我正在尝试创建一个国际象棋程序，但是每当我尝试迈出第一步时，我都必须先单击每个棋子，然后才能获得可以移动的棋子。我有部分代码会导致错误以及错误本身。
错误说：线程“ AWT-EventQueue-0”中的异常java.lang.ClassCastException：个块。皇后不能转换成多个块。国王 在Chess.Board.endangersKing（Board.java:474） 在Chess.Board.mouseClicked（Board.java:348）
如果我使所有子画面都当棋子或切换国王和王后的位置，则可以修复该错误。我想避免这样做，以使其与实际游戏尽可能相似。
对于格式错误，我们深表歉意。这是我第一次使用stackoverflow，因为老师告诉我在问他之前先进行查找。
公共类委员会扩展了JFrame实现的MouseListener { / ** *存储板的当前状态 * / 私人ChessSquare [] [] boardState;
/**
* White Rook 1
*/
private Castle wr01;
/**
* White Rook 2
*/
private Castle wr02;
/**
* Black Rook 1
*/
private Castle br01;
/**
* Black Rook 2
*/
private Castle br02;
/**
* White Knight 1
*/
private Horse wk01;
/**
* White Knight 2
*/
private Horse wk02;
/**
* Black Knight 1
*/
private Horse bk01;
/**
* Black Knight 2
*/
private Horse bk02;
/**
* White Bishop 1
*/
private Bishop wb01;
/**
* White Bishop 2
*/
private Bishop wb02;
/**
* Black Bishop 1
*/
private Bishop bb01;
/**
* Black Bishop 2
*/
private Bishop bb02;
/**
* White Queen
*/
private Queen wq;
/**
* Black Queen
*/
private Queen bq;
/**
* White King
*/
private King wk;
/**
* Black King
*/
private King bk;
/**
* White Pawns
*/
private Pawn wp[] = new Pawn[8];
/**
* Black Pawns
*/
private Pawn bp[] = new Pawn[8];
/**
* Indicates it is white's turn
*/
private static final String WHITE_MOVE = "WHITE";
/**
* Indicates it is black's turn
*/
private static final String BLACK_MOVE = "BLACK";
/**
* Stores the current turn as a string
*/
static String move = WHITE_MOVE;
/**
* White player object
*/
private Player whitePlayer = null;
/**
* Black player object
*/
private Player blackPlayer = null;
/**
* graphic container for board
*/
private JPanel board;
/**
* graphic container for option menu
*/
private JPanel optionPanel;
/**
* temporary square used in initialization
*/
private ChessSquare cs;
/**
* temporary square used in game
*/
private ChessSquare c;
/**
* placeholder for first cell clicked - piece must not be null
*/
private ChessSquare previous;
/**
* Stores players turn as int
*/
private int chance;
/**
* list of possible destinations of selected piece
*/
private ArrayList<ChessSquare> destinList;
/**
* true if game has ended
*/
private boolean end;
/**
* used to indicate winning player
*/
private Player winner;
/**
* window for win message
*/
private static JFrame winFrame;
/**
* container for win message components
*/
private static JPanel winPanel;
/**
* win message
*/
private static JTextField winText;
/**
* button restarts the game
*/
private static JButton restartButton;
/**
* button exits the application
*/
private static JButton quitButton;
/**
* menu for restarting the application
*/
private static Menu m;
/**
* initializes board and pieces
* @param whitePlayer selected white player to play game
* @param blackPlayer selected black player to play game
*/
public Board(Player whitePlayer, Player blackPlayer) {
if(whitePlayer == null) whitePlayer = new Player("GuestWhitePlayer");
if(blackPlayer == null) blackPlayer = new Player("GuestBlackPlayer");
