org.htmlunit.javascript.background.JavaScriptJobManagerImpl Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of xlt Show documentation
Show all versions of xlt Show documentation
XLT (Xceptance LoadTest) is an extensive load and performance test tool developed and maintained by Xceptance.
The newest version!
/*
* Copyright (c) 2002-2024 Gargoyle Software Inc.
*
* 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
* https://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.htmlunit.javascript.background;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.lang.ref.WeakReference;
import java.util.ArrayList;
import java.util.PriorityQueue;
import java.util.concurrent.atomic.AtomicInteger;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.htmlunit.Page;
import org.htmlunit.WebWindow;
/**
* Default implementation of {@link JavaScriptJobManager}.
*
* This job manager class is guaranteed not to keep old windows in memory (no window memory leaks).
*
* This job manager is serializable, but any running jobs are transient and are not serialized.
*
* @author Daniel Gredler
* @author Katharina Probst
* @author Amit Manjhi
* @author Ronald Brill
* @author Carsten Steul
*/
class JavaScriptJobManagerImpl implements JavaScriptJobManager {
/**
* The window to which this job manager belongs (weakly referenced, so as not
* to leak memory).
*/
private final transient WeakReference window_;
/**
* Queue of jobs that are scheduled to run. This is a priority queue, sorted
* by closest target execution time.
*/
private transient PriorityQueue scheduledJobsQ_ = new PriorityQueue<>();
private transient ArrayList cancelledJobs_ = new ArrayList<>();
private transient JavaScriptJob currentlyRunningJob_;
/** A counter used to generate the IDs assigned to {@link JavaScriptJob}s. */
private static final AtomicInteger NEXT_JOB_ID_ = new AtomicInteger(1);
/** Logging support. */
private static final Log LOG = LogFactory.getLog(JavaScriptJobManagerImpl.class);
/**
* Creates a new instance.
*
* @param window the window associated with the new job manager
*/
JavaScriptJobManagerImpl(final WebWindow window) {
window_ = new WeakReference<>(window);
}
/** {@inheritDoc} */
@Override
public synchronized int getJobCount() {
return scheduledJobsQ_.size() + (currentlyRunningJob_ != null ? 1 : 0);
}
/** {@inheritDoc} */
@Override
public synchronized int getJobCount(final JavaScriptJobFilter filter) {
if (filter == null) {
return scheduledJobsQ_.size() + (currentlyRunningJob_ != null ? 1 : 0);
}
int count = 0;
if (currentlyRunningJob_ != null && filter.passes(currentlyRunningJob_)) {
count++;
}
for (final JavaScriptJob job : scheduledJobsQ_) {
if (filter.passes(job)) {
count++;
}
}
return count;
}
/** {@inheritDoc} */
@Override
public int addJob(final JavaScriptJob job, final Page page) {
final WebWindow w = getWindow();
if (w == null) {
/*
* The window to which this job manager belongs has been garbage
* collected. Don't spawn any more jobs for it.
*/
return 0;
}
if (w.getEnclosedPage() != page) {
/*
* The page requesting the addition of the job is no longer contained by
* our owner window. Don't let it spawn any more jobs.
*/
return 0;
}
final int id = NEXT_JOB_ID_.getAndIncrement();
job.setId(Integer.valueOf(id));
synchronized (this) {
scheduledJobsQ_.add(job);
if (LOG.isDebugEnabled()) {
LOG.debug("job added to queue");
LOG.debug(" window is: " + w);
LOG.debug(" added job: " + job);
LOG.debug("after adding job to the queue, the queue is: ");
printQueue();
}
notify();
}
return id;
}
/** {@inheritDoc} */
@Override
public synchronized void removeJob(final int id) {
for (final JavaScriptJob job : scheduledJobsQ_) {
final int jobId = job.getId().intValue();
if (jobId == id) {
scheduledJobsQ_.remove(job);
break;
}
}
cancelledJobs_.add(Integer.valueOf(id));
notify();
}
/** {@inheritDoc} */
@Override
public synchronized void stopJob(final int id) {
for (final JavaScriptJob job : scheduledJobsQ_) {
final int jobId = job.getId().intValue();
if (jobId == id) {
scheduledJobsQ_.remove(job);
// TODO: should we try to interrupt the job if it is running?
