多线程之模拟数据库连接

 1 import com.sun.org.apache.xpath.internal.SourceTree;
 2 import jdk.internal.util.xml.impl.Input;
 3 
 4 import java.sql.*;
 5 import java.sql.Connection;
 6 import java.util.ArrayList;
 7 import java.util.List;
 8 import java.util.Scanner;
 9 
10 /**
11  * Created by 123 on 2017/07/02.
12  */
13 public class GetConnection {
14 
15     static Scanner input = new Scanner(System.in);
16     static String url = null;
17     static String pwd = null;
18     static String name = null;
19     static Conn con = new Conn();
20     static PreparedStatement ps = null;
21     static ResultSet rs = null;
22 
23     public static void main(String[] args) throws ClassNotFoundException, SQLException, InterruptedException {
24 
25 
26         while (true) {
27             System.out.println("url:");
28             url = input.next();
29 
30             System.out.println("name");
31             name = input.next();
32 
33             System.out.println("pwd");
34             pwd = input.next();
35 
36             Connection conn = getConnection();
37             System.out.println(conn);
38             Fount();
39             Thread.sleep(1000);
40             //先mian线程，再子线程
41         }
42     }
43 
44     static Connection conn = null;
45 
46     //获取连接
47     public static Connection getConnection() throws SQLException, ClassNotFoundException {
48         try {
49             if (conn == null || conn.isClosed()) {
50                 Class.forName("com.mysql.jdbc.Driver");
51                 conn = DriverManager.getConnection(url, name, pwd);
52             }
53         } catch (ClassNotFoundException e) {
54             e.printStackTrace();
55         } catch (SQLException e) {
56             e.printStackTrace();
57         } finally {
58             return conn;
59         }
60     }
61 
62     public static ResultSet executeQuery(String sql, Object... obj) throws ClassNotFoundException, SQLException {
63         conn = getConnection();
64         ps = conn.prepareStatement(sql);
65         for (int i = 0; i < obj.length; i++) {
66             ps.setObject(i + 1, obj[i]);
67         }
68         return ps.executeQuery();
69     }
70 
71     private static void Fount() throws InterruptedException {
72         Thread t = new Thread(new Runnable() {    //匿名类
73             public void run() {
74                 List list = new ArrayList();
75                 try {
76                     rs = executeQuery("select * from topic");
77                     if (rs != null) {
78                         while (rs.next()) {
79                             String name = rs.getString("tname");
80                             list.add(name);
81                         }
82                     }
83 
84                     for (Object item : list) {
85                         System.out.println(item);
86                     }
87                 } catch (ClassNotFoundException e) {
88                     e.printStackTrace();
89                 } catch (SQLException e) {
90                     e.printStackTrace();
91                 }
92             }
93 
94         });
95         t.start();
96         t.join(1000);
97 
98     }
99 }