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.calcite.util;
  
  import java.io.IOException;
  import java.util.ArrayList;
  import java.util.List;
  
  /** Helper that holds onto {@link AutoCloseable} resources and releases them
   * when its {@code #close} method is called.
   *
   * <p>Similar to {@code com.google.common.io.Closer} but can deal with
   * {@link AutoCloseable}, and doesn't throw {@link IOException}. */
  public final class Closer implements AutoCloseable {
    private final List<AutoCloseable> list = new ArrayList<>();
  
    /** Registers a resource. */
    public <E extends AutoCloseable> E add(E e) {
      list.add(e);
      return e;
    }
  
    @Override public void close() {
      for (AutoCloseable closeable : list) {
        try {
          closeable.close();
        } catch (RuntimeException e) {
          throw e;
        } catch (Exception e) {
          throw new RuntimeException(e);
        }
      }
    }
  }
  