2019-03-25 11:57:27 +01:00
|
|
|
/**
|
|
|
|
*
|
|
|
|
* Copyright 2019 Florian Schmaus
|
|
|
|
*
|
|
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
|
|
* you may not use this file except in compliance with the License.
|
|
|
|
* You may obtain a copy of the License at
|
|
|
|
*
|
|
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
|
|
*
|
|
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
|
|
* See the License for the specific language governing permissions and
|
|
|
|
* limitations under the License.
|
|
|
|
*/
|
|
|
|
package org.jivesoftware.smack.util;
|
|
|
|
|
|
|
|
import static org.junit.Assert.assertNull;
|
2019-05-09 12:09:06 +02:00
|
|
|
import static org.junit.jupiter.api.Assertions.fail;
|
2019-03-25 11:57:27 +01:00
|
|
|
|
|
|
|
import java.lang.ref.PhantomReference;
|
|
|
|
import java.lang.ref.Reference;
|
|
|
|
import java.lang.ref.ReferenceQueue;
|
|
|
|
import java.lang.ref.WeakReference;
|
|
|
|
import java.util.ArrayList;
|
|
|
|
import java.util.HashSet;
|
|
|
|
import java.util.List;
|
|
|
|
import java.util.Set;
|
|
|
|
import java.util.function.Function;
|
|
|
|
import java.util.logging.Logger;
|
|
|
|
|
|
|
|
import org.jivesoftware.smack.DummyConnection;
|
|
|
|
import org.jivesoftware.smack.Manager;
|
|
|
|
|
|
|
|
import org.jxmpp.stringprep.XmppStringprepException;
|
|
|
|
|
|
|
|
/**
|
|
|
|
* Utility class to test for memory leaks caused by Smack.
|
|
|
|
* <p>
|
|
|
|
* Note that this test is based on the assumption that it is possible to trigger a full garbage collection run, which is
|
|
|
|
* not the case. See also this
|
|
|
|
* <a href="https://stackoverflow.com/questions/1481178/how-to-force-garbage-collection-in-java">stackoverflow
|
|
|
|
* question</a>. Hence the {@link #triggerGarbageCollection()} method defined in this class is not portable and depends
|
|
|
|
* on implementation depended Java Virtual Machine behavior.
|
|
|
|
* </p>
|
|
|
|
*
|
|
|
|
* @see <a href="https://issues.igniterealtime.org/browse/SMACK-383">SMACK-383 Jira Issue</a>
|
|
|
|
*/
|
|
|
|
public class MemoryLeakTestUtil {
|
|
|
|
|
|
|
|
private static final Logger LOGGER = Logger.getLogger(MemoryLeakTestUtil.class.getName());
|
|
|
|
|
2019-05-07 22:58:02 +02:00
|
|
|
@SuppressWarnings("UnusedVariable")
|
2019-03-25 11:57:27 +01:00
|
|
|
public static <M extends Manager> void noResourceLeakTest(Function<DummyConnection, M> managerSupplier)
|
|
|
|
throws XmppStringprepException, IllegalArgumentException, InterruptedException {
|
|
|
|
final int numConnections = 10;
|
|
|
|
|
|
|
|
ReferenceQueue<DummyConnection> connectionsReferenceQueue = new ReferenceQueue<>();
|
|
|
|
ReferenceQueue<Manager> managerReferenceQueue = new ReferenceQueue<>();
|
|
|
|
|
|
|
|
// Those two sets ensure that we hold a strong reference to the created PhantomReferences until the end of the
|
|
|
|
// test.
|
|
|
|
@SuppressWarnings("ModifiedButNotUsed")
|
|
|
|
Set<PhantomReference<DummyConnection>> connectionsPhantomReferences = new HashSet<>();
|
|
|
|
@SuppressWarnings("ModifiedButNotUsed")
|
|
|
|
Set<PhantomReference<Manager>> managersPhantomReferences = new HashSet<>();
|
|
|
|
|
|
|
|
List<DummyConnection> connections = new ArrayList<>(numConnections);
|
|
|
|
for (int i = 0; i < numConnections; i++) {
|
|
|
|
DummyConnection connection = new DummyConnection("foo" + i, "bar", "baz");
|
|
|
|
|
|
|
|
PhantomReference<DummyConnection> connectionPhantomReference = new PhantomReference<>(connection, connectionsReferenceQueue);
|
|
|
|
connectionsPhantomReferences.add(connectionPhantomReference);
|
|
|
|
|
|
|
|
Manager manager = managerSupplier.apply(connection);
|
|
|
|
PhantomReference<Manager> managerPhantomReference = new PhantomReference<Manager>(manager, managerReferenceQueue);
|
|
|
|
managersPhantomReferences.add(managerPhantomReference);
|
|
|
|
|
|
|
|
connections.add(connection);
|
|
|
|
}
|
|
|
|
|
|
|
|
// Clear the only references to the created connections.
