Class ChessSquare

java.lang.Object

ChessSquare

public class ChessSquare
extends Object

A class that represents a square on a chessboard. A square has a coordinate and possibly a chesspiece.

See the test web page for a description of how the coordinates of a square on a chessboard is defined, as well as the letters used to represent the different chess pieces.

Constructor Summary

Constructors

Constructor	Description
ChessSquare()	Initializes this square to have the coordinates a1 and to have no piece occupying the square.
ChessSquare(ChessSquare other)	Initializes this square by copying the coordinates and the occupying piece from another square.
ChessSquare(String file, String rank, String piece)	Initializes this square to have the coordinates given by the specified file and rank, and to be occupied by the specified piece.

Method Summary

Modifier and Type	Method	Description
boolean	areConnected(ChessSquare other)	Returns true if and only if this square is connected to the specified square by a straight line path.
boolean	equals(Object obj)	Compares this square to an object for equality.
String	file()	Returns the file of this square as a string.
int	hashCode()	Returns a hash code for this square.
boolean	isAdjacentTo(ChessSquare other)	Returns true if and only if this square is adjacent to the specified square.
String	piece()	Returns the piece occupying this square.
String	rank()	Returns the rank of this square as a string.

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ChessSquare

public ChessSquare()

Initializes this square to have the coordinates a1 and to have no piece occupying the square.

ChessSquare

public ChessSquare(String file,
                   String rank,
                   String piece)

Initializes this square to have the coordinates given by the specified file and rank, and to be occupied by the specified piece.

If piece is the empty string then no piece is on the square.

Parameters:

file - the file of the square

rank - the rank of the square

piece - the piece on the square

Throws:

IllegalArgumentException - if file or rank are not strings of length 1

IllegalArgumentException - if piece is not empty and not a string of length 1

IllegalArgumentException - if file is not a valid file

IllegalArgumentException - if rank is not a valid rank

IllegalArgumentException - if piece is not a valid piece

ChessSquare

public ChessSquare(ChessSquare other)

Initializes this square by copying the coordinates and the occupying piece from another square.

Parameters:

other - the object to copy

Method Detail

file

public String file()

Returns the file of this square as a string. The returned string is a string of length 1 and is equal to a lowercase letter between a and h, inclusive.

Returns:

the file of this square

rank

public String rank()

Returns the rank of this square as a string. The returned string is a string of length 1 and is equal to a digit between 1 and 8, inclusive.

Returns:

the rank of this square

piece

public String piece()

Returns the piece occupying this square. The returned string is a string of length 1 and is equal to one of "K", "Q", "R", "B", "N", "P", or the empty string. The empty string is used to indicate no piece is on the square.

Returns:

the piece occupying this square

isAdjacentTo

public boolean isAdjacentTo(ChessSquare other)

Returns true if and only if this square is adjacent to the specified square. Two squares are adjacent if they are within one square of each other horizontally, vertically, or diagonally.

Parameters:

other - the square to compare

Returns:

true if and only if this square is adjacent to the specified square

areConnected

public boolean areConnected(ChessSquare other)

Returns true if and only if this square is connected to the specified square by a straight line path. A straight line path is a linear path that is either horizontal, vertical, or on a +/- 45 degree diagonal.

Parameters:

other - the square to check

Returns:

true if and only if this square is connected to the specified square by a straight line path

equals

public boolean equals(Object obj)

Compares this square to an object for equality. Returns true if and only if obj is a ChessSquare instance having the same rank and file as this square. The occupying piece is not considered in this method.

Overrides:

equals in class Object

Parameters:

obj - the object to compare

Returns:

true if and only obj is a ChessSquare instance having the same rank and file as this square

hashCode

public int hashCode()

Returns a hash code for this square.

Squares that are not equal should return different hash codes in most cases.

Overrides:

hashCode in class Object

Returns:

a hash code for this square