FazBrowse GitHub Viewer
|
Trending
|
URL:
|
Home
Tools:
[Download Repo ZIP]
[View Raw Code]
[Original HTTPS Page]
OnJava8-Examples/concurrent/Summing2.java at master · CSapprenticeWT/OnJava8-Examples · GitHub
CSapprenticeWT
OnJava8-Examples
Repository navigation
Code
Pull requests
Actions
Projects
Security and quality
Insights
Expand file tree
Breadcrumbs
OnJava8-Examples
/
concurrent
/
Summing2.java
Copy path
More file actions
More file actions
Latest commit
History
History
History
44 lines (43 loc) · 1.25 KB
Breadcrumbs
OnJava8-Examples
/
concurrent
/
Summing2.java
Copy path
File metadata and controls
44 lines (43 loc) · 1.25 KB
Raw
Copy raw file
Download raw file
Open symbols panel
Edit and raw actions
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
// concurrent/Summing2.java
// (c)2021 MindView LLC: see Copyright.txt
// We make no guarantees that this code is fit for any purpose.
// Visit http://OnJava8.com for more book information.
// {ExcludeFromTravisCI}
import
java
.
util
.*;
public
class
Summing2
{
static
long
basicSum
(
long
[]
ia
) {
long
sum
=
0
;
int
size
=
ia
.
length
;
for
(
int
i
=
0
;
i
<
size
;
i
++)
sum
+=
ia
[
i
];
return
sum
;
}
// Approximate largest value of SZ before
// running out of memory on my machine:
public
static
final
int
SZ
=
20_000_000
;
public
static
final
long
CHECK
=
(
long
)
SZ
* ((
long
)
SZ
+
1
)/
2
;
public
static
void
main
(
String
[]
args
) {
System
.
out
.
println
(
CHECK
);
long
[]
la
=
new
long
[
SZ
+
1
];
Arrays
.
parallelSetAll
(
la
,
i
->
i
);
Summing
.
timeTest
(
"Array Stream Sum"
,
CHECK
, () ->
Arrays
.
stream
(
la
).
sum
());
Summing
.
timeTest
(
"Parallel"
,
CHECK
, () ->
Arrays
.
stream
(
la
).
parallel
().
sum
());
Summing
.
timeTest
(
"Basic Sum"
,
CHECK
, () ->
basicSum
(
la
));
// Destructive summation:
Summing
.
timeTest
(
"parallelPrefix"
,
CHECK
, () -> {
Arrays
.
parallelPrefix
(
la
,
Long
::
sum
);
return
la
[
la
.
length
-
1
];
});
}
}
/* Output:
200000010000000
Array Stream Sum: 166ms
Parallel: 30ms
Basic Sum: 45ms
parallelPrefix: 53ms
*/
Back
|
FazBrowse Home
|
New Git URL