org.chocosolver.util.iterators

Interface RangeIterator

All Known Implementing Classes:

DisposableRangeBoundIterator, DisposableRangeIterator

public interface RangeIterator

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

Since:

05/10/11

Author:

Charles Prud'homme

Method Summary

Methods

Modifier and Type	Method and Description
void	bottomUpInit()
boolean	hasNext() Returns true if the iteration has more ranges.
boolean	hasPrevious() Returns true if the iteration has more ranges.
int	max() Return the upper bound of the current range (inclusive)
int	min() Return the lower bound of the current range (inclusive)
void	next() Compute the next range.
void	previous() Compute the previous range.
void	topDownInit()

Method Detail

bottomUpInit

void bottomUpInit()

topDownInit

void topDownInit()

hasNext

boolean hasNext()

Returns true if the iteration has more ranges. (In other words, returns true if next would return a valid range.)

Returns:

true if the getIterator has more ranges.

hasPrevious

boolean hasPrevious()

Returns true if the iteration has more ranges. (In other words, returns true if previous would return a valid range.)

Returns:

true if the getIterator has more ranges.

next

void next()

Compute the next range.

previous

void previous()

Compute the previous range.

min

int min()

Return the lower bound of the current range (inclusive)

Returns:

lower bound of the current range

max

int max()

Return the upper bound of the current range (inclusive)

Returns:

upper bound of the current range