/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.apache.commons.pool2.impl;
import java.io.BufferedOutputStream;
import java.io.ByteArrayOutputStream;
import java.io.PrintWriter;
import java.lang.management.ManagementFactory;
import java.util.ArrayList;
import java.util.Objects;
import java.util.Set;
import java.util.concurrent.atomic.AtomicInteger;
import javax.management.MBeanServer;
import javax.management.ObjectName;
import org.apache.commons.pool2.PooledObject;
import org.apache.commons.pool2.PooledObjectFactory;
import org.apache.commons.pool2.TrackedUse;
import org.junit.After;
import org.junit.Assert;
import org.junit.Before;
import org.junit.Test;
/**
* TestCase for AbandonedObjectPool
*/
public class TestAbandonedObjectPool {
private GenericObjectPool<PooledTestObject> pool = null;
private AbandonedConfig abandonedConfig = null;
@Before
public void setUp() throws Exception {
abandonedConfig = new AbandonedConfig();
// -- Uncomment the following line to enable logging --
// abandonedConfig.setLogAbandoned(true);
abandonedConfig.setRemoveAbandonedOnBorrow(true);
abandonedConfig.setRemoveAbandonedTimeout(1);
pool = new GenericObjectPool<>(
new SimpleFactory(),
new GenericObjectPoolConfig<PooledTestObject>(),
abandonedConfig);
}
@After
public void tearDown() throws Exception {
final String poolName = pool.getJmxName().toString();
pool.clear();
pool.close();
pool = null;
final MBeanServer mbs = ManagementFactory.getPlatformMBeanServer();
final Set<ObjectName> result = mbs.queryNames(new ObjectName(
"org.apache.commoms.pool2:type=GenericObjectPool,*"), null);
// There should be no registered pools at this point
final int registeredPoolCount = result.size();
final StringBuilder msg = new StringBuilder("Current pool is: ");
msg.append(poolName);
msg.append(" Still open pools are: ");
for (final ObjectName name : result) {
// Clean these up ready for the next test
msg.append(name.toString());
msg.append(" created via\n");
msg.append(mbs.getAttribute(name, "CreationStackTrace"));
msg.append('\n');
mbs.unregisterMBean(name);
}
Assert.assertEquals(msg.toString(), 0, registeredPoolCount);
}
/**
* Tests fix for Bug 28579, a bug in AbandonedObjectPool that causes numActive to go negative
* in GenericObjectPool
*
* @throws Exception May occur in some failure modes
*/
@Test
public void testConcurrentInvalidation() throws Exception {
final int POOL_SIZE = 30;
pool.setMaxTotal(POOL_SIZE);
pool.setMaxIdle(POOL_SIZE);
pool.setBlockWhenExhausted(false);
// Exhaust the connection pool
final ArrayList<PooledTestObject> vec = new ArrayList<>();
for (int i = 0; i < POOL_SIZE; i++) {
vec.add(pool.borrowObject());
}
// Abandon all borrowed objects
for (final PooledTestObject element : vec) {
element.setAbandoned(true);
}
// Try launching a bunch of borrows concurrently. Abandoned sweep will be triggered for each.
final int CONCURRENT_BORROWS = 5;
final Thread[] threads = new Thread[CONCURRENT_BORROWS];
for (int i = 0; i < CONCURRENT_BORROWS; i++) {
threads[i] = new ConcurrentBorrower(vec);
threads[i].start();
}
// Wait for all the threads to finish
for (int i = 0; i < CONCURRENT_BORROWS; i++) {
threads[i].join();
}
// Return all objects that have not been destroyed
for (final PooledTestObject pto : vec) {
if (pto.isActive()) {
pool.returnObject(pto);
}
}
// Now, the number of active instances should be 0
Assert.assertTrue("numActive should have been 0, was " + pool.getNumActive(), pool.getNumActive() == 0);
}
/**
* Verify that an object that gets flagged as abandoned and is subsequently returned
* is destroyed instead of being returned to the pool (and possibly later destroyed
* inappropriately).
