public static ByteBufferIndexInput newInstance(
String resourceDescription,
ByteBuffer[] buffers,
long length,
int chunkSizePower,
BufferCleaner cleaner,
boolean trackClones) {
final WeakIdentityMap<ByteBufferIndexInput, Boolean> clones =
trackClones ? WeakIdentityMap.<ByteBufferIndexInput, Boolean>newConcurrentHashMap() : null;
if (buffers.length == 1) {
return new SingleBufferImpl(
resourceDescription, buffers[0], length, chunkSizePower, cleaner, clones);
} else {
return new DefaultImpl(resourceDescription, buffers, length, chunkSizePower, cleaner, clones);
}
}
public void testConcurrentHashMap() throws Exception {
// don't make threadCount and keyCount random, otherwise easily OOMs or fails otherwise:
final int threadCount = 8, keyCount = 1024;
final ExecutorService exec =
Executors.newFixedThreadPool(threadCount, new NamedThreadFactory("testConcurrentHashMap"));
final WeakIdentityMap<Object, Integer> map =
WeakIdentityMap.newConcurrentHashMap(random().nextBoolean());
// we keep strong references to the keys,
// so WeakIdentityMap will not forget about them:
final AtomicReferenceArray<Object> keys = new AtomicReferenceArray<Object>(keyCount);
for (int j = 0; j < keyCount; j++) {
keys.set(j, new Object());
}
try {
for (int t = 0; t < threadCount; t++) {
final Random rnd = new Random(random().nextLong());
exec.execute(
new Runnable() {
@Override
public void run() {
final int count = atLeast(rnd, 10000);
for (int i = 0; i < count; i++) {
final int j = rnd.nextInt(keyCount);
switch (rnd.nextInt(5)) {
case 0:
map.put(keys.get(j), Integer.valueOf(j));
break;
case 1:
final Integer v = map.get(keys.get(j));
if (v != null) {
assertEquals(j, v.intValue());
}
break;
case 2:
map.remove(keys.get(j));
break;
case 3:
// renew key, the old one will be GCed at some time:
keys.set(j, new Object());
break;
case 4:
// check iterator still working
for (Iterator<Object> it = map.keyIterator(); it.hasNext(); ) {
assertNotNull(it.next());
}
break;
default:
fail("Should not get here.");
}
}
}
});
}
} finally {
exec.shutdown();
while (!exec.awaitTermination(1000L, TimeUnit.MILLISECONDS)) ;
}
// clear strong refs
for (int j = 0; j < keyCount; j++) {
keys.set(j, null);
}
// check that GC does not cause problems in reap() method:
int size = map.size();
for (int i = 0; size > 0 && i < 10; i++)
try {
System.runFinalization();
System.gc();
int newSize = map.size();
assertTrue("previousSize(" + size + ")>=newSize(" + newSize + ")", size >= newSize);
size = newSize;
Thread.sleep(100L);
int c = 0;
for (Iterator<Object> it = map.keyIterator(); it.hasNext(); ) {
assertNotNull(it.next());
c++;
}
newSize = map.size();
assertTrue("previousSize(" + size + ")>=iteratorSize(" + c + ")", size >= c);
assertTrue("iteratorSize(" + c + ")>=newSize(" + newSize + ")", c >= newSize);
size = newSize;
} catch (InterruptedException ie) {
}
}