|
|
|
|
connections = null;
|
|
|
|
|
|
|
|
triggerGarbageCollection();
|
|
|
|
|
|
|
|
// Now the connections should have been gc'ed, but not managers not yet.
|
|
|
|
assertReferencesQueueSize(connectionsReferenceQueue, numConnections);
|
|
|
|
assertReferencesQueueIsEmpty(managerReferenceQueue);
|
|
|
|
|
|
|
|
// We new create another connection and explicitly a new Manager. This will trigger the cleanup mechanism in the
|
|
|
|
// WeakHashMaps used by the Manager's iNSTANCE field. This should clean up all references to the Managers.
|
|
|
|
DummyConnection connection = new DummyConnection("last", "bar", "baz");
|
|
|
|
@SuppressWarnings("unused")
|
|
|
|
Manager manager = managerSupplier.apply(connection);
|
|
|
|
|
|
|
|
// The previous Managers should now be reclaimable by the garbage collector. First trigger a GC run.
|
|
|
|
triggerGarbageCollection();
|
|
|
|
|
|
|
|
// Now the Managers should have been freed and this means we should see their phantom references in the
|
|
|
|
// reference queue.
|
|
|
|
assertReferencesQueueSize(managerReferenceQueue, numConnections);
|
|
|
|
}
|
|
|
|
|
|
|
|
private static void assertReferencesQueueSize(ReferenceQueue<?> referenceQueue, int expectedSize) throws IllegalArgumentException, InterruptedException {
|
2019-05-08 11:35:32 +02:00
|
|
|
final int timeout = 120000;
|
2019-05-09 12:09:06 +02:00
|
|
|
final int maxAttempts = 3;
|
2019-03-25 11:57:27 +01:00
|
|
|
for (int itemsRemoved = 0; itemsRemoved < expectedSize; ++itemsRemoved) {
|
2019-05-09 12:09:06 +02:00
|
|
|
int attempt = 0;
|
|
|
|
Reference<?> reference = null;
|
|
|
|
do {
|
|
|
|
reference = referenceQueue.remove(timeout);
|
|
|
|
if (reference != null) {
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
|
|
|
|
attempt++;
|
|
|
|
String message = "No reference to a gc'ed object found after " + timeout + "ms in the " + attempt
|
|
|
|
+ ". attempt.";
|
|
|
|
if (attempt >= maxAttempts) {
|
|
|
|
fail(message);
|
|
|
|
}
|
|
|
|
|
|
|
|
LOGGER.warning(message);
|
|
|
|
triggerGarbageCollection();
|
|
|
|
} while (true);
|
2019-03-25 11:57:27 +01:00
|
|
|
reference.clear();
|
|
|
|
}
|
|
|
|
|
|
|
|
Reference<?> reference = referenceQueue.poll();
|
|
|
|
assertNull("Reference queue is not empty when it should be", reference);
|
|
|
|
}
|
|
|
|
|
|
|
|
private static void assertReferencesQueueIsEmpty(ReferenceQueue<?> referenceQueue) {
|
|
|
|
Reference<?> reference = referenceQueue.poll();
|
|
|
|
assertNull(reference);
|
|
|
|
}
|
|
|
|
|
2019-05-07 22:58:02 +02:00
|
|
|
@SuppressWarnings("UnusedVariable")
|
2019-03-25 11:57:27 +01:00
|
|
|
private static void triggerGarbageCollection() {
|
|
|
|
Object object = new Object();
|
|
|
|
WeakReference<Object> weakReference = new WeakReference<>(object);
|
|
|
|
object = null;
|
|
|
|
|
|
|
|
int gcCalls = 0;
|
|
|
|
do {
|
|
|
|
if (gcCalls > 1000) {
|
|
|
|
throw new AssertionError("No observed gargabe collection after " + gcCalls + " calls of System.gc()");
|
|
|
|
}
|
|
|
|
System.gc();
|
2019-05-09 12:06:01 +02:00
|
|
|
// TODO: Would a Thread.yield() here improve the chances of a full GC? It appears that on some systems we
|
|
|
|
// observe a partial GC here.
|
2019-03-25 11:57:27 +01:00
|
|
|
gcCalls++;
|
|
|
|
} while (weakReference.get() != null);
|
|
|
|
|
|
|
|
// Note that this is no guarantee that a *full* garbage collection run has been made, which is what we actually
|
|
|
|
// need here in order to prevent false negatives.
|
|
|
|
LOGGER.finer("Observed garbage collection after " + gcCalls + " calls of System.gc()");
|
|
|
|
}
|
|
|
|
}
|