1 |
jsr166 |
1.1 |
/* |
2 |
|
|
* Written by Doug Lea and Martin Buchholz with assistance from |
3 |
|
|
* members of JCP JSR-166 Expert Group and released to the public |
4 |
|
|
* domain, as explained at |
5 |
|
|
* http://creativecommons.org/publicdomain/zero/1.0/ |
6 |
|
|
*/ |
7 |
|
|
|
8 |
|
|
import static java.util.concurrent.TimeUnit.MILLISECONDS; |
9 |
|
|
|
10 |
|
|
import java.util.ArrayList; |
11 |
|
|
import java.util.Collection; |
12 |
|
|
import java.util.List; |
13 |
|
|
import java.util.Set; |
14 |
|
|
import java.util.HashSet; |
15 |
|
|
import java.util.concurrent.Callable; |
16 |
|
|
import java.util.concurrent.CompletionService; |
17 |
|
|
import java.util.concurrent.ExecutionException; |
18 |
|
|
import java.util.concurrent.ExecutorCompletionService; |
19 |
|
|
import java.util.concurrent.Executor; |
20 |
|
|
import java.util.concurrent.ExecutorService; |
21 |
|
|
import java.util.concurrent.ForkJoinPool; |
22 |
|
|
import java.util.concurrent.Future; |
23 |
|
|
|
24 |
|
|
import junit.framework.Test; |
25 |
|
|
import junit.framework.TestSuite; |
26 |
|
|
|
27 |
|
|
public class ExecutorCompletionService9Test extends JSR166TestCase { |
28 |
|
|
public static void main(String[] args) { |
29 |
|
|
main(suite(), args); |
30 |
|
|
} |
31 |
|
|
public static Test suite() { |
32 |
|
|
return new TestSuite(ExecutorCompletionService9Test.class); |
33 |
|
|
} |
34 |
|
|
|
35 |
|
|
void solveAll(Executor e, |
36 |
|
|
Collection<Callable<Integer>> solvers) |
37 |
|
|
throws InterruptedException, ExecutionException { |
38 |
|
|
CompletionService<Integer> cs |
39 |
|
|
= new ExecutorCompletionService<>(e); |
40 |
|
|
solvers.forEach((solver) -> cs.submit(solver)); |
41 |
|
|
for (int i = solvers.size(); i > 0; i--) { |
42 |
|
|
Integer r = cs.take().get(); |
43 |
|
|
if (r != null) |
44 |
|
|
use(r); |
45 |
|
|
} |
46 |
|
|
} |
47 |
|
|
|
48 |
|
|
void solveAny(Executor e, |
49 |
|
|
Collection<Callable<Integer>> solvers) |
50 |
|
|
throws InterruptedException { |
51 |
|
|
CompletionService<Integer> cs |
52 |
|
|
= new ExecutorCompletionService<>(e); |
53 |
|
|
int n = solvers.size(); |
54 |
|
|
List<Future<Integer>> futures = new ArrayList<>(n); |
55 |
|
|
Integer result = null; |
56 |
|
|
try { |
57 |
|
|
solvers.forEach((solver) -> futures.add(cs.submit(solver))); |
58 |
|
|
for (int i = n; i > 0; i--) { |
59 |
|
|
try { |
60 |
|
|
Integer r = cs.take().get(); |
61 |
|
|
if (r != null) { |
62 |
|
|
result = r; |
63 |
|
|
break; |
64 |
|
|
} |
65 |
|
|
} catch (ExecutionException ignore) {} |
66 |
|
|
} |
67 |
|
|
} finally { |
68 |
|
|
futures.forEach((future) -> future.cancel(true)); |
69 |
|
|
} |
70 |
|
|
|
71 |
|
|
if (result != null) |
72 |
|
|
use(result); |
73 |
|
|
} |
74 |
|
|
|
75 |
|
|
HashSet<Integer> results; |
76 |
|
|
|
77 |
|
|
void use(Integer x) { |
78 |
|
|
if (results == null) results = new HashSet<Integer>(); |
79 |
|
|
results.add(x); |
80 |
|
|
} |
81 |
|
|
|
82 |
|
|
/** |
83 |
|
|
* The first "solvers" sample code in the class javadoc works. |
84 |
|
|
*/ |
85 |
|
|
public void testSolveAll() |
86 |
|
|
throws InterruptedException, ExecutionException { |
87 |
|
|
Set<Callable<Integer>> solvers = Set.of( |
88 |
|
|
() -> null, |
89 |
|
|
() -> 1, |
90 |
|
|
() -> 2, |
91 |
|
|
() -> 3, |
92 |
|
|
() -> null); |
93 |
|
|
solveAll(ForkJoinPool.commonPool(), solvers); |
94 |
|
|
assertEquals(Set.of(1, 2, 3), results); |
95 |
|
|
} |
96 |
|
|
|
97 |
|
|
/** |
98 |
|
|
* The second "solvers" sample code in the class javadoc works. |
99 |
|
|
*/ |
100 |
|
|
public void testSolveAny() |
101 |
|
|
throws InterruptedException { |
102 |
|
|
Set<Callable<Integer>> solvers = Set.of( |
103 |
|
|
() -> { throw new ArithmeticException(); }, |
104 |
|
|
() -> null, |
105 |
|
|
() -> 1, |
106 |
|
|
() -> 2); |
107 |
|
|
solveAny(ForkJoinPool.commonPool(), solvers); |
108 |
|
|
assertEquals(1, results.size()); |
109 |
|
|
Integer elt = results.iterator().next(); |
110 |
|
|
assertTrue(elt.equals(1) || elt.equals(2)); |
111 |
|
|
} |
112 |
|
|
|
113 |
|
|
} |