| /* |
| * 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 |
| * <p> |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * <p> |
| * 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.hadoop.ozone.recon.scm; |
| |
| import org.hadoop.ozone.recon.schema.tables.daos.ReconTaskStatusDao; |
| import org.hadoop.ozone.recon.schema.tables.pojos.ReconTaskStatus; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| /** |
| * Any background task that keeps SCM's metadata up to date. |
| */ |
| public abstract class ReconScmTask { |
| |
| private static final Logger LOG = LoggerFactory.getLogger(ReconScmTask.class); |
| private Thread taskThread; |
| private ReconTaskStatusDao reconTaskStatusDao; |
| private volatile boolean running; |
| |
| protected ReconScmTask(ReconTaskStatusDao reconTaskStatusDao) { |
| this.reconTaskStatusDao = reconTaskStatusDao; |
| } |
| |
| private void register() { |
| String taskName = getTaskName(); |
| if (!reconTaskStatusDao.existsById(taskName)) { |
| ReconTaskStatus reconTaskStatusRecord = new ReconTaskStatus( |
| taskName, 0L, 0L); |
| reconTaskStatusDao.insert(reconTaskStatusRecord); |
| LOG.info("Registered {} task ", taskName); |
| } |
| } |
| |
| /** |
| * Start underlying start thread. |
| */ |
| public synchronized void start() { |
| register(); |
| if (!isRunning()) { |
| LOG.info("Starting {} Thread.", getTaskName()); |
| running = true; |
| taskThread = new Thread(this::run); |
| taskThread.setName(getTaskName()); |
| taskThread.setDaemon(true); |
| taskThread.start(); |
| } else { |
| LOG.info("{} Thread is already running.", getTaskName()); |
| } |
| } |
| |
| /** |
| * Stop underlying task thread. |
| */ |
| public synchronized void stop() { |
| if (running) { |
| LOG.info("Stopping {} Thread.", getTaskName()); |
| running = false; |
| notifyAll(); |
| } else { |
| LOG.info("{} Thread is not running.", getTaskName()); |
| } |
| } |
| |
| public boolean isRunning() { |
| if (!running) { |
| synchronized (this) { |
| return taskThread != null |
| && taskThread.isAlive(); |
| } |
| } |
| return true; |
| } |
| |
| protected void recordSingleRunCompletion() { |
| reconTaskStatusDao.update(new ReconTaskStatus(getTaskName(), |
| System.currentTimeMillis(), 0L)); |
| } |
| |
| protected boolean canRun() { |
| return running; |
| } |
| |
| public String getTaskName() { |
| return getClass().getSimpleName(); |
| } |
| |
| protected abstract void run(); |
| } |