final Color ORANGE

The color orange. In the default sRGB space.

yellow

public static final Color yellow

The color yellow. In the default sRGB space.

YELLOW

public static final Color YELLOW

The color yellow. In the default sRGB space.

green

public static final Color green

The color green. In the default sRGB space.

GREEN

public static final Color GREEN

The color green. In the default sRGB space.

magenta

public static final Color magenta

The color magenta. In the default sRGB space.

MAGENTA

public static final Color MAGENTA

The color magenta. In the default sRGB space.

cyan

public static final Color cyan

The color cyan. In the default sRGB space.

CYAN

public static final Color CYAN

The color cyan. In the default sRGB space.

blue

public static final Color blue

The color blue. In the default sRGB space.

BLUE

public static final Color BLUE

The color blue. In the default sRGB space.

pData

private transient long pData

Private data.

value

int value

The color value.

See Also:

getRGB()

frgbvalue

private float[] frgbvalue

The color value in the default sRGB ColorSpace as float components (no alpha). If null after object construction, this must be an sRGB color constructed with 8-bit precision, so compute from the int color value.

See Also:

getRGBColorComponents(float[]), getRGBComponents(float[])

fvalue

private float[] fvalue

The color value in the native ColorSpace as float components (no alpha). If null after object construction, this must be an sRGB color constructed with 8-bit precision, so compute from the int color value.

See Also:

getRGBColorComponents(float[]), getRGBComponents(float[])

falpha

private float falpha

The alpha value as a float component. If frgbvalue is null, this is not valid data, so compute from the int color value.

See Also:

getRGBComponents(float[]), getComponents(float[])

cs

private ColorSpace cs

The ColorSpace. If null, then it's default is sRGB.

See Also:

getColor(java.lang.String), getColorSpace(), getColorComponents(float[])

serialVersionUID

private static final long serialVersionUID

See Also:

Constant Field Values

FACTOR

private static final double FACTOR

See Also:

Constant Field Values

theContext

private transient PaintContext theContext

The paint context used to generate a solid color pattern.

See Also:

createContext()

Constructor Detail

Color

public Color(int r,
             int g,
             int b)

Creates an opaque sRGB color with the specified red, green, and blue values in the range (0 - 255). The actual color used in rendering depends on finding the best match given the color space available for a given output device. Alpha is defaulted to 255.

Parameters:

r - the red component

g - the green component

b - the blue component

See Also:

getRed(), getGreen(), getBlue(), getRGB()

Color

public Color(int r,
             int g,
             int b,
             int a)

Creates an sRGB color with the specified red, green, blue, and alpha values in the range (0 - 255).

Parameters:

r - the red component

g - the green component

b - the blue component

a - the alpha component

See Also:

getRed(), getGreen(), getBlue(), getAlpha(), getRGB()

Color

public Color(int rgb)

Creates an opaque sRGB color with the specified combined RGB value consisting of the red component in bits 16-23, the green component in bits 8-15, and the blue component in bits 0-7. The actual color used in rendering depends on finding the best match given the color space available for a particular output device. Alpha is defaulted to 255.

Parameters:

rgb - the combined RGB components

See Also:

ColorModel.getRGBdefault(), getRed(), getGreen(), getBlue(), getRGB()

Color

public Color(int rgba,
             boolean hasalpha)

Creates an sRGB color with the specified combined RGBA value consisting of the alpha component in bits 24-31, the red component in bits 16-23, the green component in bits 8-15, and the blue component in bits 0-7. If the hasalpha argument is false, alpha is defaulted to 255.

Parameters:

rgba - the combined RGBA components

hasalpha - true if the alpha bits are valid; false otherwise

See Also:

ColorModel.getRGBdefault(), getRed(), getGreen(), getBlue(), getAlpha(), getRGB()

Color

public Color(float r,
             float g,
             float b)

Creates an opaque sRGB color with the specified red, green, and blue values in the range (0.0 - 1.0). Alpha is defaulted to 1.0. The actual color used in rendering depends on finding the best match given the color space available for a particular output device.

Parameters:

r - the red component

g - the green component

b - the blue component

See Also:

getRed(), getGreen(), getBlue(), getRGB()

Color

public Color(float r,
             float g,
             float b,
             float a)

Creates an sRGB color with the specified red, green, blue, and alpha values in the range (0.0 - 1.0). The actual color used in rendering depends on finding the best match given the color space available for a particular output device.