break;
}
}
cancelledJobs_.add(Integer.valueOf(id));
notify();
}
/** {@inheritDoc} */
@Override
public synchronized void removeAllJobs() {
if (currentlyRunningJob_ != null) {
cancelledJobs_.add(currentlyRunningJob_.getId());
}
for (final JavaScriptJob job : scheduledJobsQ_) {
cancelledJobs_.add(job.getId());
}
scheduledJobsQ_.clear();
notify();
}
/** {@inheritDoc} */
@Override
public int waitForJobs(final long timeoutMillis) {
final boolean debug = LOG.isDebugEnabled();
if (debug) {
LOG.debug("Waiting for all jobs to finish (will wait max " + timeoutMillis + " millis).");
}
if (timeoutMillis > 0) {
long now = System.currentTimeMillis();
final long end = now + timeoutMillis;
synchronized (this) {
while (getJobCount() > 0 && now < end) {
try {
wait(end - now);
}
catch (final InterruptedException e) {
LOG.error("InterruptedException while in waitForJobs", e);
// restore interrupted status
Thread.currentThread().interrupt();
}
// maybe a change triggers the wakup; we have to recalculate the
// wait time
now = System.currentTimeMillis();
}
}
}
final int jobs = getJobCount();
if (debug) {
LOG.debug("Finished waiting for all jobs to finish (final job count is " + jobs + ").");
}
return jobs;
}
/** {@inheritDoc} */
@Override
public int waitForJobsStartingBefore(final long delayMillis) {
return waitForJobsStartingBefore(delayMillis, null);
}
/** {@inheritDoc} */
@Override
public int waitForJobsStartingBefore(final long delayMillis, final JavaScriptJobFilter filter) {
final boolean debug = LOG.isDebugEnabled();
final long latestExecutionTime = System.currentTimeMillis() + delayMillis;
if (debug) {
LOG.debug("Waiting for all jobs that have execution time before "
+ delayMillis + " (" + latestExecutionTime + ") to finish");
}
final long interval = Math.max(40, delayMillis);
synchronized (this) {
JavaScriptJob earliestJob = getEarliestJob(filter);
boolean pending = earliestJob != null && earliestJob.getTargetExecutionTime() < latestExecutionTime;
pending = pending
|| (
currentlyRunningJob_ != null
&& (filter == null || filter.passes(currentlyRunningJob_))
&& currentlyRunningJob_.getTargetExecutionTime() < latestExecutionTime
);
while (pending) {
try {
wait(interval);
}
catch (final InterruptedException e) {
LOG.error("InterruptedException while in waitForJobsStartingBefore", e);
// restore interrupted status
Thread.currentThread().interrupt();
}
earliestJob = getEarliestJob(filter);
pending = earliestJob != null && earliestJob.getTargetExecutionTime() < latestExecutionTime;
pending = pending
|| (
currentlyRunningJob_ != null
&& (filter == null || filter.passes(currentlyRunningJob_))
&& currentlyRunningJob_.getTargetExecutionTime() < latestExecutionTime
);
}
}
final int jobs = getJobCount(filter);
if (debug) {
LOG.debug("Finished waiting for all jobs that have target execution time earlier than "
+ latestExecutionTime + ", final job count is " + jobs);
}
return jobs;
}
/** {@inheritDoc} */
@Override
public synchronized void shutdown() {
scheduledJobsQ_.clear();
notify();
}
/**
* Returns the window to which this job manager belongs, or {@code null} if
* it has been garbage collected.
*
* @return the window to which this job manager belongs, or {@code null} if
* it has been garbage collected
*/
private WebWindow getWindow() {
return window_.get();
}
/**
* Utility method to print current queue.
*/
private void printQueue() {
if (LOG.isDebugEnabled()) {
LOG.debug("------ printing JavaScript job queue -----");
LOG.debug(" number of jobs on the queue: " + scheduledJobsQ_.size());
int count = 1;
for (final JavaScriptJob job : scheduledJobsQ_) {
LOG.debug(" " + count + ") Job target execution time: " + job.getTargetExecutionTime());
LOG.debug(" job to string: " + job);
LOG.debug(" job id: " + job.getId());
if (job.isPeriodic()) {
LOG.debug(" period: " + job.getPeriod().intValue());
}
count++;
}
LOG.debug("------------------------------------------");
}
}
/**
* INTERNAL API - SUBJECT TO CHANGE AT ANY TIME - USE AT YOUR OWN RISK.
