申请数据库资源池的三种方式（Map，properties）

方式一：常规申请和归还

public static void main(String[] args) throws SQLException {

   //创建连接池申请连接对象
    DruidDataSource ds = new DruidDataSource();
    ds.setDriverClassName("com.mysql.jdbc.Driver");
    ds.setUrl("jdbc:mysql://localhost:3306/test");
    ds.setUsername("root");
    ds.setPassword("123456");
    //设置最大连接
    ds.setMaxActive(10);
    //向连接池对象（创建一定数量的连接对象）
    for (int i = 1; i < 9; i++) {
        DruidPooledConnection conn = ds.getConnection();
        System.out.println(conn);
        if (i == 7) {
            conn.close();
        }

    }
}

方式二：通过引用资源文件申请

@Test
public void test02() throws Exception {

    Properties pro = new Properties();
    pro.setProperty("driverClassName","com.mysql.jdbc.Driver");
    pro.setProperty("url","jdbc:mysql://localhost:3306/test");
    pro.setProperty("username","root");
    pro.setProperty("password","123456");
    DataSource source = DruidDataSourceFactory.createDataSource(pro);

    for (int i = 1; i <=8; i++) {
        Connection connection = source.getConnection();
        System.out.println(connection);
    }
}

方式三：通过Map

@Test
public void test01() throws Exception {

    HashMap map = new HashMap<>();
    map.put("driverClassName","com.mysql.jdbc.Driver");
    map.put("url","jdbc:mysql://localhost:3306/test");
    map.put("username","root");
    map.put("password","123456");
    DataSource ds = DruidDataSourceFactory.createDataSource(map);

    for (int i = 1; i < 9; i++) {
        Connection conn = ds.getConnection();
        System.out.println(conn);
        }
    }