Parameters:

r - the red component

g - the green component

b - the blue component

a - the alpha component

See Also:

getRed(), getGreen(), getBlue(), getAlpha(), getRGB()

Color

public Color(ColorSpace cspace,
             float[] components,
             float alpha)

Creates a color in the specified ColorSpace with the color components specified in the float array and the specified alpha. The number of components is determined by the type of the ColorSpace. For example, RGB requires 3 components, but CMYK requires 4 components.

Parameters:

cspace - the ColorSpace to be used to interpret the components

components - an arbitrary number of color components that is compatible with the

alpha - alpha value

Throws:

IllegalArgumentException - if any of the values in the components array or alpha is outside of the range 0.0 to 1.0

See Also:

getComponents(float[]), getColorComponents(float[])

Method Detail

initIDs

private static void initIDs()

Initialize JNI field and method IDs

testColorValueRange

private static void testColorValueRange(int r,
                                        int g,
                                        int b,
                                        int a)

Checks the color integer components supplied for validity. Throws an IllegalArgumentException if the value is out of range.

Parameters:

r - the Red component

g - the Green component

b - the Blue component

testColorValueRange

private static void testColorValueRange(float r,
                                        float g,
                                        float b,
                                        float a)

Checks the color float components supplied for validity. Throws an IllegalArgumentException if the value is out of range.

Parameters:

r - the Red component

g - the Green component

b - the Blue component

getRed

public int getRed()

Returns the red component in the range 0-255 in the default sRGB space.

Returns:

the red component.

See Also:

getRGB()

getGreen

public int getGreen()

Returns the green component in the range 0-255 in the default sRGB space.

Returns:

the green component.

See Also:

getRGB()

getBlue

public int getBlue()

Returns the blue component in the range 0-255 in the default sRGB space.

Returns:

the blue component.

See Also:

getRGB()

getAlpha

public int getAlpha()

Returns the alpha component in the range 0-255.

Returns:

the alpha component.

See Also:

getRGB()

getRGB

public int getRGB()

Returns the RGB value representing the color in the default sRGB ColorModel. (Bits 24-31 are alpha, 16-23 are red, 8-15 are green, 0-7 are blue).

Returns:

the RGB value of the color in the default sRGB ColorModel.

Since:

JDK1.0

See Also:

ColorModel.getRGBdefault(), getRed(), getGreen(), getBlue()

brighter

public Color brighter()

Creates a new Color that is a brighter version of this Color.

This method applies an arbitrary scale factor to each of the three RGB components of this Color to create a brighter version of this Color. Although brighter and darker are inverse operations, the results of a series of invocations of these two methods might be inconsistent because of rounding errors.

Returns:

a new Color object that is a brighter version of this Color.

Since:

JDK1.0

See Also:

darker()

darker

public Color darker()

Creates a new Color that is a darker version of this Color.

This method applies an arbitrary scale factor to each of the three RGB components of this Color to create a darker version of this Color. Although brighter and darker are inverse operations, the results of a series of invocations of these two methods might be inconsistent because of rounding errors.

Returns:

a new Color object that is a darker version of this Color.

Since:

JDK1.0

See Also:

brighter()

hashCode

public int hashCode()

Computes the hash code for this Color.

Overrides:

hashCode in class Object

Returns:

a hash code value for this object.

Since:

JDK1.0

See Also:

Object.equals(java.lang.Object), Hashtable

equals

public boolean equals(Object obj)

Determines whether another object is equal to this Color.

The result is true if and only if the argument is not null and is a Color object that has the same red, green, blue, and alpha values as this object.

Overrides:

equals in class Object

Parameters:

obj - the object to test for equality with this Color

Returns:

true if the objects are the same; false otherwise.

Since:

JDK1.0

See Also:

Object.hashCode(), Hashtable

toString

public String toString()

Returns a string representation of this Color. This method is intended to be used only for debugging purposes. The content and format of the returned string might vary between implementations. The returned string might be empty but cannot be null.

