1 public static void main(String[] args) {
 2 Scanner s = new Scanner(System.in);
 3         System.out.println("请输入desc或asc,desc表示降序，asc表示升序");
 4         System.out.print("请输入:");
 5         //读取输入的这一行，并赋值给keyWords
 6         String keyWords = s.nextLine();
 7         //执行SQL，JDBC编程六步
 8         Connection conn = null;
 9         Statement stmt = null;
10         ResultSet rs = null;   //ResultSet是封装了结果集的对象
11        
12         try {
13             //注册驱动
14             Class.forName("com.mysql.jdbc.Driver");
15             //然后获取连接
16             conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/user","root","root"); 
17
18  
19             //获取数据库操作对象
20             stmt = conn.createStatement();
21 
22             //执行SQL
23             String sql="select loginName from t_user order by loginName "+keyWords;
24             rs = stmt.executeQuery(sql);
25 
26             //结果集进行遍历循环
27             while(rs.next()){//如果结果集有数据
28                 System.out.println(rs.getString("loginName"));
29 
30             }
31         } catch (Exception e) {
32             e.printStackTrace();
33         } finally {
34             if (rs != null){
35                 try {
36                     rs.close();
37                 } catch (SQLException e) {
38                     e.printStackTrace();
39                 }
40             }
41 　　　　　　　//资源释放
42             if (conn != null){
43                 try {
44                     conn.close();
45                 } catch (SQLException e) {
46                     e.printStackTrace();
47                 }
48             }
49 
50             if (stmt != null){
51                 try {
52                     stmt.close();
53                 } catch (SQLException e) {
54                     e.printStackTrace();
55                 }
56             }
57         }
58     }

  String sql="select loginName from t_user order by loginName "+keyWords;