how to make it another player 27s turn java

1      void doClickSquare(int row, int col) {
2             // This is called by mousePressed() when a player clicks 
3             // on the square in the specified row and col.  It has already 
4             // been checked that a game is, in fact, in progress.
5             
6          /* Check that the user clicked an empty square.  If not, show an
7             error message and exit. */
8             
9          if ( board[row][col] != EMPTY ) {
10             if (currentPlayer == BLACK)
11                message.setText("BLACK:  Please click an empty square.");
12             else
13                message.setText("WHITE:  Please click an empty square.");
14             return;
15          }
16          
17          /* Make the move.  Check if the board is full or if the move
18             is a winning move.  If so, the game ends.  If not, then it's
19             the other user's turn. */
20             
21          board[row][col] = currentPlayer;  // Make the move.
22          Graphics g = getGraphics();
23          drawPiece(g, currentPlayer, row, col);  // Draw the new piece.
24          g.dispose();
25          
26          if (winner(row,col)) {  // First, check for a winner.
27             if (currentPlayer == WHITE)
28                gameOver("WHITE wins the game!");
29             else
30                gameOver("BLACK wins the game!");
31             return;
32          }
33          
34          boolean emptySpace = false;     // Check if the board is full.
35          for (int i = 0; i < 13; i++)
36             for (int j = 0; j < 13; j++)
37                if (board[i][j] == EMPTY)
38                   emptySpace = true;  // The board contains an empty space.
39          if (emptySpace == false) {
40             gameOver("The game ends in a draw.");
41             return;
42          }
43          
44          /* Continue the game.  It's the other player's turn. */
45          
46          if (currentPlayer == BLACK) {
47             currentPlayer = WHITE;
48             message.setText("WHITE:  Make your move.");
49          }
50          else {  
51             currentPlayer = BLACK;
52             message.setText("BLACK:  Make your move.");
53          }
54    
55       }  // end doClickSquare()
56
57

1      int ct = 1;  // Number of pieces in a row belonging to the player.
2      
3      int r, c;    // A row and column to be examined
4      
5      r = row + dirX;  // Look at square in specified direction.
6      c = col + dirY;
7      while ( r >= 0 && r < 13 && c >= 0 && c < 13 
8                                        && board[r][c] == player ) {
9              // Square is on the board, and it 
10              // contains one of the players's pieces.
11         ct++;
12         r += dirX;  // Go on to next square in this direction.
13         c += dirY;
14      }
15
16      r = row - dirX;  // Now, look in the opposite direction.
17      c = col - dirY;
18      while ( r >= 0 && r < 13 && c >= 0 && c < 13 
19                                       && board[r][c] == player ) {
20         ct++;
21         r -= dirX;   // Go on to next square in this direction.
22         c -= dirY;
23      }
24
25

1       public void paint(Graphics g) {
2          
3          /* Draw grid lines in darkGray.  */
4          
5          g.setColor(Color.darkGray);
6          for (int i = 1; i < 13; i++) {
7             g.drawLine(1 + 13*i, 0, 1 + 13*i, getSize().height);
8             g.drawLine(0, 1 + 13*i, getSize().width, 1 + 13*i);
9          }
10          
11          /* Draw a two-pixel black border around the edges of the board. */
12  
13          g.setColor(Color.black);
14          g.drawRect(0,0,getSize().width-1,getSize().height-1);
15          g.drawRect(1,1,getSize().width-3,getSize().height-3);
16          
17          /* Draw the pieces that are on the board. */
18          
19          for (int row = 0; row < 13; row++)
20             for (int col = 0; col < 13; col++)
21                if (board[row][col] != EMPTY)
22                   drawPiece(g, board[row][col], row, col);
23                   
24        }  // end paint()
25

1       private boolean winner(int row, int col) {
2            // This is called just after a piece has been played on the
3            // square in the specified row and column.  It determines
4            // whether that was a winning move by counting the number
5            // of squares in a line in each of the four possible
6            // directions from (row,col).  If there are 5 squares (or more)
7            // in a row in any direction, then the game is won.
8            
9          if (count( board[row][col], row, col, 1, 0 ) >= 5)
10             return true;
11          if (count( board[row][col], row, col, 0, 1 ) >= 5)
12             return true;
13          if (count( board[row][col], row, col, 1, -1 ) >= 5)
14             return true;
15          if (count( board[row][col], row, col, 1, 1 ) >= 5)
16             return true;
17             
18          /* When we get to this point, we know that the game is not won. */
19
20          return false;
21          
22       }  // end winner()
23

1            g.fillOval(3 + 13*col, 3 + 13*row, 10, 10);
2

1       private void drawPiece(Graphics g, int piece, int row, int col) {
2              // Draw a piece in the square at (row,col).  The color 
3              // is specified by the "piece" parameter, which should be 
4              // either BLACK or WHITE.
5          if (piece == WHITE)
6             g.setColor(Color.white);
7          else
8             g.setColor(Color.black);
9          g.fillOval(3 + 13*col, 3 + 13*row, 10, 10);
10       }
11

1                            dirX    dirY    Why?
2                           ----    ----    --------------------------------
3     horizontal direction    1       0       Only x changes.
4     vertical direction      0       1       Only y changes.
5     first diagonal          1       1       Both x and y change.
6     second diagonal         1      -1       Change in opposing directions.
7