Java连接MySQL数据库

package service;

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

public class FlightQuery2 {
    // 创建静态全局变量
    static Connection conn;

    static Statement st;

    public String flightQuery(String sql) {

        System.out.println("传递过来的url为: " + sql);
        conn = getConnection(); // 同样先要获取连接，即连接到数据库
        String res = "";
        try {
            st = (Statement) conn.createStatement(); // 创建用于执行静态sql语句的Statement对象，st属局部变量

            ResultSet rs = st.executeQuery(sql); // 执行sql查询语句，返回查询数据的结果集

            while (rs.next()) { // 判断是否还有下一个数据

                // 根据字段名获取相应的值
                String airplane_name = rs.getString("airplane_name");
                String plane_number = rs.getString("plane_number");
             
                // 输出查到的记录的各个字段的值
                res = res + airplane_name +"*"+ plane_number + "#";
            }
            conn.close(); // 关闭数据库连接

        } catch (SQLException e) {
            System.out.println("查询数据失败");
        }
        return res;
    }

    /* 获取数据库连接的函数 */
    public Connection getConnection() {
        Connection con = null;
        String dbUrl = "jdbc:mysql://localhost:3306/ticketqueryandschedule";
        String dbUserName = "root";
        String dbPassword = "123456";
        String jdbcName = "com.mysql.jdbc.Driver";

        try {
            Class.forName(jdbcName);
            con = DriverManager.getConnection(dbUrl, dbUserName, dbPassword);

        } catch (Exception e) {
            System.out.println("数据库连接失败" + e.getMessage());
        }
        return con;
    }
    
/*    public static void main(String args[]){
        FlightQuery2 fq = new FlightQuery2();
        System.out.println(fq.flightQuery("select * from flight limit 10"));
    }*/
}