COLOR METHODS

The Color class defines several methods that help manipulate colors. They are
examined here.
Using Hue, Saturation, and Brightness
The hue-saturation-brightness (HSB) color model is an alternative to red-green-blue
(RGB) for specifying particular colors. Figuratively, hue is a wheel of color. The hue is
specified with a number between 0.0 and 1.0 (the colors are approximately: red, orange,
yellow, green, blue, indigo, and violet). Saturation is another scale ranging from 0.0 to
1.0, representing light pastels to intense hues. Brightness values also range from 0.0 to
1.0, where 1 is bright white and 0 is black. Color supplies two methods that let you
convert between RGB and HSB. They are shown here:
static int HSBtoRGB(float hue, float saturation, float brightness)
static float[ ] RGBtoHSB(int red, int green, int blue, float values[ ])
HSBtoRGB( ) returns a packed RGB value compatible with the Color(int) constructor.
RGBtoHSB( ) returns a float array of HSB values corresponding to RGB integers. If
values is not null, then this array is given the HSB values and returned. Otherwise, a
new array is created and the HSB values are returned in it. In either case, the array
contains the hue at index 0, saturation at index 1, and brightness at index 2.
getRed( ), getGreen( ), getBlue( )
You can obtain the red, green, and blue components of a color independently using
getRed( ), getGreen( ), and getBlue( ), shown here:
int getRed( )
int getGreen( )
int getBlue( )

Each of these methods returns the RGB color component found in the invoking Color
object in the lower 8 bits of an integer.
getRGB( )
To obtain a packed, RGB representation of a color, use getRGB( ), shown here:
int getRGB( )
The return value is organized as described earlier.
Setting the Current Graphics Color
By default, graphics objects are drawn in the current foreground color. You can change
this color by calling the Graphics method setColor( ):
void setColor(Color newColor)
Here, newColor specifies the new drawing color.
You can obtain the current color by calling getColor( ), shown here:
Color getColor( )
A Color Demonstration Applet
The following applet constructs several colors and draws various objects using
these colors:
// Demonstrate color.
import java.awt.*;
import java.applet.*;
/*


*/
public class ColorDemo extends Applet {
// draw lines
public void paint(Graphics g) {
Color c1 = new Color(255, 100, 100);
Color c2 = new Color(100, 255, 100);
Color c3 = new Color(100, 100, 255);
g.setColor(c1);
g.drawLine(0, 0, 100, 100);

g.drawLine(0, 100, 100, 0);
g.setColor(c2);
g.drawLine(40, 25, 250, 180);
g.drawLine(75, 90, 400, 400);
g.setColor(c3);
g.drawLine(20, 150, 400, 40);
g.drawLine(5, 290, 80, 19);
g.setColor(Color.red);
g.drawOval(10, 10, 50, 50);
g.fillOval(70, 90, 140, 100);
g.setColor(Color.blue);
g.drawOval(190, 10, 90, 30);
g.drawRect(10, 10, 60, 50);
g.setColor(Color.cyan);
g.fillRect(100, 10, 60, 50);
g.drawRoundRect(190, 10, 60, 50, 15, 15);
}
}