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 * All rights reserved.
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 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * Neither the name of the HSQL Development Group nor the names of its
 * contributors may be used to endorse or promote products derived from this
 * software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
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package org.hsqldb.navigator;

import org.hsqldb.Row;

/**
 *
 * @author Fred Toussi (fredt@users dot sourceforge.net)
 * @version 2.5.1
 * @since 1.7.2
 */
public interface RowIterator {

    RowIterator emptyRowIterator = new EmptyRowIterator();

    Object getField(int col);

    boolean next();

    Row getCurrentRow();

    Object[] getCurrent();

    void removeCurrent();

    void release();

    long getRowId();

    final class EmptyRowIterator implements RowIterator {

        private EmptyRowIterator() {}

        public Object getField(int col) {
            return null;
        }

        public boolean next() {
            return false;
        }

        public Row getCurrentRow() {
            return null;
        }

        public Object[] getCurrent() {
            return null;
        }

        public void release() {}

        public void removeCurrent() {}

        public long getRowId() {
            return 0L;
        }
    }
}
