判断外置存储卡SD card是否存在并返回路径

/**
 * 通过反射调用获取内置存储和外置sd卡根路径(通用)
 *
 * @param mContext    上下文
 * @param is_removale 是否可移除，false返回内部存储路径，true返回外置SD卡路径
 * @return
 */
private static String getStoragePath(Context mContext, boolean is_removale) {
    String path;
    //使用getSystemService(String)检索一个StorageManager用于访问系统存储功能。
    StorageManager mStorageManager = (StorageManager) mContext.getSystemService(Context.STORAGE_SERVICE);
    Class<?> storageVolumeClazz = null;
    try {
        storageVolumeClazz = Class.forName("android.os.storage.StorageVolume");
        Method getVolumeList = mStorageManager.getClass().getMethod("getVolumeList");
        Method getPath = storageVolumeClazz.getMethod("getPath");
        Method isRemovable = storageVolumeClazz.getMethod("isRemovable");
        Method getState = mStorageManager.getClass().getMethod("getVolumeState", String.class);
        Object result = getVolumeList.invoke(mStorageManager);

        for (int i = 0; i < Array.getLength(result); i++) {
            Object storageVolumeElement = Array.get(result, i);
            path = (String) getPath.invoke(storageVolumeElement);
            String state = (String) getState.invoke(mStorageManager, path);
            boolean removable = (Boolean) isRemovable.invoke(storageVolumeElement);
            File file = new File(path);
            StatFs stat = new StatFs(path);
            String fs = getFileSystem(file);
            if (stat.getTotalBytes() > 1000 * 1000 * 128 && file.canWrite() && is_removale == removable
                    && state.equals(Environment.MEDIA_MOUNTED) && !fs.equals("tmpfs")) {
                return path;
            }
        }
    } catch (Exception e) {
        e.printStackTrace();
    }
    return "";
}

public static String getFileSystem(File path) {
    try {
        Process mount = Runtime.getRuntime().exec("mount");
        BufferedReader reader = new BufferedReader(new InputStreamReader(mount.getInputStream()));
        mount.waitFor();

        String line;
        while ((line = reader.readLine()) != null) {
            String[] split = line.split("\\s+");
            for (int i = 0; i < split.length - 1; i++) {
                if (!split[i].equals("/") && path.getAbsolutePath().startsWith(split[i]))
                    return split[i + 1];
            }
        }
        reader.close();
        mount.destroy();
    } catch (IOException | InterruptedException e) {
        e.printStackTrace();
    }
    return null;
}