Synchronization issue in ActiveMQThreadPoolExecutor

@Override
public boolean offer(Runnable runnable) {
  int poolSize = executor.getPoolSize();

  // If the are less threads than the configured maximum, then the tasks is
  // only queued if there are some idle threads that can run that tasks.
  // We have to add the queue size, since some tasks might just have been queued
  // but not yet taken by an idle thread.
  if (poolSize < executor.getMaximumPoolSize() && (size() + executor.getActive()) >= poolSize)
    return false;

  return super.offer(runnable);
}

git clone https://github.com/dudaerich/activemq-artemis
cd activemq-artemis
git checkout ActiveMQThreadPoolExecutorTest

mvn test -Dtest=ActiveMQThreadPoolExecutorTest -Ptests -DfailIfNoTests=false -Drat.ignoreErrors=true 2>&1 | tee log