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Open-source constraint solver.
/**
* Copyright (c) 2016, Ecole des Mines de Nantes
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the .
* 4. Neither the name of the 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 ''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
* DISCLAIMED. IN NO EVENT SHALL 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.
*/
package org.chocosolver.util.iterators;
/**
* An interface to declare range iterator.
*
* A range iterator can be iterated in 2 ways: bottom-up (from lower bound to upper bound)
* and top-down (from upper bound to lower bound).
* To iterate in bottom-up way, first call bottomUpInit(), then hasNext() and next().
* To iterate in bottom-up way, first call topDownInit(), then hasPrevious() and previous().
*
* Once a way is selected, using the wrong methods can lead to unexpected behaviour.
*
*
* RangeIterator rit = ...;
* rit.bottomUpInit();
* while (rit.hasNext()) {
* int from = rit.min();
* int to = rit.max();
* // operate on range [from,to] here
* rit.next();
* }
*
* OR
*
*
* DisposableRangeIterator rit = ...;
* rit.topDownInit();
* while (rit.hasPrevious()) {
* int from = rit.min();
* int to = rit.max();
* // operate on range [from,to] here
* rit.previous();
* }
*
*
* Based on
"Views and Iterators for Generic Constraint Implementations"
* C. Shulte and G. Tack.
* Eleventh International Conference on Principles and Practice of Constraint Programming
*
*
* @author Charles Prud'homme
* @since 05/10/11
*/
public interface RangeIterator {
void bottomUpInit();
void topDownInit();
/**
* Returns true if the iteration has more ranges. (In other
* words, returns true if next would return a valid range.)
*
* @return true if the getIterator has more ranges.
*/
boolean hasNext();
/**
* Returns true if the iteration has more ranges. (In other
* words, returns true if previous would return a valid range.)
*
* @return true if the getIterator has more ranges.
*/
boolean hasPrevious();
/**
* Compute the next range.
*/
void next();
/**
* Compute the previous range.
*/
void previous();
/**
* Return the lower bound of the current range (inclusive)
*
* @return lower bound of the current range
*/
int min();
/**
* Return the upper bound of the current range (inclusive)
*
* @return upper bound of the current range
*/
int max();
}