读取properties文件的2种方法

一 , ResourceBundle 用法 与 properties 对比
(1) , ResourceBundle 它只能用于读取 , 不能用于写入
properties 可以读取,可以写入
(2) , ResourceBundle 只能用于读取properties结尾的文件 ResourceBundle.getBundle(“bean”);
properties 可以读取任意结尾的文件, 以流的形式任意读取
in = BeanFactory2.class.getClassLoader().getResourceAsStream(“bean.properties”);
(3), ResourceBundle 只能读取类路径下的properties文件,别的地方不行
com.SH.config.bean(包的方式) 正确 com./H/config/bean (路劲方式)错误的

1, ResourceBundle 用法

public class BeanFactory {

private static ResourceBundle bundle;

static {

// 实列bundle
bundle = ResourceBundle.getBundle(“bean”);

}

public static Object getBean(String beanName){
    Object bean = null;
    try {
       String beanPath =  bundle.getString(beanName);
        bean = (IUserDao) Class.forName(beanPath).newInstance();
        return bean;
    } catch (Exception e) {
        throw new RuntimeException(e);
    }
}

}

2 , properties 用法
public class BeanFactory2 {

private static Properties props;
static {
    InputStream in = null;
    try {
         in =  BeanFactory2.class.getClassLoader().getResourceAsStream("bean.properties");
        props = new Properties();
        props.load(in);
    } catch (IOException e) {
        //
    }finally {
        if (in != null){
            try {
                in.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}

public static Object getBean(String beanName){
    Object bean = null;
    try {
       String beanPath = props.getProperty(beanName);
        bean = (IUserDao) Class.forName(beanPath).newInstance();
        return bean;
    } catch (Exception e) {
        throw new RuntimeException(e);
    }
}

}