Example #1
0
 private int getScoreForEndPosition(Player player) {
   int returnValue = -1;
   if (player.isInStaleMate() || itsBoard.isThirdOccuranceOfPosition()) returnValue = 500;
   else if (player.isInCheckMate()) {
     if (player == itsPlayer) returnValue = 0;
     else returnValue = 1000;
   }
   return returnValue;
 }
Example #2
0
 public void search(ChessBoard board, Player player) {
   itsTable = new PositionHashTable();
   itsMoves.clear();
   itsPlayer = player;
   itsBoard = board;
   Collection moves = getAllMoves(player);
   for (Iterator i = moves.iterator(); i.hasNext(); ) {
     AbstractMove move = (AbstractMove) i.next();
     move.getPiece().findMoves_safe();
     move = player.movePiece(move);
     itsBoard.recordPosition();
     String positionCode = itsBoard.getPositionCode() + player.getColor();
     int score = examineMove(move, player, itsSearchQuality, positionCode);
     move.setScore(score);
     itsMoves.add(move);
     itsBoard.removeLastPosition();
     player.reverseMove(move);
   }
 }
Example #3
0
 private Collection getAllMoves(Player player) {
   Collection moves = new HashSet();
   for (Iterator p = player.getPieces().iterator(); p.hasNext(); ) {
     Piece piece = (Piece) p.next();
     SquareInterface startSquare = piece.getLocation();
     for (Iterator s = piece.getMoveOptions().iterator(); s.hasNext(); ) {
       SquareInterface square = (SquareInterface) s.next();
       moves.add(new Move(piece, startSquare, square));
     }
   }
   return moves;
 }
Example #4
0
 private int examineMove(AbstractMove theMove, Player player, int depth, String position) {
   Player player2 = player.getOpponent();
   player2.findAllMoves(theMove.isCheck());
   int endPositionScore = getScoreForEndPosition(player2);
   if (endPositionScore != -1) {
     itsTable.add(position, endPositionScore);
     return endPositionScore;
   } else if (depth == 1) {
     int score = itsScorer.getScore(itsBoard, itsPlayer);
     itsTable.add(position, score);
     return score;
   } else {
     int bestScore = 1234;
     Collection moves = getAllMoves(player2);
     for (Iterator i = moves.iterator(); i.hasNext(); ) {
       AbstractMove move = (AbstractMove) i.next();
       move.getPiece().findMoves_safe();
       move = player2.movePiece(move);
       String newPosition = itsBoard.getPositionCode() + player2.getColor();
       int thisScore = -321;
       boolean hasIt = itsTable.has(newPosition);
       if (hasIt) {
         thisScore = itsTable.getScore();
       } else {
         thisScore = examineMove(move, player2, depth - 1, newPosition);
         itsTable.add(newPosition, thisScore);
       }
       bestScore = compareScores(player2, bestScore, thisScore);
       player2.reverseMove(move);
     }
     return bestScore;
   }
 }