Java Reference
In-Depth Information
42 }
43
44
/** Add circle areas */
sum(CircleWithPrivateDataFields[] circleArray)
pass array of objects
45
public static double
{
46
// Initialize sum
47
double
sum =
0
;
48
49
// Add areas to sum
50
for
(
int
i =
0
; i < circleArray.length; i++)
51 sum += circleArray[i].getArea();
52
53
return
sum;
54 }
55 }
Radius Area
70.577708 15648.941866
44.152266 6124.291736
24.867853 1942.792644
5.680718 101.380949
36.734246 4239.280350
—————————————————————————————————————————————-
The total area of circles is 28056.687544
The program invokes
createCircleArray()
(line 8) to create an array of five circle objects.
Several circle classes were introduced in this chapter. This example uses the
CircleWithPrivateDataFields
class introduced in Section 8.9, Data Field Encapsulation.
The circle radii are randomly generated using the
Math.random()
method (line 21). The
createCircleArray
method returns an array of
CircleWithPrivateDataFields
objects (line 25). The array is passed to the
printCircleArray
method, which displays the
radius and area of each circle and the total area of the circles.
The sum of the circle areas is computed by invoking the
sum
method (line 41), which takes
the array of
CircleWithPrivateDataFields
objects as the argument and returns a
double
value for the total area.
8.27
✓
✓
What is wrong in the following code?
Check
Point
1
public class
Test {
2
public static void
main(String[] args) {
3 java.util.Date[] dates =
new
java.util.Date[
10
];
4 System.out.println(dates[
0
]);
5 System.out.println(dates[
0
].toString());
6 }
7 }
K
EY
T
ERMS
action 296
anonymous object
constructor 296
data field 296
data field encapsulation
305
attribute
296
319
behavior
296
default constructor 303
dot operator (
.
) 304
getter (or accessor)
class
296
client
299
320
