content: /*
   * Copyright (C) 2012-2023 52°North Spatial Information Research GmbH
   *
   * This program is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 as published
   * by the Free Software Foundation.
   *
   * If the program is linked with libraries which are licensed under one of
   * the following licenses, the combination of the program with the linked
   * library is not considered a "derivative work" of the program:
   *
   *     - Apache License, version 2.0
   *     - Apache Software License, version 1.0
   *     - GNU Lesser General Public License, version 3
   *     - Mozilla Public License, versions 1.0, 1.1 and 2.0
   *     - Common Development and Distribution License (CDDL), version 1.0
   *
   * Therefore the distribution of the program linked with libraries licensed
   * under the aforementioned licenses, is permitted by the copyright holders
   * if the distribution is compliant with both the GNU General Public
   * License version 2 and the aforementioned licenses.
   *
   * This program is distributed in the hope that it will be useful, but
   * WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
   * Public License for more details.
   */
  package org.n52.sos.ds.hibernate.util;
  
  import org.hibernate.HibernateException;
  import org.hibernate.ScrollableResults;
  import org.hibernate.Session;
  
  import org.n52.janmayen.AbstractThrowingIterator;
  import org.n52.janmayen.ThrowingIterator;
  import org.n52.janmayen.function.ThrowingFunction;
  
  import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
  
  /**
   * {@code ThrowingIterator}-Wrapper for {@link ScrollableResults}. This class implements {@link AutoCloseable} and will
   * close the {@code ScrollableResults} as well as the unterlying {@link Session}.
   *
   * @param <T> the iterators value type
   * @param <X> the exception type
   *
   * @author Christian Autermann
   *
   */
  @SuppressFBWarnings({"EI_EXPOSE_REP2"})
  public class ThrowingScrollableResultsIterator<T, X extends Exception> extends AbstractThrowingIterator<T, X>
          implements ThrowingIterator<T, X>, AutoCloseable {
  
      private final ScrollableResults results;
      private final Session session;
      private final ThrowingFunction<ScrollableResults, T, X> extractor;
  
      /**
       * Create a new {@code ThrowingScrollableResultsIterator}.
       *
       * @param results   the results
       * @param session   the session
       * @param extractor the extractor
       */
      public ThrowingScrollableResultsIterator(ScrollableResults results, Session session,
                                               ThrowingFunction<ScrollableResults, T, X> extractor) {
          this.results = results;
          this.session = session;
          this.extractor = extractor;
      }
  
      @Override
      public void close() throws HibernateException {
          if (this.session.isOpen()) {
              this.session.close();
          }
      }
  
      @Override
      protected T computeNext() throws X {
          if (this.results.next()) {
              return this.extractor.apply(this.results);
          } else {
              close();
              return endOfData();
          }
      }
  
  }
  