chesspresso.position
Interface ImmutablePosition

All Known Subinterfaces:

MoveablePosition, MutablePosition

All Known Implementing Classes:

AbstractMoveablePosition, AbstractMutablePosition, AbstractPosition

public interface ImmutablePosition

Version:

$Revision: 1.1 $

Author:

Bernhard Seybold

Field Summary

static int	ALL_CASTLES
static int	BLACK_CASTLE
static int	BLACK_LONG_CASTLE
static int	BLACK_SHORT_CASTLE
static int	NO_CASTLES
static int	WHITE_CASTLE
static int	WHITE_LONG_CASTLE
static int	WHITE_SHORT_CASTLE

Method Summary

int	getCastles() Return the still allowed castles as mask.
java.lang.String	getFEN() Return the FEN representation of the current position FEN
int	getHalfMoveClock() Return the number of moves since the last capture and the last pawn move.
long	getHashCode() Returns a 64bit hash code of the current position. 64bit should be enough to disnstinguish positions with almost no collisions.
int	getPlyNumber() Return the current ply number.
int	getSqiEP() Return the current en passant square.
int	getStone(int sqi) Return the stone currently on the given square.
int	getToPlay() Return the player whose turn it is.
int	hashCode() Returns a 32bit hash code of the current position. 32 bit is not enough to distinguish positions reliably, use only if collisions are handled.
boolean	isLegal() Return whether the current position is legal.
boolean	isStartPosition() Returns whether the represented position is the startposition
void	validate() Validates the internal state.

Field Detail

NO_CASTLES

public static final int NO_CASTLES

See Also:

Constant Field Values

WHITE_LONG_CASTLE

public static final int WHITE_LONG_CASTLE

See Also:

Constant Field Values

WHITE_SHORT_CASTLE

public static final int WHITE_SHORT_CASTLE

See Also:

Constant Field Values

BLACK_LONG_CASTLE

public static final int BLACK_LONG_CASTLE

See Also:

Constant Field Values

BLACK_SHORT_CASTLE

public static final int BLACK_SHORT_CASTLE

See Also:

Constant Field Values

WHITE_CASTLE

public static final int WHITE_CASTLE

See Also:

Constant Field Values

BLACK_CASTLE

public static final int BLACK_CASTLE

See Also:

Constant Field Values

ALL_CASTLES

public static final int ALL_CASTLES

See Also:

Constant Field Values

Method Detail

getStone

public int getStone(int sqi)

Return the stone currently on the given square.

Parameters:

sqi - the square

Returns:

the stone of the given square

getSqiEP

public int getSqiEP()

Return the current en passant square.

Returns:

the current en passant square, NO_SQUARE if none

getCastles

public int getCastles()

Return the still allowed castles as mask.

Returns:

the still allowed castles as mask.

getToPlay

public int getToPlay()

Return the player whose turn it is.

Returns:

the player whose turn it is

getPlyNumber

public int getPlyNumber()

Return the current ply number.

Returns:

the current ply number, starting at play no. 0

getHalfMoveClock

public int getHalfMoveClock()

Return the number of moves since the last capture and the last pawn move. This number is used for the 50-move rule.

Returns:

the number of moves since the last capture and the last pawn move

isLegal

public boolean isLegal()

Return whether the current position is legal.

Returns:

whether the current position is legal

getFEN

public java.lang.String getFEN()

Return the FEN representation of the current position FEN

Returns:

the FEN representation of the current position

isStartPosition

public boolean isStartPosition()

Returns whether the represented position is the startposition

Returns:

whether the represented position is the startposition

getHashCode

public long getHashCode()

Returns a 64bit hash code of the current position. 64bit should be enough to disnstinguish positions with almost no collisions. TODO: add reference to paper

Returns:

a 64bit hash code

hashCode

public int hashCode()

Returns a 32bit hash code of the current position. 32 bit is not enough to distinguish positions reliably, use only if collisions are handled.

Overrides:

hashCode in class java.lang.Object

Returns:

a 32bit hash code

validate

public void validate()
              throws IllegalPositionException

Validates the internal state. Used for debugging and testing.

Throws:

IllegalPositionException - if the internal state is illegal