/**
 * ============LICENSE_START=======================================================
 * org.onap.aai
 * ================================================================================
 * Copyright © 2017 AT&T Intellectual Property. All rights reserved.
 * Copyright © 2017 Amdocs
 * ================================================================================
 * 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.
 * ============LICENSE_END=========================================================
 *
 * ECOMP is a trademark and service mark of AT&T Intellectual Property.
 */
package org.onap.aai.datarouter.util;

import java.io.File;
import java.util.TimerTask;

public abstract class FileWatcher extends TimerTask {
  private long timeStamp;
  private File file;

  public FileWatcher(File file) {
    this.file = file;
    this.timeStamp = file.lastModified();
  }

  @Override
  public final void run() {
    long newTimeStamp = file.lastModified();

    if ((newTimeStamp - this.timeStamp) > 500) {
      this.timeStamp = newTimeStamp;
      onChange(file);
    }
  }
  
  protected abstract void onChange(File file);
}