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 * All rights reserved.
 *
 * 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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 * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
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package org.hsqldb.lib;

Author:
Fred Toussi (fredt@users dot sourceforge.net)
Version:
1.7.2
Since:
1.7.2/**
 *
 * @author Fred Toussi (fredt@users dot sourceforge.net)
 * @version 1.7.2
 * @since 1.7.2
 */
public interface Set extends Collection {

    int size();

    boolean isEmpty();

    boolean contains(Object o);

    Iterator iterator();

/*
    Object[] toArray();

    void toArray(Object a[]);
*/
    boolean add(Object o);

    
This method returns the Object that is already in the set and is
equal to the argument o.
/**
     * This method returns the Object that is already in the set and is
     * equal to the argument o.
     */
    Object get(Object o);

    boolean remove(Object o);

/*
    boolean containsAll(Collection c);
    boolean addAll(Collection c);
    boolean retainAll(Collection c);
    boolean removeAll(Collection c);
*/
    void clear();

    boolean equals(Object o);

    int hashCode();
}