Java Reference
In-Depth Information
f)
Graphics
is an
abstract
class.
g) The
Font
class inherits directly from class
Graphics
.
13.6
(Concentric Circles Using Method
drawArc
)
Write an application that draws a series of eight
concentric circles. The circles should be separated by 10 pixels. Use
Graphics
method
drawArc
.
13.7
(Concentric Circles Using Class
Ellipse2D.Double
)
Modify your solution to Exercise 13.6
to draw the ovals by using class
Ellipse2D.Double
and method
draw
of class
Graphics2D
.
13.8
(Random Lines Using Class
Line2D.Double
)
Modify your solution to Exercise 13.7 to
draw random lines in random colors and random thicknesses. Use class
Line2D.Double
and method
draw
of class
Graphics2D
to draw the lines.
13.9
(Random Triangles)
Write an application that displays randomly generated triangles in dif-
ferent colors. Each triangle should be filled with a different color. Use class
GeneralPath
and meth-
od
fill
of class
Graphics2D
to draw the triangles.
13.10
(Random Characters)
Write an application that randomly draws characters in different
fonts, sizes and colors.
13.11
(Grid Using Method
drawLine
)
Write an application that draws an 8-by-8 grid. Use
Graphics
method
drawLine
.
13.12
(Grid Using Class
Line2D.Double
)
Modify your solution to Exercise 13.11 to draw the
grid using instances of class
Line2D.Double
and method
draw
of class
Graphics2D
.
13.13
(Grid Using Method
drawRect
)
Write an application that draws a 10-by-10 grid. Use the
Graphics
method
drawRect
.
13.14
(Grid Using Class
Rectangle2D.Double
)
Modify your solution to Exercise 13.13 to draw
the grid by using class
Rectangle2D.Double
and method
draw
of class
Graphics2D
.
13.15
(Drawing Tetrahedrons)
Write an application that draws a tetrahedron (a three-dimension-
al shape with four triangular faces). Use class
GeneralPath
and method
draw
of class
Graphics2D
.
13.16
(Drawing Cubes)
Write an application that draws a cube. Use class
GeneralPath
and meth-
od
draw
of class
Graphics2D
.
13.17
(Circles Using Class
Ellipse2D.Double
)
Write an application that asks the user to input
the radius of a circle as a floating-point number and draws the circle, as well as the values of the
circle's diameter, circumference and area. Use the value 3.14159 for
π
. [
Note:
You may also use the
predefined constant
Math.PI
for the value of
. This constant is more precise than the value
3.14159. Class
Math
is declared in the
java.lang
package, so you need not
import
it.] Use the fol-
lowing formulas (
r
is the radius):
diameter
=
2
r
circumference
=
2
π
π
r
π
r
2
The user should also be prompted for a set of coordinates in addition to the radius. Then draw the
circle and display its diameter, circumference and area, using an
Ellipse2D.Double
object to repre-
sent the circle and method
draw
of class
Graphics2D
to display it.
13.18
(Screen Saver)
Write an application that simulates a screen saver. The application should
randomly draw lines using method
drawLine
of class
Graphics
. After drawing 100 lines, the appli-
cation should clear itself and start drawing lines again. To allow the program to draw continuously,
place a call to
repaint
as the last line in method
paintComponent
. Do you notice any problems with
this on your system?
13.19
(Screen Saver Using
Timer
)
Package
javax.swing
contains a class called
Timer
that is capa-
ble of calling method
actionPerformed
of interface
ActionListener
at a fixed time interval (speci-
area
=