*
* @throws Exception May occur in some failure modes
*/
@Test
public void testAbandonedReturn() throws Exception {
abandonedConfig = new AbandonedConfig();
abandonedConfig.setRemoveAbandonedOnBorrow(true);
abandonedConfig.setRemoveAbandonedTimeout(1);
pool.close(); // Unregister pool created by setup
pool = new GenericObjectPool<>(
new SimpleFactory(200, 0),
new GenericObjectPoolConfig<PooledTestObject>(), abandonedConfig);
final int n = 10;
pool.setMaxTotal(n);
pool.setBlockWhenExhausted(false);
PooledTestObject obj = null;
for (int i = 0; i < n - 2; i++) {
obj = pool.borrowObject();
}
Objects.requireNonNull(obj, "Unable to borrow object from pool");
final int deadMansHash = obj.hashCode();
final ConcurrentReturner returner = new ConcurrentReturner(obj);
Thread.sleep(2000); // abandon checked out instances
// Now start a race - returner waits until borrowObject has kicked
// off removeAbandoned and then returns an instance that borrowObject
// will deem abandoned. Make sure it is not returned to the borrower.
returner.start(); // short delay, then return instance
Assert.assertTrue(pool.borrowObject().hashCode() != deadMansHash);
Assert.assertEquals(0, pool.getNumIdle());
Assert.assertEquals(1, pool.getNumActive());
}
/**
* Verify that an object that gets flagged as abandoned and is subsequently
* invalidated is only destroyed (and pool counter decremented) once.
*
* @throws Exception May occur in some failure modes
*/
@Test
public void testAbandonedInvalidate() throws Exception {
abandonedConfig = new AbandonedConfig();
abandonedConfig.setRemoveAbandonedOnMaintenance(true);
abandonedConfig.setRemoveAbandonedTimeout(1);
pool.close(); // Unregister pool created by setup
pool = new GenericObjectPool<>(
// destroys take 200 ms
new SimpleFactory(200, 0),
new GenericObjectPoolConfig<PooledTestObject>(), abandonedConfig);
final int n = 10;
pool.setMaxTotal(n);
pool.setBlockWhenExhausted(false);
pool.setTimeBetweenEvictionRunsMillis(500);
PooledTestObject obj = null;
for (int i = 0; i < 5; i++) {
obj = pool.borrowObject();
}
Thread.sleep(1000); // abandon checked out instances and let evictor start
pool.invalidateObject(obj); // Should not trigger another destroy / decrement
Thread.sleep(2000); // give evictor time to finish destroys
Assert.assertEquals(0, pool.getNumActive());
Assert.assertEquals(5, pool.getDestroyedCount());
}
/**
* Verify that an object that the evictor identifies as abandoned while it
* is in process of being returned to the pool is not destroyed.
*
* @throws Exception May occur in some failure modes
*/
@Test
public void testRemoveAbandonedWhileReturning() throws Exception {
abandonedConfig = new AbandonedConfig();
abandonedConfig.setRemoveAbandonedOnMaintenance(true);
abandonedConfig.setRemoveAbandonedTimeout(1);
pool.close(); // Unregister pool created by setup
pool = new GenericObjectPool<>(
// validate takes 1 second
new SimpleFactory(0, 1000),
new GenericObjectPoolConfig<PooledTestObject>(), abandonedConfig);
final int n = 10;
pool.setMaxTotal(n);
pool.setBlockWhenExhausted(false);
pool.setTimeBetweenEvictionRunsMillis(500);
pool.setTestOnReturn(true);
// Borrow an object, wait long enough for it to be abandoned
// then arrange for evictor to run while it is being returned
// validation takes a second, evictor runs every 500 ms
final PooledTestObject obj = pool.borrowObject();
Thread.sleep(50); // abandon obj
pool.returnObject(obj); // evictor will run during validation
final PooledTestObject obj2 = pool.borrowObject();
Assert.assertEquals(obj, obj2); // should get original back
Assert.assertTrue(!obj2.isDestroyed()); // and not destroyed
}
/**
* Test case for https://issues.apache.org/jira/browse/DBCP-260.
* Borrow and abandon all the available objects then attempt to borrow one
* further object which should block until the abandoned objects are
* removed. We don't want the test to block indefinitely when it fails so
* use maxWait be check we don't actually have to wait that long.
