数据源的手动写:
纯手动的:
下面的这个是用的java写的,而需要的连接池: c3p0
@Test
public void test1() throws Exception {
//
ComboPooledDataSource dataSource = new ComboPooledDataSource();
dataSource.setDriverClass("com.mysql.cj.jdbc.Driver");
dataSource.setJdbcUrl("jdbc:mysql://localhost:3306/db1?characterEncoding=utf8&useSSL=false&serverTimezone=UTC&rewriteBatchedStatements=true");
// dataSource.setJdbcUrl("jdbc:mysql://localhost:3306/db1&serverTimezone=HongKong");
dataSource.setUser("root");
dataSource.setPassword("522636");
Connection connection = dataSource.getConnection();
System.out.println(connection);
connection.close();
}
下面的这个也是使用的Java书写的--》 使用的连接池是 druid ---》
@Test
public void test2() throws SQLException {
// druid
DruidDataSource dataSource = new DruidDataSource();
dataSource.setDriverClassName("com.mysql.cj.jdbc.Driver");
dataSource.setUrl("jdbc:mysql://localhost:3306/db1?characterEncoding=utf8&useSSL=false&serverTimezone=UTC&rewriteBatchedStatements=true");
dataSource.setUsername("root");
dataSource.setPassword("522636");
DruidPooledConnection connection =dataSource.getConnection();
System.out.println(connection);
connection.close();
}
上面的这些方法:是可以的,但是呢,我们在写程序的时候还是需要低耦合的,所以这个时候,我们就会将里面对于数据库的连接对象的内容写到持久化的集合 properties里面去,后期上传以后,我们更改数据库的时候,只需要更改配置文件jdbc。properties就可以了。就实现了低耦合这样的·一个概念。
下面的就是使用配置文件以后的一种书写方法:
首页就是连接数据的配置文件: jdbc。properties
jdbc.driver=com.mysql.cj.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/db1?characterEncoding=utf8&useSSL=false&serverTimezone=UTC&rewriteBatchedStatements=true
jdbc.username=root
jdbc.password=522636
c3p0 的:
@Test
public void test3() throws Exception {
// du c3p0 de
ResourceBundle rb = ResourceBundle.getBundle("jdbc");
String driver = rb.getString("jdbc.driver");
String url = rb.getString("jdbc.url");
String username = rb.getString("jdbc.username");
String password = rb.getString("jdbc.password");
// chuang jian shu ju yuan dui x
ComboPooledDataSource dataSource = new ComboPooledDataSource();
dataSource.setDriverClass(driver);
dataSource.setJdbcUrl(url);
dataSource.setUser(username);
dataSource.setPassword(password);
Connection connection = dataSource.getConnection();
System.out.println(connection);
connection.close();
}
druid的
@Test
public void test4() throws SQLException {
// druid de shuju lianjiedui
ResourceBundle rb = ResourceBundle.getBundle("jdbc");
String driver= rb.getString("jdbc.driver");
String url= rb.getString("jdbc.url");
String username=rb.getString("jdbc.username");
String password= rb.getString("jdbc.password");
DruidDataSource dataSource = new DruidDataSource();
dataSource.setDriverClassName(driver);
dataSource.setUrl(url);
dataSource.setUsername(username);
dataSource.setPassword(password);
DruidPooledConnection connection = dataSource.getConnection();
System.out.println(connection);
connection.close();
}