/*
 * Copyright 1998-2014 University Corporation for Atmospheric Research/Unidata
 *
 *   Portions of this software were developed by the Unidata Program at the
 *   University Corporation for Atmospheric Research.
 *
 *   Access and use of this software shall impose the following obligations
 *   and understandings on the user. The user is granted the right, without
 *   any fee or cost, to use, copy, modify, alter, enhance and distribute
 *   this software, and any derivative works thereof, and its supporting
 *   documentation for any purpose whatsoever, provided that this entire
 *   notice appears in all copies of the software, derivative works and
 *   supporting documentation.  Further, UCAR requests that the user credit
 *   UCAR/Unidata in any publications that result from the use of this
 *   software or in any product that includes this software. The names UCAR
 *   and/or Unidata, however, may not be used in any advertising or publicity
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 *   written permission is obtained from UCAR/Unidata. The user also
 *   understands that UCAR/Unidata is not obligated to provide the user with
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 *
 *   THIS SOFTWARE IS PROVIDED BY UCAR/UNIDATA "AS IS" AND ANY EXPRESS OR
 *   IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 *   WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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 *   WITH THE ACCESS, USE OR PERFORMANCE OF THIS SOFTWARE.
 */
package org.meteoinfo.ndarray;

import java.io.IOException;

/**
 * An iterator over StructureData.
  * Make sure that you call finish().
  * Best to put in a try/finally block like:
<pre>
try {
  while (iter.hasNext())
   process(iter.next());
 } finally {
   iter.finish();
 }
</pre>
 * @author caron
 * @since Feb 23, 2008
 */
public interface StructureDataIterator {

  /**
   * See if theres more StructureData in the iteration.
   * You must always call this before calling next().
   *
   * @return true if more records are available
   * @throws IOException on read error
   */
  public boolean hasNext() throws IOException;

  /**
   * Get the next StructureData in the iteration.
   *
   * @return next StructureData record.
   * @throws IOException on read error
   */
  public StructureData next() throws IOException;

  /**
   * Hint to use this much memory in buffering the iteration.
   * No guarentee that it will be used by the implementation.
   *
   * @param bytes amount of memory in bytes
   */
  public void setBufferSize(int bytes);

  /**
   * Start the iteration over again.
   *
   * @return a new or reset iterator.
   */
  public StructureDataIterator reset();

  public int getCurrentRecno();

  /**
   * Make sure that the iterator is complete, and recover resources.
   * Best to put in a try/finally block like:
   * <pre>
 try {
   while (iter.hasNext())
    process(iter.next());
  } finally {
    iter.finish();
  }
   </pre>
   */
  public void finish();

}
