JDBC连接数据库的几种方法

 1         @Test
 2     public void testDriver() throws SQLException {
 3         // 1. 创建一个 Driver 实现类的对象
 4         Driver dirver = new com.mysql.jdbc.Driver();
 5 
 6         // 2. 准备链接数据库的基本信息：url, user, password
 7         String url = "jdbc:mysql://127.0.0.1:3306/java_jdbc";
 8         Properties info = new Properties();
 9         info.put("user", "root");
10         info.put("password", "123456");
11 
12         // 3. 调用 Driver 借口的 connect(url, info) 获取数据库连接
13         Connection connection = dirver.connect(url, info);
14         System.out.println(connection);
15     }

 1     public Connection getConnection() throws Exception {
 2         String driverClass = null;
 3         String jdbcUrl = null;
 4         String user = null;
 5         String password = null;
 6 
 7         // 读取类路径下的jdbc.properties 文件
 8         InputStream in = getClass().getClassLoader().getResourceAsStream("jdbc.properties");
 9         Properties properties = new Properties();
10         properties.load(in);
11 
12         driverClass = properties.getProperty("driver");
13         jdbcUrl = properties.getProperty("jdbcUrl");
14         user = properties.getProperty("user");
15         password = properties.getProperty("password");
16 
17         // 通过反射创建 Driver 对象
18         Driver driver = (Driver) Class.forName(driverClass).newInstance();
19 
20         Properties info = new Properties();
21         info.put("user", user);
22         info.put("password", password);
23 
24         // 通过 Driver 的 connect 方法连接数据库.
25         Connection connection = driver.connect(jdbcUrl, info);
26 
27         return connection;
28     }
29 
30     @Test
31     public void testGetConnection() throws Exception {
32         System.out.println(getConnection());
33     }

 1     @Test
 2     public void testGetConnection23() throws Exception {
 3         System.out.println(getConnection2());
 4     }
 5     public Connection getConnection2() throws IOException, ClassNotFoundException, SQLException{
 6         
 7         Properties properties = new Properties();
 8         
 9         InputStream inputStream = this.getClass().getClassLoader().getResourceAsStream("jdbc.properties");
10         
11         properties.load(inputStream);
12         
13         String driver = properties.getProperty("driver");
14         String jdbcUrl = properties.getProperty("jdbcUrl");
15         String user = properties.getProperty("user");
16         String password = properties.getProperty("password");
17         
18         Class.forName(driver);
19         
20         return DriverManager.getConnection(jdbcUrl, user, password);
21     }