GracefulExecutorShutdown.java

/*
 * Copyright [2014] [Christian Loehnert, krampenschiesser@gmail.com]
 * 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.
 */
package de.ks.activity.executor;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.concurrent.ExecutorService;
import java.util.concurrent.TimeUnit;

public class GracefulExecutorShutdown {
  private static final Logger log = LoggerFactory.getLogger(GracefulExecutorShutdown.class);

  public void shutdown(ExecutorService executor, String identifier) {
    if (!executor.isShutdown()) {
      log.debug("Shutting down executor {}", identifier);
      executor.shutdown();

      if (!awaitTermination(executor)) {
        executor.shutdownNow();
        if (!awaitTermination(executor)) {
          log.warn("Could not stop executor service {}", identifier);
        }
      }
    }
  }

  protected boolean awaitTermination(ExecutorService executor) {
    boolean stopped = false;
    try {
      stopped = executor.awaitTermination(5, TimeUnit.SECONDS);
    } catch (InterruptedException e) {
      stopped = true;
      //
    }
    return stopped;
  }
}