Pawn.java

/**
* Bishop.java
*
* @author Deep Patel
*
* REMARKS: This is a class which stores information about the pawn
* piece and how it moves, which is one square at a time in the forward direction,
* and can move diagonally one square to capture a piece. It also has a method for pawn promotion
* which occurs when the pawn reaches the other side of the board so that the user can promote
* it to a new piece
*/

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Pawn extends Piece {
    //Instance Variables
    private boolean turn;
    
    //Constructor
    public Pawn(boolean myPiece) {
        super(myPiece);
    }

     /**
   * This method is used to check if the move made by the pawn piece is a valid
   * move for the piece 
   *
   * Parameters:
   * Board board - The method take in the current state of the board to validate the move
   * Move move - The method takes in the move being made
   *
   * Returns a boolean to indicate whether the move was valid
   */
    public boolean isValidMove(Board board, Move move) {
        int direction;
        if (turn) {
            direction = -1;
        } else {
            direction = 1;
        }
        if (move.getToCol() == move.getFromCol()) { // Moving straight
            if (move.getToRow() - move.getFromRow() == direction) {
                return board.getSymbol(move.getToRow() - 1, move.getToCol() - 1) == ' '; // if destination is empty
            }
        } else if (Math.abs(move.getToCol() - move.getFromCol()) == 1
                && move.getToRow() - move.getFromRow() == direction) { // Capturing diagonally
            return Character.isUpperCase(board.getSymbol(move.getToRow() - 1, move.getToCol() - 1)) != turn; // if capturing opponent's piece
        }
        return false;
    }

    //Set turn to whose turn it is 
    public void setTurn(boolean t) {
        turn = t;
    }

     /**
   * This method is used to promote a pawn once it reaches the other side of the board. It prompts the
   * user to pick a new piece to promote the pawn to
   *
   * Returns an int of the piece you want to promote to
   */
    public int promotePawn() {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        String s;
        int choice = -1;
        
        System.out.println(
            "Your pawn is ready to promote.  Please enter the desired type of piece: 0 for Queen, 1 for Bishop, 2 for Rook, 3 for Knight");
        try {
            s = br.readLine();
            choice = Integer.parseInt(s);
        } catch (IOException e) {
            System.out.println("Error"); 
        }        
        if (turn) {
            if (choice < 0 || choice > 3) {
                System.out.println("Enter valid number for promotion: ");
                choice = promotePawn();
            }
        } else {

        }
        return choice;
    }

}