public static void loadProps(String propertiesUrl) {
    props = new Properties();
    InputStream in = null;
    try {
        in =new BufferedInputStream(new FileInputStream(propertiesUrl));
        props.load(in);
    } catch (FileNotFoundException e) {
        logger.error("jdbc.properties文件未找到");
    } catch (IOException e) {
        logger.error("出現IOException");
    } finally {
        try {
            if (null != in) {
                in.close();
            }
        } catch (IOException e) {
            logger.error("jdbc.properties文件流關閉出現異常");
        }
    }
    logger.debug("加載properties文件內容完成...........");
    logger.debug("properties文件內容：" + props);
}

public static String getProperty(String key) {
    if (null == props) {
        logger.debug("加載配置文件出錯");
    }
    return props.getProperty(key);
}

java 讀取項目外面配置文件的方法