/* 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.activiti.engine.impl.asyncexecutor;
import java.util.concurrent.atomic.AtomicBoolean;
import org.activiti.engine.ActivitiOptimisticLockingException;
import org.activiti.engine.impl.cmd.AcquireAsyncJobsDueCmd;
import org.activiti.engine.impl.interceptor.CommandExecutor;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
*
* @author Tijs Rademakers
*/
public class AcquireAsyncJobsDueRunnable implements Runnable {
private static Logger log = LoggerFactory.getLogger(AcquireAsyncJobsDueRunnable.class);
protected final AsyncExecutor asyncExecutor;
protected volatile boolean isInterrupted = false;
protected final Object MONITOR = new Object();
protected final AtomicBoolean isWaiting = new AtomicBoolean(false);
protected long millisToWait = 0;
public AcquireAsyncJobsDueRunnable(AsyncExecutor asyncExecutor) {
this.asyncExecutor = asyncExecutor;
}
public synchronized void run() {
log.info("{} starting to acquire async jobs due");
final CommandExecutor commandExecutor = asyncExecutor.getCommandExecutor();
while (!isInterrupted) {
try {
AcquiredJobEntities acquiredJobs = commandExecutor.execute(new AcquireAsyncJobsDueCmd(asyncExecutor));
// if all jobs were executed
millisToWait = asyncExecutor.getDefaultAsyncJobAcquireWaitTimeInMillis();
int jobsAcquired = acquiredJobs.size();
if (jobsAcquired >= asyncExecutor.getMaxAsyncJobsDuePerAcquisition()) {
millisToWait = 0;
}
} catch (ActivitiOptimisticLockingException optimisticLockingException) {
if (log.isDebugEnabled()) {
log.debug("Optimistic locking exception during async job acquisition. If you have multiple async executors running against the same database, " +
"this exception means that this thread tried to acquire a due async job, which already was acquired by another async executor acquisition thread." +
"This is expected behavior in a clustered environment. " +
"You can ignore this message if you indeed have multiple async executor acquisition threads running against the same database. " +
"Exception message: {}", optimisticLockingException.getMessage());
}
} catch (Throwable e) {
log.error("exception during async job acquisition: {}", e.getMessage(), e);
millisToWait = asyncExecutor.getDefaultAsyncJobAcquireWaitTimeInMillis();
}
if (millisToWait > 0) {
try {
if (log.isDebugEnabled()) {
log.debug("async job acquisition thread sleeping for {} millis", millisToWait);
}
synchronized (MONITOR) {
if(!isInterrupted) {
isWaiting.set(true);
MONITOR.wait(millisToWait);
}
}
if (log.isDebugEnabled()) {
log.debug("async job acquisition thread woke up");
}
} catch (InterruptedException e) {
if (log.isDebugEnabled()) {
log.debug("async job acquisition wait interrupted");
}
} finally {
isWaiting.set(false);
}
}
}
log.info("{} stopped async job due acquisition");
}
public void stop() {
synchronized (MONITOR) {
isInterrupted = true;
if(isWaiting.compareAndSet(true, false)) {
MONITOR.notifyAll();
}
}
}
public long getMillisToWait() {
return millisToWait;
}
public void setMillisToWait(long millisToWait) {
this.millisToWait = millisToWait;
}
}