Overrides:

toString in class Object

Returns:

a string representation of this Color.

decode

public static Color decode(String nm)
                    throws NumberFormatException

Converts a String to an integer and returns the specified opaque Color. This method handles string formats that are used to represent octal and hexidecimal numbers.

Parameters:

nm - a String that represents an opaque color as a 24-bit integer

Returns:

the new Color object.

Throws:

NumberFormatException - if the specified string cannot be interpreted as a decimal, octal, or hexidecimal integer.

Since:

JDK1.1

See Also:

Integer.decode(java.lang.String)

getColor

public static Color getColor(String nm)

Finds a color in the system properties.

The argument is treated as the name of a system property to be obtained. The string value of this property is then interpreted as an integer which is then converted to a Color object.

If the specified property is not found or could not be parsed as an integer then null is returned.

Parameters:

nm - the name of the color property

Returns:

the Color converted from the system property.

Since:

JDK1.0

See Also:

System.getProperty(java.lang.String), Integer.getInteger(java.lang.String), Color(int)

getColor

public static Color getColor(String nm,
                             Color v)

Finds a color in the system properties.

The first argument is treated as the name of a system property to be obtained. The string value of this property is then interpreted as an integer which is then converted to a Color object.

If the specified property is not found or cannot be parsed as an integer then the Color specified by the second argument is returned instead.

Parameters:

nm - the name of the color property

v - the default Color

Returns:

the Color converted from the system property, or the specified Color.

Since:

JDK1.0

See Also:

System.getProperty(java.lang.String), Integer.getInteger(java.lang.String), Color(int)

getColor

public static Color getColor(String nm,
                             int v)

Finds a color in the system properties.

The first argument is treated as the name of a system property to be obtained. The string value of this property is then interpreted as an integer which is then converted to a Color object.

If the specified property is not found or could not be parsed as an integer then the integer value v is used instead, and is converted to a Color object.

Parameters:

nm - the name of the color property

v - the default color value, as an integer

Returns:

the Color converted from the system property or the Color converted from the specified integer.

Since:

JDK1.0

See Also:

System.getProperty(java.lang.String), Integer.getInteger(java.lang.String), Color(int)

HSBtoRGB

public static int HSBtoRGB(float hue,
                           float saturation,
                           float brightness)

Converts the components of a color, as specified by the HSB model, to an equivalent set of values for the default RGB model.

The saturation and brightness components should be floating-point values between zero and one (numbers in the range 0.0-1.0). The hue component can be any floating-point number. The floor of this number is subtracted from it to create a fraction between 0 and 1. This fractional number is then multiplied by 360 to produce the hue angle in the HSB color model.

The integer that is returned by HSBtoRGB encodes the value of a color in bits 0-23 of an integer value that is the same format used by the method getRGB. This integer can be supplied as an argument to the Color constructor that takes a single integer argument.

Parameters:

hue - the hue component of the color

saturation - the saturation of the color

brightness - the brightness of the color

Returns:

the RGB value of the color with the indicated hue, saturation, and brightness.

Since:

JDK1.0

See Also:

getRGB(), Color(int), ColorModel.getRGBdefault()

RGBtoHSB

public static float[] RGBtoHSB(int r,
                               int g,
                               int b,
                               float[] hsbvals)

Converts the components of a color, as specified by the default RGB model, to an equivalent set of values for hue, saturation, and brightness that are the three components of the HSB model.

If the hsbvals argument is null, then a new array is allocated to return the result. Otherwise, the method returns the array hsbvals, with the values put into that array.

Parameters:

r - the red component of the color

g - the green component of the color

b - the blue component of the color

hsbvals - the array used to return the three HSB values, or null

Returns:

an array of three elements containing the hue, saturation, and brightness (in that order), of the color with the indicated red, green, and blue components.

Since:

JDK1.0

See Also:

getRGB(), Color(int), ColorModel.getRGBdefault()

getHSBColor

public static Color getHSBColor(float h,
                                float s,
                                float b)

Creates a Color object based on the specified values for the HSB color model.

The s and b components should be floating-point values between zero and one (numbers in the range 0.0-1.0). The h component can be any floating-point number. The floor of this number is subtracted from it to create a fraction between 0 and 1. This fractional number is then multiplied by 360 to produce the hue angle in the HSB color model.

