CMP 168 Minesweeper

In the game of Minesweeper, a player searches for hidden bombs on a rectangular grid. The game board is represented by a grid of booleans marking bomb locations. A grid value is true if there is a bomb at that location, false otherwise. A user can click on any cell they choose. The game is lost when the user clicks on a cell containing a bomb. The game is won when all cells not containing bombs have been opened and the only remaining cells are those containing bombs.

Given such a grid of bomb locations, the method createCountGrid() constructs a new grid of integers storing the count of bombs in each neighborhood. The neighborhood for a location includes the location itself and its eight adjacent locations. In the returned grid, each value will be a number from 0 to 9.

If passed the boolean grid on the left, createCountGrid() returns the grid of int values on the right:

Here are the example grids: see image.

The examples below demonstrate how to compute the countGrid from the bombGrid.

A. In "Example A" one can see the cell [0][0] has a count of 1 because the only adjacent cell containing a bomb is [1][1].

B. In "Example B" one can see the cell [1][2] has a count of 0 because there are no adjacent cells containing a bomb.

C. In "Example C" one can see the cell [1][1] has a count of 4 because there are 4 adjacent cells containing a bomb. [0][0] , [0][2], [2][0], [2][1]

D. In "Example D" one can see the cell [1][1] has a count of 3 because there are 3 adjacent cells containing a bomb (including the cell itself). [1][1] , [2][0], [2][2]

Examples: see image.

OBJECTIVES

1. Implement the Grid class shown below in the UML, so it can be tested via zyBook

• Implement the private methods createBombGrid() and createCountGrid() as follows:
  • createBombGrid() Creates the boolean 10 x 10 bombGrid shown on the left and randomly places 25 bombs in the grid.
  • createCountGrid() Creates the int 10 x 10 countGrid shown on the right based on the bomb placement in the bombGrid.
• Implement the default constructor so that it initializes the variables and calls the 2 private methods createBombGrid() and createCountGrid()
• Implement the getNumRows() , getNumColumns() , getNumBombs()
• Implement getBombGrid(), which returns a copy of the 2 dimensional boolean array.
• Implement getCountGrid(), which returns a copy of the 2 dimensional int array.
• Implement isBombAtLocation(int row, int column) so that it returns true if a bomb is in the cell, false otherwise.
• Implement getCountAtLocation(int row, int column) so that it returns the sum of the surrounding adjacent bombs counted by retrieving it from the countGrid.

2. Create a GUI using the java Swing package so that it behaves as follows.

• Display the grid, matching the dimensions as specified in the Grid class, hiding the content of all the cells.
• Each cell in the GUI's grid should be a JButton with its own ActionListener.
• When a cell (aka JButton) is clicked there should be one of the following actions triggered.
  • If there is a bomb the game is over and the entire content of the grid is revealed to the player so that cells containing bombs display a bomb, and cells without bombs show their count.
  • If there is no bomb in the cell, the cell's count is revealed from the countGrid to display the number surrounding adjacent bombs.
  • If the cell is the last one without a bomb to be revealed, the game has been won.
• When the game is over the user should be informed via JOptionPane whether they won or lost and be offered the option to play again.
  • If the user chooses "Yes" to play again, a new instance of the Grid should be created and displayed to play again from step 2a.
  • If the user chooses "No" to not play again, all windows are closed and the application exits.

Extra Credit:

1. Implement the overloaded constructors for the Grid class shown below in the UML

• Implement Grid(int rows, int columns), so that it initializes the variables using the passed in values, and calls the 2 private methods createBombGrid() and createCountGrid(). The number of bombs should be 25.
• Implement Grid(int rows, int columns, int numBombs), so that it initializes the variables using the passed in values, and calls the 2 private methods createBombGrid() and createCountGrid(). The number of bombs should be equal to the value passed in.

2. When a user clicks on a cell that has a 0 count reveal adjacent cells as follows:

• All adjacent and connected 0 cells are revealed
• All (non-bomb) cells immediately adjacent to the revealed 0 cells are also revealed.