用mysql怎么建立数据库连接

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

public class MySQLConnectionExample {
    public static void main(String[] args) {
        String url = "jdbc:mysql://localhost:3306/mydatabase";
        String username = "root";
        String password = "password";
        
        try {
            // 建立连接
            Connection connection = DriverManager.getConnection(url, username, password);
            
            // 执行 SQL 语句
            // ...
            
            // 关闭连接
            connection.close();
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}

import com.zaxxer.hikari.HikariConfig;
import com.zaxxer.hikari.HikariDataSource;

import java.sql.Connection;
import java.sql.SQLException;

public class MySQLConnectionPoolExample {
    public static void main(String[] args) {
        HikariConfig config = new HikariConfig();
        config.setJdbcUrl("jdbc:mysql://localhost:3306/mydatabase");
        config.setUsername("root");
        config.setPassword("password");
        
        HikariDataSource dataSource = new HikariDataSource(config);
        
        try (Connection connection = dataSource.getConnection()) {
            // 执行 SQL 语句
            // ...
        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            dataSource.close();
        }
    }
}