chesspresso.position
Class AbstractPosition

java.lang.Object
  |
  +--chesspresso.position.AbstractPosition

All Implemented Interfaces:

ImmutablePosition

Direct Known Subclasses:

AbstractMutablePosition, CompactPosition

public abstract class AbstractPosition

extends java.lang.Object

implements ImmutablePosition

Version:

$Revision: 1.1 $

Author:

Bernhard Seybold

Field Summary

protected static long	HASH_ALL_MASK
protected static long	HASH_TOPLAY_MASK
protected static long	HASH_TOPLAY_MULT
protected static long[]	s_hashCastleMod
protected static long[]	s_hashEPMod
protected static long[][]	s_hashMod

Fields inherited from interface chesspresso.position.ImmutablePosition

ALL_CASTLES, BLACK_CASTLE, BLACK_LONG_CASTLE, BLACK_SHORT_CASTLE, NO_CASTLES, WHITE_CASTLE, WHITE_LONG_CASTLE, WHITE_SHORT_CASTLE

Constructor Summary

AbstractPosition()

Method Summary

boolean	equals(java.lang.Object obj)
java.lang.String	getFEN() Return the FEN representation of the current position FEN
long	getHashCode() Returns a 64bit hash code of the current position. 64bit should be enough to disnstinguish positions with almost no collisions.
protected static long	getStartPositionHashCode()
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	isCastlePossible(int castle)
boolean	isLegal() Return whether the current position is legal.
boolean	isSquarePossibleEPSquare(int sqi)
boolean	isStartPosition() Returns whether the represented position is the startposition
static boolean	isWhiteToPlay(long hashCode)
java.lang.String	toString()
void	validate() Validates the internal state.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface chesspresso.position.ImmutablePosition

getCastles, getHalfMoveClock, getPlyNumber, getSqiEP, getStone, getToPlay

Field Detail

HASH_ALL_MASK

protected static long HASH_ALL_MASK

HASH_TOPLAY_MASK

protected static long HASH_TOPLAY_MASK

HASH_TOPLAY_MULT

protected static long HASH_TOPLAY_MULT

s_hashMod

protected static long[][] s_hashMod

s_hashCastleMod

protected static long[] s_hashCastleMod

s_hashEPMod

protected static long[] s_hashEPMod

Constructor Detail

AbstractPosition

public AbstractPosition()

Method Detail

getStartPositionHashCode

protected static long getStartPositionHashCode()

isWhiteToPlay

public static boolean isWhiteToPlay(long hashCode)

getHashCode

public long getHashCode()

Description copied from interface: ImmutablePosition

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

Specified by:

getHashCode in interface ImmutablePosition

Returns:

a 64bit hash code

hashCode

public final int hashCode()

Description copied from interface: ImmutablePosition

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

Specified by:

hashCode in interface ImmutablePosition

Overrides:

hashCode in class java.lang.Object

Returns:

a 32bit hash code

isStartPosition

public final boolean isStartPosition()

Description copied from interface: ImmutablePosition

Returns whether the represented position is the startposition

Specified by:

isStartPosition in interface ImmutablePosition

Returns:

whether the represented position is the startposition

equals

public boolean equals(java.lang.Object obj)

Overrides:

equals in class java.lang.Object

getFEN

public java.lang.String getFEN()

Description copied from interface: ImmutablePosition

Return the FEN representation of the current position FEN

Specified by:

getFEN in interface ImmutablePosition

Returns:

the FEN representation of the current position

isCastlePossible

public boolean isCastlePossible(int castle)

isSquarePossibleEPSquare

public boolean isSquarePossibleEPSquare(int sqi)

isLegal

public boolean isLegal()

Description copied from interface: ImmutablePosition

Return whether the current position is legal.

Specified by:

isLegal in interface ImmutablePosition

Returns:

whether the current position is legal

validate

public void validate()
              throws IllegalPositionException

Description copied from interface: ImmutablePosition

Validates the internal state. Used for debugging and testing.

Specified by:

validate in interface ImmutablePosition

Throws:

IllegalPositionException - if the internal state is illegal

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object