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Provides a single jar containing all JAITools modules which you can use instead of including individual modules in your project. Note: It does not include the Jiffle scripting language or Jiffle image operator.

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/* ====================================================================
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 2001-2004 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. 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.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowledgement:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowledgement may appear in the software itself,
 *    if and wherever such third-party acknowledgements normally appear.
 *
 * 4. The names "The Jakarta Project", "Commons", and "Apache Software
 *    Foundation" must not be used to endorse or promote products derived
 *    from this software without prior written permission. For written
 *    permission, please contact [email protected].
 *
 * 5. Products derived from this software may not be called "Apache"
 *    nor may "Apache" appear in their names without prior written
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 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * .
 */
package org.apache.commons.collections;

/**
 * Defines a collection for priority queues, which can insert, peek and pop.
 * 
 * This interface is now replaced by the Buffer interface.
 *
 * @deprecated Replaced by the Buffer interface and implementations in buffer subpackage.
 *  Due to be removed in v4.0.
 * @since Commons Collections 1.0
 * @version $Revision: 1.13 $ $Date: 2004/01/14 21:43:04 $
 * 
 * @author Peter Donald
 */
public interface PriorityQueue {
    
    /**
     * Clear all elements from queue.
     */
    void clear();

    /**
     * Test if queue is empty.
     *
     * @return true if queue is empty else false.
     */
    boolean isEmpty();

    /**
     * Insert an element into queue.
     *
     * @param element the element to be inserted
     *
     * @throws ClassCastException if the specified element's
     * type prevents it from being compared to other items in the queue to
     * determine its relative priority.  
     */
    void insert(Object element);

    /**
     * Return element on top of heap but don't remove it.
     *
     * @return the element at top of heap
     * @throws java.util.NoSuchElementException if isEmpty() == true
     */
    Object peek();

    /**
     * Return element on top of heap and remove it.
     *
     * @return the element at top of heap
     * @throws java.util.NoSuchElementException if isEmpty() == true
     */
    Object pop();
    
}