io.druid.indexing.overlord.helpers.OverlordHelperManager Maven / Gradle / Ivy
/*
* Licensed to Metamarkets Group Inc. (Metamarkets) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. Metamarkets 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 io.druid.indexing.overlord.helpers;
import com.google.inject.Inject;
import io.druid.java.util.common.concurrent.ScheduledExecutorFactory;
import io.druid.java.util.common.lifecycle.LifecycleStart;
import io.druid.java.util.common.lifecycle.LifecycleStop;
import io.druid.java.util.common.logger.Logger;
import java.util.Set;
import java.util.concurrent.ScheduledExecutorService;
/**
*/
public class OverlordHelperManager
{
private static final Logger log = new Logger(OverlordHelperManager.class);
private final ScheduledExecutorFactory execFactory;
private final Set helpers;
private volatile ScheduledExecutorService exec;
private final Object startStopLock = new Object();
private volatile boolean started = false;
@Inject
public OverlordHelperManager(
ScheduledExecutorFactory scheduledExecutorFactory,
Set helpers)
{
this.execFactory = scheduledExecutorFactory;
this.helpers = helpers;
}
@LifecycleStart
public void start()
{
synchronized (startStopLock) {
if (!started) {
log.info("OverlordHelperManager is starting.");
for (OverlordHelper helper : helpers) {
if (helper.isEnabled()) {
if (exec == null) {
exec = execFactory.create(1, "Overlord-Helper-Manager-Exec--%d");
}
helper.schedule(exec);
}
}
started = true;
log.info("OverlordHelperManager is started.");
}
}
}
@LifecycleStop
public void stop()
{
synchronized (startStopLock) {
if (started) {
log.info("OverlordHelperManager is stopping.");
if (exec != null) {
exec.shutdownNow();
exec = null;
}
started = false;
log.info("OverlordHelperManager is stopped.");
}
}
}
}