DefaultOptimizeScheduler.java

package proj.zoie.api.indexing;

/**
 * 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
 *
 *     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.
 */
import java.util.Calendar;
import java.util.Date;
import java.util.Timer;
import java.util.TimerTask;

public class DefaultOptimizeScheduler extends OptimizeScheduler {
  private static long DAY_IN_MILLIS = 1000L * 60L * 60L * 24L;
  private long _optimizeDuration;

  private volatile boolean _optimizeScheduled;
  private final OptimizeType _optimizeType;

  private final Timer _optimizeTimer;
  private TimerTask _currentOptimizationTimerTask;
  private Date _dateToStartOptimize;

  private class OptimizeTimerTask extends TimerTask {
    @Override
    public void run() {
      _optimizeScheduled = true;
    }
  }

  // calculate to run next day at 1am
  private static Date calculateNextDay() {
    Calendar cal = Calendar.getInstance();
    int curHour = cal.get(Calendar.HOUR_OF_DAY);
    cal.set(Calendar.HOUR_OF_DAY, 1);
    cal.set(Calendar.MINUTE, 0);
    cal.set(Calendar.SECOND, 0);
    cal.set(Calendar.MILLISECOND, 0);
    if (curHour > 1) {
      cal.set(Calendar.DAY_OF_YEAR, cal.get(Calendar.DAY_OF_YEAR) + 1);
    }
    return cal.getTime();
  }

  public DefaultOptimizeScheduler() {
    _optimizeDuration = DAY_IN_MILLIS;
    _optimizeScheduled = false;
    _dateToStartOptimize = calculateNextDay();
    _currentOptimizationTimerTask = new OptimizeTimerTask();
    _optimizeTimer = new Timer("index optimization timer", true);
    _optimizeTimer.scheduleAtFixedRate(_currentOptimizationTimerTask, _dateToStartOptimize,
      _optimizeDuration);
    _optimizeType = OptimizeType.PARTIAL;
  }

  public long getOptimizeDuration() {
    return _optimizeDuration;
  }

  public synchronized void setOptimizeDuration(long optimizeDuration) {
    if (_optimizeDuration != optimizeDuration) {
      _currentOptimizationTimerTask.cancel();
      _optimizeTimer.purge();
      _currentOptimizationTimerTask = new OptimizeTimerTask();
      _optimizeTimer.scheduleAtFixedRate(_currentOptimizationTimerTask, _dateToStartOptimize,
        optimizeDuration);
      _optimizeDuration = optimizeDuration;
    }
  }

  public synchronized void setDateToStartOptimize(Date optimizeStartDate) {
    if (!_dateToStartOptimize.equals(optimizeStartDate)) {
      _currentOptimizationTimerTask.cancel();
      _optimizeTimer.purge();
      _currentOptimizationTimerTask = new OptimizeTimerTask();
      _optimizeTimer.scheduleAtFixedRate(_currentOptimizationTimerTask, optimizeStartDate,
        _optimizeDuration);
      _dateToStartOptimize = optimizeStartDate;
    }
  }

  public Date getDateToStartOptimize() {
    return _dateToStartOptimize;
  }

  public OptimizeType getOptimizeType() {
    return _optimizeType;
  }

  @Override
  public OptimizeType getScheduledOptimizeType() {
    return (_optimizeScheduled ? _optimizeType : OptimizeType.NONE);
  }

  @Override
  public void finished() {
    _optimizeScheduled = false;
  }

  @Override
  public void shutdown() {
    _optimizeTimer.cancel();
    _optimizeTimer.purge();
  }
}