chance = Piece.COLOR_WHITE;
end = false;//true if game has ended
destinList = new ArrayList<>();
wr01 = new Castle("WR01", "whiteRook.png", Piece.COLOR_WHITE);
wr02 = new Castle("WR02", "whiteRook.png", Piece.COLOR_WHITE);
br01 = new Castle("BR01", "blackRook.png", Piece.COLOR_BLACK);
br02 = new Castle("BR02", "blackRook.png", Piece.COLOR_BLACK);
wk01 = new Horse("WK01", "whiteKnight.png", Piece.COLOR_WHITE);
wk02 = new Horse("WK02", "whiteKnight.png", Piece.COLOR_WHITE);
bk01 = new Horse("BK01", "blackKnight.png", Piece.COLOR_BLACK);
bk02 = new Horse("BK02", "blackKnight.png", Piece.COLOR_BLACK);
wb01 = new Bishop("WB01", "whiteBishop.png", Piece.COLOR_WHITE);
wb02 = new Bishop("WB02", "whiteBishop.png", Piece.COLOR_WHITE);
bb01 = new Bishop("BB01", "blackBishop.png", Piece.COLOR_BLACK);
bb02 = new Bishop("BB02", "blackBishop.png", Piece.COLOR_BLACK);
wq = new Queen("WQ", "whiteQueen.png", Piece.COLOR_WHITE);
bq = new Queen("BQ", "blackQueen.png", Piece.COLOR_BLACK);
wk = new King("WK", "whiteKing.png", Piece.COLOR_WHITE, 7, 3);
bk = new King("BK", "blackKing.png", Piece.COLOR_BLACK, 0, 3);
for(int i = 0 ; i < 8 ; i++) {
wp[i] = new Pawn(("WP0" + (i + 1)), "whitePawn.png", Piece.COLOR_WHITE);
bp[i] = new Pawn(("BP0" + (i + 1)), "blackPawn.png", Piece.COLOR_BLACK);
}
board = new JPanel(new GridLayout(8, 8));
optionPanel = new JPanel();
boardState = new ChessSquare[8][8];
this.whitePlayer = whitePlayer;
this.blackPlayer = blackPlayer;
Piece P;
for(int i = 0 ; i < 8 ; i++) {
for(int j = 0 ; j < 8 ; j++) {
P = null;
if(i == 0 && j == 0) P = br01;
else if(i == 0 && j == 7) P = br02;
else if(i == 7 && j == 0) P = wr01;
else if(i == 7 && j == 7) P = wr02;
else if(i == 0 && j == 1) P = bk01;
else if(i == 0 && j == 6) P = bk02;
else if(i == 7 && j == 1) P = wk01;
else if(i == 7 && j == 6) P = wk02;
else if(i == 0 && j == 2) P = bb01;
else if(i == 0 && j == 5) P = bb02;
else if(i == 7 && j == 2) P = wb01;
else if(i == 7 && j == 5) P = wb02;
else if(i == 0 && j == 3) P = bq;
else if(i == 0 && j == 4) P = bk;
else if(i == 7 && j == 3) P = wq;
else if(i == 7 && j == 4) P = wk;
else if(i == 1) P = bp[j];
else if(i == 6) P = wp[j];
cs = new ChessSquare(i, j, P);
cs.addMouseListener(this);
board.add(cs);
boardState[i][j] = cs;
}
}
setTitle("Chess");
setSize(1200, 825);
setResizable(false);
add(board);
board.setBounds(0, 0, 800, 800);
add(optionPanel);
optionPanel.setBounds(800, 0, 400, 825);
}
/**
* reveals the game board and allows the game to be played
*/
public void play() {
setVisible(true);
//System.out.println("Piece at 0, 0 is ... " + boardState[0][0].getPiece().getPath());//just for testing
}
/**
* retrieves the king of the designated color
* @param color color of the king to be returned
* @return the king of {@code color}
*/
public King getKing(int color) {
if (color == Piece.COLOR_WHITE) return wk;
return bk;
}
@Override
public void mouseClicked(MouseEvent e) {
c = (ChessSquare) e.getSource();
if (previous == null) {//if this is the first piece we are selecting . . .
