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/*
 * Copyright (c) 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016 David Berkman
 * 
 * This file is part of the SmallMind Code Project.
 * 
 * The SmallMind Code Project is free software, you can redistribute
 * it and/or modify it under either, at your discretion...
 * 
 * 1) The terms of GNU Affero General Public License as published by the
 * Free Software Foundation, either version 3 of the License, or (at
 * your option) any later version.
 * 
 * ...or...
 * 
 * 2) The terms of the Apache License, Version 2.0.
 * 
 * The SmallMind Code Project 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 or Apache License for more details.
 * 
 * You should have received a copy of the GNU Affero General Public License
 * and the Apache License along with the SmallMind Code Project. If not, see
 *  or .
 * 
 * Additional permission under the GNU Affero GPL version 3 section 7
 * ------------------------------------------------------------------
 * If you modify this Program, or any covered work, by linking or
 * combining it with other code, such other code is not for that reason
 * alone subject to any of the requirements of the GNU Affero GPL
 * version 3.
 */
package org.smallmind.persistence.orm.hibernate;

import java.util.Iterator;
import java.util.NoSuchElementException;
import org.hibernate.ScrollableResults;

public class ScrollIterable implements Iterable {

  private final ScrollableResults scrollableResults;
  private final Class managedClass;

  public ScrollIterable (ScrollableResults scrollableResults, Class managedClass) {

    this.scrollableResults = scrollableResults;
    this.managedClass = managedClass;
  }

  public Iterator iterator () {

    return new ScrollIterator();
  }

  private class ScrollIterator implements Iterator {

    private boolean more;

    public ScrollIterator () {

      more = scrollableResults.first();
    }

    public boolean hasNext () {

      return more;
    }

    public T next () {

      if (!more) {
        throw new NoSuchElementException();
      }

      try {

        Object[] result;

        return managedClass.cast((managedClass.isArray() && ((result = scrollableResults.get()).length > 1)) ? result : scrollableResults.get(0));
      } finally {
        more = scrollableResults.next();
      }
    }

    public void remove () {

      throw new UnsupportedOperationException();
    }
  }
}