记账本

下面是我连接数据库的代码：

 

 

import java.sql.Connection;
 2 import java.sql.DriverManager;
 3 import java.sql.ResultSet;
 4 import java.sql.SQLException;
 5 
 6 public class Database {
 7      private static String url = "jdbc:mysql://localhost:3306/tally_book?useUnicode=true&characterEncoding=utf8";
 8      private static String user = "root";
 9      private static String password = "ym123";
10      private static String jdbcName="com.mysql.jdbc.Driver";
11      private Connection con=null;
12      public static Connection getConnection() {
13          Connection con=null;
14             try {
15                 Class.forName(jdbcName);
16                 con=DriverManager.getConnection(url, user, password);
17                 System.out.println("数据库连接成功");
18             } catch (Exception e) {
19                 // TODO Auto-generated catch block
20                 System.out.println("数据库连接失败");
21                 e.printStackTrace();
22             }
23             return con;
24         }
25      
26      public static void close(Connection con) {
27          if(con!=null) {
28              try {
29                  con.close();
30              }catch(SQLException e) {
31                  e.printStackTrace();
32              }
33          }
34      }
35      
36      public static void close(java.sql.Statement st,Connection conn) {
37          if(st!=null) {
38              try {
39                  st.close();
40              }catch(SQLException e) {
41                  e.printStackTrace();
42              }
43          }
44          if(conn!=null) {
45              try {
46                  conn.close();
47              }catch(SQLException e) {
48                  e.printStackTrace();
49              }
50          }
51      }
52      
53      public static void close(ResultSet rs, java.sql.Statement st, Connection conn) {
54             if(rs!=null) {
55                 try {
56                     rs.close();
57                 } catch (SQLException e) {
58                     e.printStackTrace();
59                 }
60             }
61             if(st!=null) {
62                 try {
63                     st.close();
64                 } catch (SQLException e) {
65                     e.printStackTrace();
66                 }
67             }
68             if(conn!=null) {
69                 try {
70                     conn.close();
71                 } catch (SQLException e) {
72                     e.printStackTrace();
73                 }
74             }
75       }
76      
77        public static void main(String[] args) throws SQLException {
78             Connection conn = getConnection();
79         }