JAVA 连接MYSQL数据库操作

String strCon = "jdbc:mysql://122.114.147.148:3306/ddd";  //连接字符串
            String strUser = "数据库用户名";               //
            String strPwd = "口令";                  //"
            System.out.println("正在连接数据库...");                

try {  //监控异常
                  Class.forName("com.mysql.jdbc.Driver");  //加载驱动程序
                  Connection con;
                  //获得连接对象
                  con = DriverManager.getConnection(strCon, strUser, strPwd);
                  System.out.println("成功连接到数据库。");
                  Statement sta = con.createStatement();    //创建语句对象
                  //执行SQL语句

                  String strSql = "select a.车次 ,a.列车类型,a.开车时间,b.到达时间,a.车站,b.车站,CONCAT(truncate((b.运行时间-a.运行时间)/60,0),‘小时‘,mod((b.运行时间-a.运行时间),60),‘分钟‘)  as 运行时间,b.硬座-a.硬座+5 as 硬座 from  (select * from sjc2222 where 车站 like ‘%"+textField_3.getText()+"%‘)a,(select * from sjc2222 where 车站 like ‘%"+textField_4.getText()+"%‘)b where a.车次 = b.车次 and a.站序 < b.站序  order by a.开车时间 asc";

                  ResultSet rs=sta.executeQuery(strSql);

                  while(rs.next()){
                      Vector v = new Vector ();
                      v.add(rs.getString("a.车次"));
                      v.add(rs.getString("a.列车类型"));
                      v.add(rs.getString("a.开车时间"));
                      v.add(rs.getString("b.到达时间"));
                      v.add(rs.getString("a.车站"));
                      v.add(rs.getString("b.车站"));
                      v.add(rs.getString("运行时间"));
                      v.add(rs.getString("硬座"));
                      dtm1.addRow(v);
                      System.out.println(v);
                    }    

                    System.out.println(table_1.getRowCount());
                    if(table_1.getRowCount() == 1){
                        table_1.setVisible(false);
                    }else{
                        table_1.setVisible(true);
                    }

                  rs.close();sta.close(); con.close();  

                } catch (ClassNotFoundException cnfe) { cnfe.printStackTrace(); }
                catch (SQLException sqle) { sqle.printStackTrace(); }