if(c.getPiece() != null) {
if(c.getPiece().getColor() != chance) return;
c.select();
previous = c;
destinList.clear();
destinList = c.getPiece().move(boardState, c.x, c.y);
if(c.getPiece() instanceof King) destinList = destinaionFilter(destinList, c);
else {
if(boardState[getKing(chance).getX()][getKing(chance).getY()].isCheck()) destinList = new ArrayList<ChessSquare>(destinaionFilter(destinList,c));
else if(destinList.isEmpty() == false && endangersKing(c, destinList.get(0))) destinList.clear();
}
highlightdestinations(destinList);
}
} else {//if we have already selected a piecee and are now selecting a destination
if(c.x == previous.x && c.y == previous.y) {//deselect if the same cell was clicked
c.deselect();
clearDestinations(destinList);
destinList.clear();
previous = null;
} else if(c.getPiece() == null || ( (c.getPiece() != null) && (previous.getPiece().getColor() != c.getPiece().getColor()))) {//null pointer?
if(c.isPossibleDestination()) {
if(c.getPiece() != null) c.removePiece();
c.setPiece(previous.getPiece());
if (previous.isCheck()) previous.removeCheck();
previous.removePiece();
if(getKing(chance^1).threatExists(boardState)) {
boardState[getKing(chance^1).getX()][getKing(chance^1).getY()].setCheck();
if (checkmate(getKing(chance^1).getColor())) {
previous.deselect();
if(previous.getPiece() != null) previous.removePiece();
gameEnd();
}
}
if(getKing(chance).threatExists(boardState) == false) boardState[getKing(chance).getX()][getKing(chance).getY()].removeCheck();
if(c.getPiece() instanceof King) {
((King)c.getPiece()).setX(c.x);
((King)c.getPiece()).setY(c.y);
}
changeChance();
if(!end) {
//restart timer
}
}
if(previous != null) {
previous.deselect();
previous = null;
}
clearDestinations(destinList);
destinList.clear();
} else if(previous.getPiece().getColor() == c.getPiece().getColor()) {
previous.deselect();
clearDestinations(destinList);
destinList.clear();
c.select();
previous = c;
destinList = c.getPiece().move(boardState, c.x, c.y);
if(c.getPiece() instanceof King)
destinList = destinaionFilter(destinList, c);
else {
if(boardState[getKing(chance).getX()][getKing(chance).getY()].isCheck()) destinList = new ArrayList<ChessSquare>(destinaionFilter(destinList,c));
else if(destinList.isEmpty()==false && endangersKing(c,destinList.get(0))) destinList.clear();
}
highlightdestinations(destinList);
}
}
if(c.getPiece() != null && c.getPiece() instanceof King) {
((King)c.getPiece()).setX(c.x);
((King)c.getPiece()).setY(c.y);
}
}
/**
* Alternate turn between players
*/
public void changeChance() {
if (boardState[getKing(chance).getX()][getKing(chance).getY()].isCheck()) {
chance ^= 1;
gameEnd();
}
if(destinList.isEmpty() == false) clearDestinations(destinList);
if(previous != null) previous.deselect();
previous = null;
chance ^= 1;
if(!end /*&& timer != null*/){
//reset timer
if(Board.move == Board.WHITE_MOVE) Board.move = Board.BLACK_MOVE;
else Board.move = Board.WHITE_MOVE;
}
}
/**
* filters out moves that would put the king in danger
* @param destinList list of possible destinations
* @param fromSquare square from which move will be made
* @return new list of destinations with those that harm the king out
*/
private ArrayList<ChessSquare> destinaionFilter (ArrayList<ChessSquare> destinList, ChessSquare fromSquare) {
ArrayList<ChessSquare> newList = new ArrayList<ChessSquare>();
ChessSquare newBoardState[][] = new ChessSquare[8][8];