Parameters:

h - the hue component

s - the saturation of the color

b - the brightness of the color

Returns:

a Color object with the specified hue, saturation, and brightness.

Since:

JDK1.0

getRGBComponents

public float[] getRGBComponents(float[] compArray)

Returns a float array containing the color and alpha components of the Color, as represented in the default sRGB color space. If compArray is null, an array of length 4 is created for the return value. Otherwise, compArray must have length 4 or greater, and it is filled in with the components and returned.

Parameters:

compArray - an array that this method fills with color and alpha components and returns

Returns:

the RGBA components in a float array.

getRGBColorComponents

public float[] getRGBColorComponents(float[] compArray)

Returns a float array containing only the color components of the Color, in the default sRGB color space. If compArray is null, an array of length 3 is created for the return value. Otherwise, compArray must have length 3 or greater, and it is filled in with the components and returned.

Parameters:

compArray - an array that this method fills with color components and returns

Returns:

the RGB components in a float array.

getComponents

public float[] getComponents(float[] compArray)

Returns a float array containing the color and alpha components of the Color, in the ColorSpace of the Color. If compArray is null, an array with length equal to the number of components in the associated ColorSpace plus one is created for the return value. Otherwise, compArray must have at least this length and it is filled in with the components and returned.

Parameters:

compArray - an array that this method fills with the color and alpha components of this Color in its ColorSpace and returns

Returns:

the color and alpha components in a float array.

getColorComponents

public float[] getColorComponents(float[] compArray)

Returns a float array containing only the color components of the Color, in the ColorSpace of the Color. If compArray is null, an array with length equal to the number of components in the associated ColorSpace is created for the return value. Otherwise, compArray must have at least this length and it is filled in with the components and returned.

Parameters:

compArray - an array that this method fills with the color components of this Color in its ColorSpace and returns

Returns:

the color components in a float array.

getComponents

public float[] getComponents(ColorSpace cspace,
                             float[] compArray)

Returns a float array containing the color and alpha components of the Color, in the ColorSpace specified by the cspace parameter. If compArray is null, an array with length equal to the number of components in cspace plus one is created for the return value. Otherwise, compArray must have at least this length, and it is filled in with the components and returned.

Parameters:

cspace - a specified ColorSpace

compArray - an array that this method fills with the color and alpha components of this Color in the specified ColorSpace and returns

Returns:

the color and alpha components in a float array.

getColorComponents

public float[] getColorComponents(ColorSpace cspace,
                                  float[] compArray)

Returns a float array containing only the color components of the Color in the ColorSpace specified by the cspace parameter. If compArray is null, an array with length equal to the number of components in cspace is created for the return value. Otherwise, compArray must have at least this length, and it is filled in with the components and returned.

Parameters:

cspace - a specified ColorSpace

compArray - an array that this method fills with the color components of this Color in the specified ColorSpace

Returns:

the color components in a float array.

getColorSpace

public ColorSpace getColorSpace()

Returns the ColorSpace of this Color.

Returns:

this Color object's ColorSpace.

createContext

public PaintContext createContext(ColorModel cm,
                                  Rectangle r,
                                  Rectangle2D r2d,
                                  AffineTransform xform,
                                  RenderingHints hints)

Creates and returns a PaintContext used to generate a solid color pattern. This enables a Color object to be used as an argument to any method requiring an object implementing the Paint interface. The same PaintContext is returned, regardless of whether or not r, r2d, xform, or hints are null.

Specified by:

createContext in interface Paint

Parameters:

cm - the specified ColorModel

r - the specified Rectangle

r2d - the specified Rectangle2D

xform - the specified AffineTransform

hints - the specified RenderingHints

Returns:

a PaintContext that is used to generate a solid color pattern.

See Also:

Paint, PaintContext, Graphics2D.setPaint(java.awt.Paint)

getTransparency

public int getTransparency()

Returns the transparency mode for this Color. This is required to implement the Paint interface.

Specified by:

getTransparency in interface Transparency

Returns:

this Color object's transparency mode.

See Also:

Paint, Transparency, createContext(java.awt.image.ColorModel, java.awt.Rectangle, java.awt.geom.Rectangle2D, java.awt.geom.AffineTransform, java.awt.RenderingHints)