*/
@Override
public synchronized String jobStatusDump(final JavaScriptJobFilter filter) {
final String lineSeparator = System.lineSeparator();
final StringBuilder status = new StringBuilder(110)
.append("------ JavaScript job status -----")
.append(lineSeparator);
if (null != currentlyRunningJob_ && (filter == null || filter.passes(currentlyRunningJob_))) {
status.append(" current running job: ").append(currentlyRunningJob_.toString())
.append(" job id: ").append(currentlyRunningJob_.getId())
.append(lineSeparator)
.append(lineSeparator)
.append(lineSeparator);
}
status.append(" number of jobs on the queue: ")
.append(scheduledJobsQ_.size())
.append(lineSeparator);
int count = 1;
for (final JavaScriptJob job : scheduledJobsQ_) {
if (filter == null || filter.passes(job)) {
final long now = System.currentTimeMillis();
final long execTime = job.getTargetExecutionTime();
status.append(" ").append(count).append(") Job target execution time: ")
.append(execTime).append(" (should start in ")
.append((execTime - now) / 1000d).append("s)")
.append(lineSeparator)
.append(" job to string: ").append(job)
.append(lineSeparator).append(" job id: ").append(job.getId())
.append(lineSeparator);
if (job.isPeriodic()) {
status.append(" period: ")
.append(job.getPeriod().toString())
.append(lineSeparator);
}
count++;
}
}
status.append("------------------------------------------")
.append(lineSeparator);
return status.toString();
}
/**
* {@inheritDoc}
*/
@Override
public JavaScriptJob getEarliestJob() {
return scheduledJobsQ_.peek();
}
/**
* {@inheritDoc}
*/
@Override
public synchronized JavaScriptJob getEarliestJob(final JavaScriptJobFilter filter) {
if (filter == null) {
return scheduledJobsQ_.peek();
}
for (final JavaScriptJob job : scheduledJobsQ_) {
if (filter.passes(job)) {
return job;
}
}
return null;
}
/**
* {@inheritDoc}
*/
@Override
public boolean runSingleJob(final JavaScriptJob givenJob) {
assert givenJob != null;
final JavaScriptJob job = getEarliestJob();
if (job != givenJob) {
return false;
}
final long currentTime = System.currentTimeMillis();
if (job.getTargetExecutionTime() > currentTime) {
return false;
}
synchronized (this) {
if (scheduledJobsQ_.remove(job)) {
currentlyRunningJob_ = job;
}
// no need to notify if processing is started
}
final boolean debug = LOG.isDebugEnabled();
final boolean isPeriodicJob = job.isPeriodic();
if (isPeriodicJob) {
final long jobPeriod = job.getPeriod().longValue();
// reference: http://ejohn.org/blog/how-javascript-timers-work/
long timeDifference = currentTime - job.getTargetExecutionTime();
timeDifference = (timeDifference / jobPeriod) * jobPeriod + jobPeriod;
job.setTargetExecutionTime(job.getTargetExecutionTime() + timeDifference);
// queue
synchronized (this) {
if (!cancelledJobs_.contains(job.getId())) {
if (debug) {
LOG.debug("Reschedulling job " + job);
}
scheduledJobsQ_.add(job);
notify();
}
}
}
if (debug) {
final String periodicJob = isPeriodicJob ? "interval " : "";
LOG.debug("Starting " + periodicJob + "job " + job);
}
try {
job.run();
}
catch (final RuntimeException e) {
LOG.error("Job run failed with unexpected RuntimeException: " + e.getMessage(), e);
}
finally {
synchronized (this) {
if (job == currentlyRunningJob_) {
currentlyRunningJob_ = null;
}
notify();
}
}
if (debug) {
final String periodicJob = isPeriodicJob ? "interval " : "";
LOG.debug("Finished " + periodicJob + "job " + job);
}
return true;
}
/**
* Our own serialization (to handle the weak reference)
* @param in the stream to read form
* @throws IOException in case of error
* @throws ClassNotFoundException in case of error
*/
private void readObject(final ObjectInputStream in) throws IOException, ClassNotFoundException {
in.defaultReadObject();
// we do not store the jobs (at the moment)
scheduledJobsQ_ = new PriorityQueue<>();
cancelledJobs_ = new ArrayList<>();
currentlyRunningJob_ = null;
}
}