content: /*
   * 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.
   */
  package org.apache.kafka.server.util.timer;
  
  public abstract class TimerTask implements Runnable {
      private volatile TimerTaskEntry timerTaskEntry;
      // timestamp in millisecond
      public final long delayMs;
  
      public TimerTask(long delayMs) {
          this.delayMs = delayMs;
      }
  
      public void cancel() {
          synchronized (this) {
              if (timerTaskEntry != null) timerTaskEntry.remove();
              timerTaskEntry = null;
          }
      }
  
      public boolean isCancelled() {
          return timerTaskEntry == null;
      }
  
      final void setTimerTaskEntry(TimerTaskEntry entry) {
          synchronized (this) {
              // if this timerTask is already held by an existing timer task entry,
              // we will remove such an entry first.
              if (timerTaskEntry != null && timerTaskEntry != entry) {
                  timerTaskEntry.remove();
              }
  
              timerTaskEntry = entry;
          }
      }
  
      TimerTaskEntry getTimerTaskEntry() {
          return timerTaskEntry;
      }
  }
  