vivi-exercises/chess/pieces/Knight.java

package de.vivi.chess.pieces;

import de.vivi.chess.board.Board;
import de.vivi.chess.board.Field;

public class Knight extends Piece {
    public Knight(Color color, Type type) {
        super(color, type);
    }

    public Knight(Color color, Type type, Field field) {
        super(color, type, field);
    }

    @Override
    public char getSymbol() {
        if (getColor() == Color.WHITE) {
            if (getType() == Type.KNIGHT) {
                symbol = '\u265E';
            }

        } else if (getColor() == Color.BLACK) {
            if (getType() == Type.KNIGHT) {
                symbol = '\u2658';
            }
        }
        return symbol;
    }


    @Override
    public boolean isValidMove(Board board, Field from, Field to) {
        if (to.equals(from)) {
            return false;
        }

        int rowDiff = Math.abs(from.getRow() - to.getRow());
        int colDiff = Math.abs(from.getColumn() - to.getColumn());

        boolean isValidLMove = (rowDiff == 2 && colDiff == 1) || (rowDiff == 1 && colDiff == 2);

        if (!isValidLMove) {
            return false;
        }

        Piece targetPiece = board.getPiece(to);
        if (targetPiece == null) {
            return true;
        } else {
            return targetPiece.getColor() != this.getColor();
        }
    }
}