Java Foundation Classes in a Nutshell

Recall the code that we just used to draw the outline of a circle. The draw()

method has to draw the outline of the circle using only the fill() method. If it

simply calls

fill() on the circle, it ends up creating a solid disk, not the outline of

a circle. So instead,

draw() first passes the circle to the createStrokedShape()

method of the BasicStroke object we’ve specified. createStrokedShape() retur ns

a new shape: a circle of radius 105, minus a concentric circle of radius 95. The

interior of this shape is the area between the two circles, a region that always has

a width of 10 units. Now

draw() can call fill() on this stroked shape to draw the

10-unit-wide outline of the original circle. (We’ll discuss the

fill() operation and

the graphics attributes that it uses in the next section.)

Paint

As we’ve just seen, the Java 2D Stroke attribute turns the task of drawing a line

into the task of filling an area. Prior to Java 2D, an area could be filled only with a

solid color, specified by passing a

Color object to the setColor() method of a

Graphics object. In Java 2D, this color attribute has been generalized to a paint

attribute: you pass a

Paint object to the setPaint() method of a Graphics2D

object. The specified Paint object is used to generate the pixel values used to fill

ar eas.

The most common way to fill an area, however, is still to use a solid color. So

another change in Java 2D is that the

java.awt.Color ...