以下是用Java开发一个扫雷游戏的基本步骤：

1. 创建一个窗口和画布，用来显示游戏界面。

2. 创建一个游戏逻辑类，包含一些基本的操作，如生成地雷、计算周围地雷数量、打开方格等。

3. 在画布上绘制游戏界面，包括格子、数字、地雷等。

4. 给格子添加鼠标事件，实现左键点击打开方格、右键点击插上旗子等操作。

5. 实现游戏的胜利和失败判定，包括所有非地雷方格都被打开、点中地雷等。

效果如下：

以下是一个简单的代码示例：

import java.awt.*;
import java.awt.event.*;
import java.util.Random;
import javax.swing.*;

public class MineSweeper extends JPanel {
    private int[][] grid;
    private boolean[][] reveal;
    private int numMines;
    private int gridSize;
    private final int BLOCK_SIZE = 30;
    private final int MARGIN = 20;

    public MineSweeper(int gridSize, int numMines) {
        this.gridSize = gridSize;
        this.numMines = numMines;
        grid = new int[gridSize][gridSize];
        reveal = new boolean[gridSize][gridSize];
        setPreferredSize(new Dimension(gridSize * BLOCK_SIZE + MARGIN * 2, gridSize * BLOCK_SIZE + MARGIN * 2));
        addMouseListener(new MouseAdapter() {
            @Override
            public void mouseClicked(MouseEvent e) {
                handleClick(e.getX(), e.getY(), e.getButton());
            }
        });
        generateGrid();
    }

    private void generateGrid() {
        Random rnd = new Random();
        int count = 0;
        while (count < numMines) {
            int x = rnd.nextInt(gridSize);
            int y = rnd.nextInt(gridSize);
            if (grid[x][y] != -1) {
                grid[x][y] = -1;
                count++;
            }
        }
        for (int i = 0; i < gridSize; i++) {
            for (int j = 0; j < gridSize; j++) {
                if (grid[i][j] != -1) {
                    int countMines = 0;
                    for (int x = Math.max(i - 1, 0); x <= Math.min(i + 1, gridSize - 1); x++) {
                        for (int y = Math.max(j - 1, 0); y <= Math.min(j + 1, gridSize - 1); y++) {
                            if (grid[x][y] == -1) {
                                countMines++;
                            }
                        }
                    }
                    grid[i][j] = countMines;
                }
            }
        }
    }

    private void handleClick(int x, int y, int button) {
        if (x < MARGIN || x >= MARGIN + gridSize * BLOCK_SIZE || y < MARGIN || y >= MARGIN + gridSize * BLOCK_SIZE) {
            return;
        }
        int i = (x - MARGIN) / BLOCK_SIZE;
        int j = (y - MARGIN) / BLOCK_SIZE;
        if (button == MouseEvent.BUTTON1) {
            if (reveal[i][j]) {
                return;
            }
            reveal[i][j] = true;
            if (grid[i][j] == -1) {
                JOptionPane.showMessageDialog(this, "You click a mine! Try again!");
                generateGrid();
            } else if (grid[i][j] == 0) {
                for (int x1 = Math.max(i - 1, 0); x1 <= Math.min(i + 1, gridSize - 1); x1++) {
                    for (int y1 = Math.max(j - 1, 0); y1 <= Math.min(j + 1, gridSize - 1); y1++) {
                        if (!reveal[x1][y1]) {
                            handleClick(MARGIN + x1 * BLOCK_SIZE + BLOCK_SIZE / 2, MARGIN + y1 * BLOCK_SIZE + BLOCK_SIZE / 2, MouseEvent.BUTTON1);
                        }
                    }
                }
            }
        } else if (button == MouseEvent.BUTTON3) {
            reveal[i][j] = !reveal[i][j];
        }
        repaint();
    }

    @Override
    public void paintComponent(Graphics g) {
        super.paintComponent(g);
        g.setColor(Color.BLACK);
        g.fillRect(MARGIN, MARGIN, gridSize * BLOCK_SIZE, gridSize * BLOCK_SIZE);
        for (int i = 0; i < gridSize; i++) {
            for (int j = 0; j < gridSize; j++) {
                if (reveal[i][j]) {
                    g.setColor(Color.WHITE);
                    g.fillRect(MARGIN + i * BLOCK_SIZE, MARGIN + j * BLOCK_SIZE, BLOCK_SIZE, BLOCK_SIZE);
                    if (grid[i][j] == -1) {
                        g.setColor(Color.RED);
                        g.fillRect(MARGIN + i * BLOCK_SIZE, MARGIN + j * BLOCK_SIZE, BLOCK_SIZE, BLOCK_SIZE);
                    } else if (grid[i][j] > 0) {
                        g.setColor(Color.BLUE);
                        g.setFont(new Font("Arial", Font.BOLD, BLOCK_SIZE / 2));
                        g.drawString("" + grid[i][j], MARGIN + i * BLOCK_SIZE + BLOCK_SIZE / 4, MARGIN + j * BLOCK_SIZE + BLOCK_SIZE / 2);
                    }
                } else {
                    g.setColor(Color.GRAY);
                    g.fillRect(MARGIN + i * BLOCK_SIZE, MARGIN + j * BLOCK_SIZE, BLOCK_SIZE, BLOCK_SIZE);
                    if (reveal[i][j]) {
                        g.setColor(Color.WHITE);
                        g.fillRect(MARGIN + i * BLOCK_SIZE, MARGIN + j * BLOCK_SIZE, BLOCK_SIZE, BLOCK_SIZE);
                    } else {
                        g.setColor(Color.BLACK);
                        g.drawRect(MARGIN + i * BLOCK_SIZE, MARGIN + j * BLOCK_SIZE, BLOCK_SIZE, BLOCK_SIZE);
                    }
                }
            }
        }
    }

    public static void main(String[] args) {
        JFrame frame = new JFrame("Mine Sweeper");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setResizable(false);
        frame.add(new MineSweeper(10, 10));
        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }
}