配置文件properties

web程序时，放在        非web程序，放在src下

扩展名为properties；格式为key=value，key一般使用 . 隔开，value不支持中文;

加载方法   其中配置文件名为db.properties

1. 直接加载bundle

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

    
2. 加载文件流

    1     private static String driver ;
    2     private static String url ;
    3     private static String username ;
    4     private static String password ;
    5     static{
    6         try {
    7         //1.通过当前类获取类的加载器
    8         ClassLoader loader = JDBCUtils_V3.class.getClassLoader();
    9         //2.通过加载器方法获得输入流
   10         InputStream is = loader.getResourceAsStream("db.properties");
   11         //3.创建properties对象
   12         Properties properties = new Properties();
   13         //4.加载输入流        
   14         properties.load(is);        
   15         //5.获取配置文件的信息
   16         driver = properties.getProperty("driver");
   17         url = properties.getProperty("url");
   18         username = properties.getProperty("username");
   19         password = properties.getProperty("password");
   20         } catch (IOException e) {
   21             // TODO Auto-generated catch block
   22             e.printStackTrace();
   23         }
   24     }