JDBC工具类相关

 1 import java.sql.Connection;
 2 import java.sql.DriverManager;
 3 import java.sql.PreparedStatement;
 4 import java.sql.ResultSet;
 5 import java.sql.SQLException;
 6 
 7 /**
 8  * 提供获取连接和释放资源的方法
 9  * 
10  * @author Administrator
11  *
12  */
13 public class JDBCUtils_V1 {
14     /**
15      * 获取连接
16      * 
17      * @return
18      */
19     public static Connection getConnection() {
20         Connection conn = null;
21         try {
22             Class.forName("com.mysql.jdbc.Driver");
23             conn = DriverManager.getConnection("jdbc:mysql://192.168.1.32:3306/web09", "root", "qweasd");
24         } catch (Exception e) {
25             e.printStackTrace();
26         }
27         return conn;
28     }
29     /**
30      * 释放资源
31      * @param conn
32      * @param pstmt
33      * @param rs
34      */
35     public static void release(Connection conn, PreparedStatement pstmt, ResultSet rs) {
36         if (rs != null) {
37             try {
38                 rs.close();
39             } catch (SQLException e) {
40                 e.printStackTrace();
41             }
42         }
43         if (pstmt != null) {
44             try {
45                 pstmt.close();
46             } catch (SQLException e) {
47                 e.printStackTrace();
48             }
49         }
50         if (conn != null) {
51             try {
52                 conn.close();
53             } catch (SQLException e) {
54                 e.printStackTrace();
55             }
56         }
57     }
58 }

 1 private static String driver;
 2 private static String url;
 3 private static String username;
 4 private static String password;
 5 static {
 6     ResourceBundle rb = ResourceBundle.getBundle("a");
 7     driver = rb.getString(driver);
 8     url = rb.getString(url);
 9     username = rb.getString(username);
10     password = rb.getString(password);
11 }

 1 static {
 2         try {
 3             // 1.通过当前类获取类加载器
 4             ClassLoader cl = JDBCUtils_V3.class.getClassLoader();
 5             // 2.通过类加载器获取输入流
 6             InputStream is = cl.getResourceAsStream("a.properties");
 7             // 3.创建一个properties对象
 8             Properties pp = new Properties();
 9             // 4.加载输入流
10             pp.load(is);
11             // 5.获取相关参数
12             driver = pp.getProperty(driver);
13             url = pp.getProperty(url);
14             username = pp.getProperty(username);
15             password = pp.getProperty(password);
16         } catch (IOException e) {
17             e.printStackTrace();
18         }
19     }