Java Reference
In-Depth Information
double
arguments as the caller passes. The output shows that each call to method
average
returns the correct value.
Common Programming Error 7.5
Placing an ellipsis indicating a variable-length argument list in the middle of a parameter
list is a syntax error. An ellipsis may be placed only at the end of the parameter list.
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// Fig. 7.20: VarargsTest.java
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// Using variable-length argument lists.
3
4
public class
VarargsTest
5
{
6
// calculate average
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public static double
average(
double
... numbers
)
8
{
9
double
total =
0.0
;
10
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// calculate total using the enhanced for statement
12
for
(
double
d : numbers)
total += d;
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14
15
numbers.length
return
total /
;
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}
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public static void
main(String[] args)
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{
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double
d1 =
10.0
;
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double
d2 =
20.0
;
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double
d3 =
30.0
;
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double
d4 =
40.0
;
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System.out.printf(
"d1 = %.1f%nd2 = %.1f%nd3 = %.1f%nd4 = %.1f%n%n"
,
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d1, d2, d3, d4);
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System.out.printf(
"Average of d1 and d2 is %.1f%n"
,
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average(d1, d2)
);
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System.out.printf(
"Average of d1, d2 and d3 is %.1f%n"
,
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average(d1, d2, d3)
);
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System.out.printf(
"Average of d1, d2, d3 and d4 is %.1f%n"
,
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average(d1, d2, d3, d4)
);
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}
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}
// end class VarargsTest
d1 = 10.0
d2 = 20.0
d3 = 30.0
d4 = 40.0
Average of d1 and d2 is 15.0
Average of d1, d2 and d3 is 20.0
Average of d1, d2, d3 and d4 is 25.0
Fig. 7.20
|
Using variable-length argument lists.
