@Nullable
	default String getFileExtension() {
		String fileName = getName();
		int i = fileName.indexOf('.') + 1;
		if (i > 0)
			return fileName.toLowerCase().substring(i);
		return null;
	}
@return File extension of {@link #getName() the file name}, if any exists.
recaf-core/src/main/java/software/coley/recaf/info/FileInfo.java