如何在java（Android）中编辑.property文件夹

我正在开发一个应用程序，将服务器URL和数据库名称保存在该文件中。我可以使用此方法从该文件成功访问该数据

public static String getConfigValue(Context context, String name, String defaultValue) {
    Resources resources = context.getResources();
    String propValue = defaultValue;

    try {
        InputStream rawResource = resources.openRawResource(R.raw.app);
        Properties properties = new Properties();
        properties.load(rawResource);
        File file = new File(Environment.getExternalStorageDirectory()+"/distribution/properties/app.properties");
        if(file.exists()){
            InputStream inputStream = new FileInputStream(file);
            properties.load(inputStream);
        }
        propValue = properties.getProperty(name);
    } catch (Exception e) {
        Logger log = LoggerFactory.getLogger(PropertiesLoader.class);
        log.error( "Unable to find the config file: ", e);
    }
    return propValue;
}

但是我想添加一个功能来编辑设置中的url，所以我添加了这个方法，但它不起作用

 public static Properties setConfigValue(Context context, String key, String value){
    Resources resources = context.getResources();

    try{
        InputStream rawResource = resources.openRawResource(R.raw.app);
        Properties properties = new Properties();
        properties.load(rawResource);
        File file = new File(Environment.getExternalStorageDirectory()+"/warehouse/properties/app.properties");
        if(file.exists()){
            InputStream inputStream = new FileInputStream(file);
            properties.load(inputStream);
        }
        properties.setProperty(key, value);
        OutputStream output = new FileOutputStream(context.getExternalFilesDir(Environment.DIRECTORY_DOCUMENTS)+ "properties/app.properties");
        properties.store(output, null);

        return properties;

    }catch(Exception e){
        Logger log = LoggerFactory.getLogger(PropertiesLoader.class);
        log.error("Unable to find the config file: ", e);
        return null;
    }

这是保存在

raw

文件夹中的我的

app.properties

文件夹

basicUrl =  url
serverDBName =  dbname