mysql数据库连接javaweb

try {
    Class.forName("com.mysql.cj.jdbc.Driver");
    String url = "jdbc:mysql://localhost:3306/mydatabase";
    String user = "username";
    String password = "password";
    Connection conn = DriverManager.getConnection(url, user, password);
} catch (ClassNotFoundException e) {
    e.printStackTrace();
} catch (SQLException e) {
    e.printStackTrace();
}

HikariConfig config = new HikariConfig();
config.setJdbcUrl("jdbc:mysql://localhost:3306/mydatabase");
config.setUsername("username");
config.setPassword("password");
HikariDataSource ds = new HikariDataSource(config);

try (Connection conn = ds.getConnection()) {
    // 执行数据库操作
} catch (SQLException e) {
    e.printStackTrace();
}

String sql = "SELECT * FROM users WHERE username = ?";
try (Connection conn = ds.getConnection();
     PreparedStatement pstmt = conn.prepareStatement(sql)) {
    pstmt.setString(1, username);
    ResultSet rs = pstmt.executeQuery();
    // 处理结果集
} catch (SQLException e) {
    e.printStackTrace();
}

import java.sql.*;

public class MySQLExample {
    public static void main(String[] args) {
        String url = "jdbc:mysql://localhost:3306/mydatabase";
        String user = "username";
        String password = "password";

        try (Connection conn = DriverManager.getConnection(url, user, password)) {
            String sql = "SELECT * FROM users";
            try (Statement stmt = conn.createStatement();
                 ResultSet rs = stmt.executeQuery(sql)) {
                while (rs.next()) {
                    System.out.println("ID: " + rs.getInt("id") + ", Name: " + rs.getString("name"));
                }
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}