common/src/main/java/org/apache/drill/common/SelfCleaningRunnable.java

/*
 * 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.drill.common;

/**
 * A wrapper for Runnables that provides a hook to do cleanup.
 */
public abstract class SelfCleaningRunnable implements Runnable {
  private final Runnable runnable;

  /**
   * Constructor.
   *
   * @param runnable the Runnable to wrap
   */
  public SelfCleaningRunnable(final Runnable runnable) {
    this.runnable = runnable;
  }

  @Override
  public void run() {
    try {
      runnable.run();
    } finally {
      cleanup();
    }
  }

  /**
   * Cleanup.
   *
   * <p>Derived classes should put any necessary cleanup in here. This
   * is guaranteed to be called, even if the wrapped Runnable throws an
   * exception.
   */
  protected abstract void cleanup();
}