private static String filterString(final String name) {
		if (name == null) return null;
		StringBuilder buffer = null;
		for (int i = 0; i < name.length(); i ++) {
			final char c = name.charAt(i);
			if (c < 0x20) {		// Bad char found
				if (buffer == null) buffer = new StringBuilder(name.length()).append(name, 0, i);
			} else if (buffer != null) buffer.append(c);
		}
		return buffer == null ? name : buffer.toString();
	}
Get the cached label if valid. If not cached or invalid, trigger an asynchronous update.
mobile/src/main/java/com/oasisfeng/common/app/AppLabelCache.java