ListIterator<ChessSquare> it = destinList.listIterator();
int x,y;
while (it.hasNext()) {
for(int i = 0 ; i < 8 ; i++) for(int j = 0 ; j < 8 ; j++) { try { newBoardState[i][j] = new ChessSquare(boardState[i][j]);} catch (CloneNotSupportedException e){e.printStackTrace();}}
ChessSquare temp = it.next();
if(newBoardState[temp.x][temp.y].getPiece() != null) newBoardState[temp.x][temp.y].removePiece();
newBoardState[temp.x][temp.y].setPiece(newBoardState[fromSquare.x][fromSquare.y].getPiece());
x = getKing(chance).getX();
y = getKing(chance).getY();
if(newBoardState[fromSquare.x][fromSquare.y].getPiece() instanceof King) {
((King)(newBoardState[temp.x][temp.y].getPiece())).setX(temp.x);
((King)(newBoardState[temp.x][temp.y].getPiece())).setY(temp.y);
x = temp.x;
y = temp.y;
}
newBoardState[fromSquare.x][fromSquare.y].removePiece();
if ((((King)(newBoardState[x][y].getPiece())).threatExists(newBoardState) == false)) newList.add(temp);
}
return newList;
}
/**
* determines if moving the piece on {@code fromSquare} to {@code toSquare} will harm the king
* @param fromSquare initial square
* @param toSquare square to which the king will be moved
* @return true if the move will put the king in danger, false otherwise
*/
private boolean endangersKing(ChessSquare fromSquare, ChessSquare toSquare) {
ChessSquare[][] newBoardState = new ChessSquare[8][8];
for(int i = 0 ; i < 8 ; i++) for(int j = 0 ; j < 8; j++) { try { newBoardState[i][j] = new ChessSquare(boardState[i][j]);} catch (CloneNotSupportedException e){e.printStackTrace(); System.out.println("Cloning Error"); }}
newBoardState[toSquare.x][toSquare.y].setPiece(newBoardState[fromSquare.x][fromSquare.y].getPiece());
if(newBoardState[toSquare.x][toSquare.y].getPiece() instanceof King) {
((King)(newBoardState[toSquare.x][toSquare.y].getPiece())).setX(toSquare.x);
((King)(newBoardState[toSquare.x][toSquare.y].getPiece())).setY(fromSquare.y);
}
newBoardState[fromSquare.x][fromSquare.y].removePiece();
if (((King)(newBoardState[getKing(chance).getX()][getKing(chance).getY()].getPiece())).threatExists(newBoardState) == true) return true;
else return false;
}
/**
* removes all possible destinations from the list
* @param destinList list to reset destinations of
*/
private void clearDestinations(ArrayList<ChessSquare> destinList) {
ListIterator<ChessSquare> it = destinList.listIterator();
while(it.hasNext()) it.next().setImpossibleDestination();
}
/**
* highlights possible destinations in list
* @param destinList list of possible destinations
*/
private void highlightdestinations(ArrayList<ChessSquare> destinList) {
ListIterator<ChessSquare> it = destinList.listIterator();
while(it.hasNext()) it.next().setPossibleDestination();
}
/**
* filters out destinations that would cause self-check
* @param destinList list of destinations
* @param fromSquare square from which move made
* @param color color of mover
* @return filtered list
*/
private ArrayList<ChessSquare> incheckfilter (ArrayList<ChessSquare> destinList, ChessSquare fromSquare, int color) {
ArrayList<ChessSquare> newList = new ArrayList<>();
ChessSquare[][] newBoardState = new ChessSquare[8][8];
ListIterator<ChessSquare> it = destinList.listIterator();
int x,y;
while (it.hasNext()) {
for(int i=0;i<8;i++) for(int j=0;j<8;j++) { try { newBoardState[i][j] = new ChessSquare(boardState[i][j]);} catch (CloneNotSupportedException e){e.printStackTrace();}}
