读取和更新properties配置文件（支持中文）

    首先把需要操作的properties配置文件修改成UTF-8编码

	// 获取properties文件属性值
	public static String readPropertiesFile(String filePath, String key) throws FileNotFoundException, IOException {
		try {
			Properties props = new Properties();
			props.load(new InputStreamReader(new FileInputStream(filePath), "UTF-8")); 
			String value = props.getProperty(key);
			System.out.println(key + "键的值是：" + value);
			return value;
		} catch (Exception e) {
			e.printStackTrace();
			return null;
		}
	}

	/**
	 * 更新（或插入）一对properties信息(主键及其键值) 如果该主键已经存在，更新该主键的值； 如果该主键不存在，则插件一对键值。
	 * 
	 * @param key
	 *            键名
	 * @param value
	 *            键值
	 */
	public static void writePropertiesFile(String filePath, String key, String value) throws IOException {
		Properties properties = new Properties();
		File file = new File(filePath);
		FileInputStream fis = new FileInputStream(file);
		properties.load(new InputStreamReader(new FileInputStream(file),"UTF-8"));
		// 必须先用map将所有的内容先保存,不然一更新,原来的内容都没了
		Map<String, String> map = new HashMap<String, String>();
		Set<Object> keySet = properties.keySet();
		for (Object object : keySet) {
			String keytmp = (String) object;
			String valuetmp = (String) properties.getProperty(keytmp);
			System.out.println(keytmp + "=" + valuetmp);
			map.put(keytmp, valuetmp);
		}
		map.put(key, value);
		for (java.util.Map.Entry<String, String> entry : map.entrySet()) {
			properties.setProperty(entry.getKey(), entry.getValue());
		}
		FileOutputStream fos = new FileOutputStream(file);
		properties.store(new OutputStreamWriter(fos), "update");
		fos.close();
		fis.close();
	}