*
* @throws Exception May occur in some failure modes
*/
@Test
public void testWhenExhaustedBlock() throws Exception {
abandonedConfig.setRemoveAbandonedOnMaintenance(true);
pool.setAbandonedConfig(abandonedConfig);
pool.setTimeBetweenEvictionRunsMillis(500);
pool.setMaxTotal(1);
@SuppressWarnings("unused") // This is going to be abandoned
final
PooledTestObject o1 = pool.borrowObject();
final long start = System.currentTimeMillis();
final PooledTestObject o2 = pool.borrowObject(5000);
final long end = System.currentTimeMillis();
pool.returnObject(o2);
Assert.assertTrue (end - start < 5000);
}
/**
* JIRA: POOL-300
*/
@Test
public void testStackTrace() throws Exception {
abandonedConfig.setRemoveAbandonedOnMaintenance(true);
abandonedConfig.setLogAbandoned(true);
abandonedConfig.setRemoveAbandonedTimeout(1);
final ByteArrayOutputStream baos = new ByteArrayOutputStream();
final BufferedOutputStream bos = new BufferedOutputStream(baos);
final PrintWriter pw = new PrintWriter(bos);
abandonedConfig.setLogWriter(pw);
pool.setAbandonedConfig(abandonedConfig);
pool.setTimeBetweenEvictionRunsMillis(100);
final PooledTestObject o1 = pool.borrowObject();
Thread.sleep(2000);
Assert.assertTrue(o1.isDestroyed());
bos.flush();
Assert.assertTrue(baos.toString().indexOf("Pooled object") >= 0);
}
class ConcurrentBorrower extends Thread {
private final ArrayList<PooledTestObject> _borrowed;
public ConcurrentBorrower(final ArrayList<PooledTestObject> borrowed) {
_borrowed = borrowed;
}
@Override
public void run() {
try {
_borrowed.add(pool.borrowObject());
} catch (final Exception e) {
// expected in most cases
}
}
}
class ConcurrentReturner extends Thread {
private final PooledTestObject returned;
public ConcurrentReturner(final PooledTestObject obj) {
returned = obj;
}
@Override
public void run() {
try {
sleep(20);
pool.returnObject(returned);
} catch (final Exception e) {
// ignore
}
}
}
private static class SimpleFactory implements PooledObjectFactory<PooledTestObject> {
private final long destroyLatency;
private final long validateLatency;
public SimpleFactory() {
destroyLatency = 0;
validateLatency = 0;
}
public SimpleFactory(final long destroyLatency, final long validateLatency) {
this.destroyLatency = destroyLatency;
this.validateLatency = validateLatency;
}
@Override
public PooledObject<PooledTestObject> makeObject() {
return new DefaultPooledObject<>(new PooledTestObject());
}
@Override
public boolean validateObject(final PooledObject<PooledTestObject> obj) {
try {
Thread.sleep(validateLatency);
} catch (final Exception ex) {
// ignore
}
return true;
}
@Override
public void activateObject(final PooledObject<PooledTestObject> obj) {
obj.getObject().setActive(true);
}
@Override
public void passivateObject(final PooledObject<PooledTestObject> obj) {
obj.getObject().setActive(false);
}
@Override
public void destroyObject(final PooledObject<PooledTestObject> obj) throws Exception {
obj.getObject().setActive(false);
// while destroying instances, yield control to other threads
// helps simulate threading errors
Thread.yield();
if (destroyLatency != 0) {
Thread.sleep(destroyLatency);
}
obj.getObject().destroy();
}
}
}
class PooledTestObject implements TrackedUse {
private boolean active = false;
private boolean destroyed = false;
private int _hash = 0;
private boolean _abandoned = false;
private static final AtomicInteger hash = new AtomicInteger();
public PooledTestObject() {
_hash = hash.incrementAndGet();
}
public synchronized void setActive(final boolean b) {
active = b;
}
public synchronized boolean isActive() {
return active;
}
public void destroy() {
destroyed = true;
}
public boolean isDestroyed() {
return destroyed;
}
@Override
public int hashCode() {
return _hash;
}
public void setAbandoned(final boolean b) {
_abandoned = b;
}
@Override
public long getLastUsed() {
if (_abandoned) {
// Abandoned object sweep will occur no matter what the value of removeAbandonedTimeout,
// because this indicates that this object was last used decades ago
return 1;
}
// Abandoned object sweep won't clean up this object
return 0;
}
@Override
public boolean equals(final Object obj) {
if (!(obj instanceof PooledTestObject)) {
return false;
}
return obj.hashCode() == hashCode();
}
}