ChessSquare tempc = it.next();
if(newBoardState[tempc.x][tempc.y].getPiece() != null) newBoardState[tempc.x][tempc.y].removePiece();
newBoardState[tempc.x][tempc.y].setPiece(newBoardState[fromSquare.x][fromSquare.y].getPiece());
x = getKing(color).getX();
y = getKing(color).getY();
if(newBoardState[tempc.x][tempc.y].getPiece() instanceof King) {
((King)(newBoardState[tempc.x][tempc.y].getPiece())).setX(tempc.x);
((King)(newBoardState[tempc.x][tempc.y].getPiece())).setY(tempc.y);
x = tempc.x;
y = tempc.y;
}
newBoardState[fromSquare.x][fromSquare.y].removePiece();
if ((newBoardState[x][y].getPiece() instanceof King) && (((King)(newBoardState[x][y].getPiece())).threatExists(newBoardState) == false)) newList.add(tempc);
}
return newList;
}
/**
* determines if chceckmate has happened
* @param color to check if they are in check
* @return true if {@code color} is in check, false otherwise
*/
public boolean checkmate(int color) {
ArrayList<ChessSquare> dlist = new ArrayList<>();
for(int i=0;i<8;i++) {
for(int j=0;j<8;j++) {
if (boardState[i][j].getPiece() != null && boardState[i][j].getPiece().getColor() == color) {
dlist.clear();
dlist = boardState[i][j].getPiece().move(boardState, i, j);
dlist = incheckfilter(dlist,boardState[i][j],color);
if(dlist.size() != 0) return false;
}
}
}
return true;
}
/**
* run when game is terminated
*/
private void gameEnd() {
String winMsg = "The ";
clearDestinations(destinList);
if(previous != null) previous.removePiece();
if(chance == Piece.COLOR_WHITE) {
//update white player stats, set winner
winner = whitePlayer;
winMsg += "White Player Won!";
whitePlayer.addGamePlayed(true);
blackPlayer.addGamePlayed(false);
} else {
//update black player stats, set winner
winner = blackPlayer;
winMsg += "Black Player Won!";
whitePlayer.addGamePlayed(false);
blackPlayer.addGamePlayed(true);
}
end = true;
//show winner
winMsg += ("\nCongrats " + winner.getUsername());
//dispose this
//System.out.println("SOmeone won");
dispose();
initWinWindow(winMsg);
revealWinWindow();
}
/**
* reveals vistory window
*/
public static void revealWinWindow() { winFrame.setVisible(true); }
/**
* hides victory window
*/
public static void killWinWindow() { winFrame.dispose(); }
/**
* initializes victory window with message {@code msg}
* @param msg message for victory window
*/
private static void initWinWindow(String msg) {
winFrame = new JFrame();
winFrame.setVisible(false);
winPanel = new JPanel();
winPanel.setBackground(Color.black);
winFrame.setTitle("Chess");
winFrame.setBounds(500, 500, 300, 250);
winText = new JTextField();
winText.setText(msg);
winText.setEditable(false);
winText.setBackground(Color.white);
m = new Menu();
restartButton = new JButton("Restart");
restartButton.setBackground(Color.RED);
restartButton.setFont(Menu.f);
quitButton = new JButton("Quit");
quitButton.setBackground(Color.RED);
quitButton.setFont(Menu.f);
winPanel.add(restartButton);
winPanel.add(quitButton);
restartButton.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e) {
winFrame.dispose();
m.start();
}
});
quitButton.addActionListener(new ActionListener(){ public void actionPerformed(ActionEvent e) { System.exit(0); } });
winPanel.add(winText);
winFrame.add(winPanel);
}
@Override
public void mousePressed(MouseEvent e) {}
@Override
public void mouseReleased(MouseEvent e) {}
@Override
public void mouseEntered(MouseEvent e) {}
@Override
public void mouseExited(MouseEvent e) {}
}