public static String unitConversion(float resource) {

        String[] unit = new String[] { "B", "KB", "M", "G", "T" };

        String formResult = "";

        for (int j = 0; j < unit.length; j++) {

            if (resource < 1024) {

                formResult = resource + unit[j];

                break;

            }

            resource = resource / 1024f;

        }

        return formResult;

    }

    public static String convertFileSize(long size) {

        long kb = 1024;

        long mb = kb * 1024;

        long gb = mb * 1024;

        if (size >= gb) {

            return String.format("%.1f GB", (float) size / gb);

        } else if (size >= mb) {

            float f = (float) size / mb;

            return String.format(f > 100 ? "%.0f MB" : "%.1f MB", f);

        } else if (size >= kb) {

            float f = (float) size / kb;

            return String.format(f > 100 ? "%.0f KB" : "%.1f KB", f);

        } else

            return String.format("%d B", size);

    }