| 16 |
|
import java.util.NoSuchElementException; |
| 17 |
|
import java.util.Set; |
| 18 |
|
import java.util.Spliterator; |
| 19 |
+ |
import java.util.concurrent.ExecutorService; |
| 20 |
+ |
import java.util.concurrent.Executors; |
| 21 |
|
import java.util.concurrent.ConcurrentHashMap; |
| 22 |
|
import java.util.concurrent.atomic.LongAdder; |
| 23 |
|
import java.util.function.BiFunction; |
| 1089 |
|
assertNull(r); |
| 1090 |
|
} |
| 1091 |
|
|
| 1092 |
+ |
/** |
| 1093 |
+ |
* Tests performance of computeIfAbsent when the element is present. |
| 1094 |
+ |
* See JDK-8161372 |
| 1095 |
+ |
* ant -Djsr166.tckTestClass=ConcurrentHashMapTest -Djsr166.methodFilter=testcomputeIfAbsent_performance -Djsr166.expensiveTests=true tck |
| 1096 |
+ |
*/ |
| 1097 |
+ |
public void testcomputeIfAbsent_performance() { |
| 1098 |
+ |
final int mapSize = 20; |
| 1099 |
+ |
final int iterations = expensiveTests ? (1 << 23) : mapSize * 2; |
| 1100 |
+ |
final int threads = expensiveTests ? 10 : 2; |
| 1101 |
+ |
final ConcurrentHashMap<Integer, Integer> map = new ConcurrentHashMap<>(); |
| 1102 |
+ |
for (int i = 0; i < mapSize; i++) |
| 1103 |
+ |
map.put(i, i); |
| 1104 |
+ |
final ExecutorService pool = Executors.newFixedThreadPool(2); |
| 1105 |
+ |
try (PoolCleaner cleaner = cleaner(pool)) { |
| 1106 |
+ |
Runnable r = new CheckedRunnable() { |
| 1107 |
+ |
public void realRun() { |
| 1108 |
+ |
int result = 0; |
| 1109 |
+ |
for (int i = 0; i < iterations; i++) |
| 1110 |
+ |
result += map.computeIfAbsent(i % mapSize, (k) -> k + k); |
| 1111 |
+ |
if (result == -42) throw new Error(); |
| 1112 |
+ |
}}; |
| 1113 |
+ |
for (int i = 0; i < threads; i++) |
| 1114 |
+ |
pool.execute(r); |
| 1115 |
+ |
} |
| 1116 |
+ |
} |
| 1117 |
+ |
|
| 1118 |
|
} |
