48 lines
1.2 KiB
Java
48 lines
1.2 KiB
Java
// concurrent/CachedThreadPool3.java
|
|
// (c)2017 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.
|
|
import java.util.*;
|
|
import java.util.concurrent.*;
|
|
import java.util.stream.*;
|
|
|
|
public class CachedThreadPool3 {
|
|
public static Integer
|
|
extractResult(Future<Integer> f) {
|
|
try {
|
|
return f.get();
|
|
} catch(Exception e) {
|
|
throw new RuntimeException(e);
|
|
}
|
|
}
|
|
public static void main(String[] args)
|
|
throws InterruptedException {
|
|
ExecutorService exec =
|
|
Executors.newCachedThreadPool();
|
|
List<CountingTask> tasks =
|
|
IntStream.range(0, 10)
|
|
.mapToObj(CountingTask::new)
|
|
.collect(Collectors.toList());
|
|
List<Future<Integer>> futures =
|
|
exec.invokeAll(tasks);
|
|
Integer sum = futures.stream()
|
|
.map(CachedThreadPool3::extractResult)
|
|
.reduce(0, Integer::sum);
|
|
System.out.println("sum = " + sum);
|
|
exec.shutdown();
|
|
}
|
|
}
|
|
/* Output:
|
|
2 pool-1-thread-3 100
|
|
6 pool-1-thread-7 100
|
|
5 pool-1-thread-6 100
|
|
7 pool-1-thread-8 100
|
|
4 pool-1-thread-5 100
|
|
9 pool-1-thread-10 100
|
|
3 pool-1-thread-4 100
|
|
0 pool-1-thread-1 100
|
|
1 pool-1-thread-2 100
|
|
8 pool-1-thread-9 100
|
|
sum = 1000
|
|
*/
|